CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Time-to-digital converter - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"41bc380d-3d6f-400c-84e1-be6c1af44964","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Time-to-digital_converter","wgTitle":"Time-to-digital converter","wgCurRevisionId":1214307871,"wgRevisionId":1214307871,"wgArticleId":715886,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Articles needing additional references from November 2012","All articles needing additional references","Articles lacking in-text citations from May 2009","All articles lacking in-text citations","Articles with multiple maintenance issues","All articles with unsourced statements","Articles with unsourced statements from March 2012","Digital circuits","Digital signal processing","Measuring instruments","Radio electronics","Signal processing","Time"], "wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Time-to-digital_converter","wgRelevantArticleId":715886,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":40000,"wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false, "wgWikibaseItemId":"Q2434524","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","ext.math.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","mediawiki.page.media","ext.scribunto.logs","site", "mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.quicksurveys.init","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.math.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Time-to-digital converter - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Time-to-digital_converter"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Time-to-digital_converter&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Time-to-digital_converter"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Time-to-digital_converter rootpage-Time-to-digital_converter skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Time-to-digital+converter" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Time-to-digital+converter" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Time-to-digital+converter" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Time-to-digital+converter" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Application" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Application"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Application</span> </div> </a> <ul id="toc-Application-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Coarse_measurement" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Coarse_measurement"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Coarse measurement</span> </div> </a> <button aria-controls="toc-Coarse_measurement-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Coarse measurement subsection</span> </button> <ul id="toc-Coarse_measurement-sublist" class="vector-toc-list"> <li id="toc-Basic_counter" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Basic_counter"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Basic counter</span> </div> </a> <ul id="toc-Basic_counter-sublist" class="vector-toc-list"> <li id="toc-Counter_technology" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Counter_technology"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.1</span> <span>Counter technology</span> </div> </a> <ul id="toc-Counter_technology-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Measuring_a_time_interval" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Measuring_a_time_interval"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.2</span> <span>Measuring a time interval</span> </div> </a> <ul id="toc-Measuring_a_time_interval-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Statistical_counter" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Statistical_counter"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Statistical counter</span> </div> </a> <ul id="toc-Statistical_counter-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Fine_measurement" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Fine_measurement"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Fine measurement</span> </div> </a> <button aria-controls="toc-Fine_measurement-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Fine measurement subsection</span> </button> <ul id="toc-Fine_measurement-sublist" class="vector-toc-list"> <li id="toc-Ramp_interpolator" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Ramp_interpolator"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Ramp interpolator</span> </div> </a> <ul id="toc-Ramp_interpolator-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Vernier" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Vernier"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Vernier</span> </div> </a> <ul id="toc-Vernier-sublist" class="vector-toc-list"> <li id="toc-Vernier_interpolator" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Vernier_interpolator"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2.1</span> <span>Vernier interpolator</span> </div> </a> <ul id="toc-Vernier_interpolator-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Vernier_method" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Vernier_method"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2.2</span> <span>Vernier method</span> </div> </a> <ul id="toc-Vernier_method-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Digital_Delay-Line_based_TDC" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Digital_Delay-Line_based_TDC"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Digital Delay-Line based TDC</span> </div> </a> <ul id="toc-Digital_Delay-Line_based_TDC-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Hybrid_measurement" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Hybrid_measurement"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Hybrid measurement</span> </div> </a> <ul id="toc-Hybrid_measurement-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-History" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#History"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>History</span> </div> </a> <ul id="toc-History-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Errors" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Errors"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Errors</span> </div> </a> <ul id="toc-Errors-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Configurations" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Configurations"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Configurations</span> </div> </a> <ul id="toc-Configurations-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Delay_generator" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Delay_generator"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Delay generator</span> </div> </a> <ul id="toc-Delay_generator-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Time-to-digital converter</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 4 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-4" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">4 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Convertidor_de_temps_a_digital" title="Convertidor de temps a digital – Catalan" lang="ca" hreflang="ca" data-title="Convertidor de temps a digital" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Time-to-Digital-Converter" title="Time-to-Digital-Converter – German" lang="de" hreflang="de" data-title="Time-to-Digital-Converter" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Time_to_digital_converter" title="Time to digital converter – Italian" lang="it" hreflang="it" data-title="Time to digital converter" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E6%97%B6%E9%97%B4%E6%95%B0%E5%AD%97%E8%BD%AC%E6%8D%A2%E5%99%A8" title="时间数字转换器 – Chinese" lang="zh" hreflang="zh" data-title="时间数字转换器" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q2434524#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Time-to-digital_converter" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Time-to-digital_converter" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Time-to-digital_converter"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Time-to-digital_converter"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Time-to-digital_converter" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Time-to-digital_converter" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&oldid=1214307871" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Time-to-digital_converter&id=1214307871&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FTime-to-digital_converter"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FTime-to-digital_converter"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Time-to-digital_converter&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Time-to-digital_converter&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q2434524" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><style data-mw-deduplicate="TemplateStyles:r1248332772">.mw-parser-output .multiple-issues-text{width:95%;margin:0.2em 0}.mw-parser-output .multiple-issues-text>.mw-collapsible-content{margin-top:0.3em}.mw-parser-output .compact-ambox .ambox{border:none;border-collapse:collapse;background-color:transparent;margin:0 0 0 1.6em!important;padding:0!important;width:auto;display:block}body.mediawiki .mw-parser-output .compact-ambox .ambox.mbox-small-left{font-size:100%;width:auto;margin:0}.mw-parser-output .compact-ambox .ambox .mbox-text{padding:0!important;margin:0!important}.mw-parser-output .compact-ambox .ambox .mbox-text-span{display:list-item;line-height:1.5em;list-style-type:disc}body.skin-minerva .mw-parser-output .multiple-issues-text>.mw-collapsible-toggle,.mw-parser-output .compact-ambox .ambox .mbox-image,.mw-parser-output .compact-ambox .ambox .mbox-imageright,.mw-parser-output .compact-ambox .ambox .mbox-empty-cell,.mw-parser-output .compact-ambox .hide-when-compact{display:none}</style><table class="box-Multiple_issues plainlinks metadata ambox ambox-content ambox-multiple_issues compact-ambox" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/b/b4/Ambox_important.svg/40px-Ambox_important.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/b/b4/Ambox_important.svg/60px-Ambox_important.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/b/b4/Ambox_important.svg/80px-Ambox_important.svg.png 2x" data-file-width="40" data-file-height="40" /></span></span></div></td><td class="mbox-text"><div class="mbox-text-span"><div class="multiple-issues-text mw-collapsible"><b>This article has multiple issues.</b> Please help <b><a href="/wiki/Special:EditPage/Time-to-digital_converter" title="Special:EditPage/Time-to-digital converter">improve it</a></b> or discuss these issues on the <b><a href="/wiki/Talk:Time-to-digital_converter" title="Talk:Time-to-digital converter">talk page</a></b>. <small><i>(<a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove these messages</a>)</i></small> <div class="mw-collapsible-content"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Time-to-digital_converter" title="Special:EditPage/Time-to-digital converter">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Time-to-digital+converter%22">"Time-to-digital converter"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Time-to-digital+converter%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Time-to-digital+converter%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Time-to-digital+converter%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Time-to-digital+converter%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Time-to-digital+converter%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">November 2012</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-More_footnotes_needed plainlinks metadata ambox ambox-style ambox-More_footnotes_needed" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Text_document_with_red_question_mark.svg/40px-Text_document_with_red_question_mark.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Text_document_with_red_question_mark.svg/60px-Text_document_with_red_question_mark.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Text_document_with_red_question_mark.svg/80px-Text_document_with_red_question_mark.svg.png 2x" data-file-width="48" data-file-height="48" /></span></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article includes a list of <a href="/wiki/Wikipedia:Citing_sources#General_references" title="Wikipedia:Citing sources">general references</a>, but <b>it lacks sufficient corresponding <a href="/wiki/Wikipedia:Citing_sources#Inline_citations" title="Wikipedia:Citing sources">inline citations</a></b>.<span class="hide-when-compact"> Please help to <a href="/wiki/Wikipedia:WikiProject_Reliability" title="Wikipedia:WikiProject Reliability">improve</a> this article by <a href="/wiki/Wikipedia:When_to_cite" title="Wikipedia:When to cite">introducing</a> more precise citations.</span> <span class="date-container"><i>(<span class="date">May 2009</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> </div> </div><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>In <a href="/wiki/Electronics" title="Electronics">electronic</a> <a href="/wiki/Instrumentation" title="Instrumentation">instrumentation</a> and <a href="/wiki/Signal_processing" title="Signal processing">signal processing</a>, a <b>time-to-digital converter</b> (<b>TDC</b>) is a device for recognizing events and providing a digital representation of the <a href="/wiki/Time" title="Time">time</a> they occurred. For example, a TDC might output the time of arrival for each incoming pulse. Some applications wish to measure the time interval between two events rather than some notion of an absolute time. </p><p>In <a href="/wiki/Electronics" title="Electronics">electronics</a> <b>time-to-digital converters</b> (TDCs) or <b>time digitizers</b> are devices commonly used to measure a time interval and convert it into digital (binary) output. In some cases <sup id="cite_ref-Kalisz_1-0" class="reference"><a href="#cite_note-Kalisz-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> <a href="#Interpolation">interpolating</a> TDCs are also called <b>time counters</b> (TCs). </p><p>TDCs are used to determine the time interval between two signal pulses (known as start and stop pulse). Measurement is started and stopped when the rising or falling edge of a signal pulse crosses a set threshold. This pattern is seen in many physical experiments, like <a href="/wiki/Time-of-flight" class="mw-redirect" title="Time-of-flight">time-of-flight</a> and lifetime measurements in <a href="/wiki/Atomic_physics" title="Atomic physics">atomic</a> and <a href="/wiki/Particle_physics" title="Particle physics">high energy physics</a>, experiments that involve <a href="/wiki/Laser_rangefinder" title="Laser rangefinder">laser ranging</a> and electronic research involving the testing of <a href="/wiki/Integrated_circuits" class="mw-redirect" title="Integrated circuits">integrated circuits</a> and high-speed data transfer.<sup id="cite_ref-Kalisz_1-1" class="reference"><a href="#cite_note-Kalisz-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Application">Application</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=1" title="Edit section: Application"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>TDCs are used to timestamp events and measure time differences between events, especially where picosecond precision and high accuracy is required, such as the measurement of events in <a href="/wiki/High_energy_physics" class="mw-redirect" title="High energy physics">high energy physics</a> <a href="/wiki/Experiment" title="Experiment">experiments</a>, where particles (e.g. electrons, photons, and ions) are detected. </p><p>Another application is cost-effective and non-mechanical water <a href="/wiki/Time_of_flight#In_flow_meters" title="Time of flight">flow metering</a> by measuring the time difference between ultrasound pulses that travel through the flow and arrive at different times depending on the flow speed and direction.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>In an all-digital <a href="/wiki/Phase-locked_loop" title="Phase-locked loop">phase-locked loop</a> (ADPLL), a TDC measures the phase shift and its result is used to adjust the <a href="/wiki/Numerically_controlled_oscillator" title="Numerically controlled oscillator">digital controlled oscillator</a> (DCO).<sup id="cite_ref-Henzler_2010_Section_6.1_4-0" class="reference"><a href="#cite_note-Henzler_2010_Section_6.1-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Coarse_measurement">Coarse measurement</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=2" title="Edit section: Coarse measurement"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:CMOS_TW_OSC_000.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/00/CMOS_TW_OSC_000.png/220px-CMOS_TW_OSC_000.png" decoding="async" width="220" height="144" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/00/CMOS_TW_OSC_000.png/330px-CMOS_TW_OSC_000.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/00/CMOS_TW_OSC_000.png/440px-CMOS_TW_OSC_000.png 2x" data-file-width="1283" data-file-height="841" /></a><figcaption>A CMOS (rotary) traveling wave <a href="/wiki/Electronic_oscillator" title="Electronic oscillator">oscillator</a> or <a href="/wiki/Digital_delay_line" title="Digital delay line">delay line</a> or <a href="/wiki/Distributed_amplifier" title="Distributed amplifier">distributed amplifier</a> runs at a flip-flop compatible frequency, but has sharper edges and sub-edge resolution</figcaption></figure> <p>If the required time resolution is not high, then counters can be used to make the conversion. </p> <div class="mw-heading mw-heading3"><h3 id="Basic_counter">Basic counter</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=3" title="Edit section: Basic counter"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In its simplest implementation, a TDC is simply a high-<a href="/wiki/Frequency" title="Frequency">frequency</a> <a href="/wiki/Counter_(digital)" title="Counter (digital)">counter</a> that increments every clock cycle. The current contents of the counter represents the current time. When an event occurs, the counter's value is captured in an output register. </p><p>In that approach, the measurement is an integer number of clock cycles, so the measurement is quantized to a clock period. To get finer resolution, a faster clock is needed. The accuracy of the measurement depends upon the stability of the clock frequency. </p><p>Typically a TDC uses a <a href="/wiki/Crystal_oscillator" title="Crystal oscillator">crystal oscillator</a> reference frequency for good long term stability. High stability crystal oscillators are usually relative low frequency such as 10 MHz (or 100 ns resolution).<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> To get better resolution, a <a href="/wiki/Phase-locked_loop" title="Phase-locked loop">phase-locked loop</a> frequency multiplier can be used to generate a faster clock. One might, for example, multiply the crystal reference oscillator by 100 to get a clock rate of 1 GHz (1 ns resolution). </p> <div class="mw-heading mw-heading4"><h4 id="Counter_technology">Counter technology</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=4" title="Edit section: Counter technology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>High clock rates impose additional design constraints on the counter: if the clock period is short, it is difficult to update the count. Binary counters, for example, need a fast carry architecture because they essentially add one to the previous counter value. A solution is using a hybrid counter architecture. A <a href="/wiki/Ring_counter" title="Ring counter">Johnson counter</a>, for example, is a fast non-binary counter. It can be used to count very quickly the low order count; a more conventional binary counter can be used to accumulate the high order count. The fast counter is sometime called a <a href="/wiki/Prescaler" title="Prescaler">prescaler</a>. </p><p>The speed of counters fabricated in <a href="/wiki/CMOS" title="CMOS">CMOS</a>-technology is limited by the capacitance between the gate and the channel and by the resistance of the channel and the signal traces. The product of both is the cut-off-frequency. Modern chip technology allows multiple metal layers and therefore coils with a large number of windings to be inserted into the chip. This allows designers to peak the device for a specific <a href="/wiki/Frequency" title="Frequency">frequency</a>, which may lie above the cut-off-frequency of the original transistor.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (March 2012)">citation needed</span></a></i>]</sup> </p><p>A peaked variant of the Johnson counter is the <a href="/wiki/Distributed_amplifier" title="Distributed amplifier">traveling-wave</a> counter which also achieves sub-cycle resolution. Other methods to achieve sub-cycle resolution include <a href="/wiki/Analog-to-digital_converter" title="Analog-to-digital converter">analog-to-digital converters</a> and <a href="/wiki/Vernier_scale" title="Vernier scale">vernier</a> <a href="/wiki/Counter_(digital)" title="Counter (digital)">Johnson counters</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (March 2012)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading4"><h4 id="Measuring_a_time_interval">Measuring a time interval</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=5" title="Edit section: Measuring a time interval"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:CoarseCounting.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/50/CoarseCounting.png/220px-CoarseCounting.png" decoding="async" width="220" height="145" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/50/CoarseCounting.png/330px-CoarseCounting.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/50/CoarseCounting.png/440px-CoarseCounting.png 2x" data-file-width="1860" data-file-height="1230" /></a><figcaption>sketch of the coarse counting method in TDCs: showing measurements of T in various relations to the clock pulses</figcaption></figure> <p>In most situations, the user does not want to just capture an arbitrary time that an event occurs, but wants to measure a time interval, the time between a start event and a stop event. </p><p>That can be done by measuring an arbitrary time of both the start and stop events and subtracting. The measurement can be off by two counts. </p><p>The subtraction can be avoided if the counter is held at zero until the start event, counts during the interval, and then stops counting after the stop event. </p><p><b>Coarse counters</b> base on a <a href="/wiki/Clock_signal" title="Clock signal">reference clock</a> with signals generated at a stable <a href="/wiki/Frequency" title="Frequency">frequency</a> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle f_{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>f</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle f_{0}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6423b30a4c5770c59b5ab92dcb4ce378755440ab" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.193ex; height:2.509ex;" alt="{\displaystyle f_{0}}"></span>.<sup id="cite_ref-Kalisz_1-2" class="reference"><a href="#cite_note-Kalisz-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> When the start signal is detected the <a href="/wiki/Counter_(digital)" title="Counter (digital)">counter</a> starts counting clock signals and terminates counting after the stop signal is detected. The time interval <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ec7200acd984a1d3a3d7dc455e262fbe54f7f6e0" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.636ex; height:2.176ex;" alt="{\displaystyle T}"></span> between start and stop is then </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T=n\cdot T_{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mo>=</mo> <mi>n</mi> <mo>⋅</mo> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T=n\cdot T_{0}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ebdd795f5c9638dab8403e7572ae55f2dd3a0767" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:10.22ex; height:2.509ex;" alt="{\displaystyle T=n\cdot T_{0}}"></span></dd></dl> <p>with <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>n</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a601995d55609f2d9f5e233e36fbe9ea26011b3b" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.395ex; height:1.676ex;" alt="{\displaystyle n}"></span>, the number of counts and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T_{0}=1/f_{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> <mo>=</mo> <mn>1</mn> <mrow class="MJX-TeXAtom-ORD"> <mo>/</mo> </mrow> <msub> <mi>f</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T_{0}=1/f_{0}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/34037f001b5ccb224dff14867874f16400277666" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:10.029ex; height:2.843ex;" alt="{\displaystyle T_{0}=1/f_{0}}"></span>, the period of the <a href="/wiki/Clock_signal" title="Clock signal">reference clock</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Statistical_counter">Statistical counter</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=6" title="Edit section: Statistical counter"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Since start, stop and <a href="/wiki/Clock_signal" title="Clock signal">clock signal</a> are asynchronous, there is a uniform <a href="/wiki/Probability_distribution" title="Probability distribution">probability distribution</a> of the start and stop signal-times between two subsequent clock pulses. This detuning of the start and stop signal from the clock pulses is called <a href="/wiki/Quantization_error" class="mw-redirect" title="Quantization error">quantization error</a>. </p><p>For a series of measurements on the same constant and asynchronous time interval one measures two different numbers of counted clock pulses <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n_{1}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n_{1}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ee784b70e772f55ede5e6e0bdc929994bff63413" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.449ex; height:2.009ex;" alt="{\displaystyle n_{1}}"></span> and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n_{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n_{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/840e456e3058bc0be28e5cf653b170cdbfcc3be4" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.449ex; height:2.009ex;" alt="{\displaystyle n_{2}}"></span> (see picture). These occur with <a href="/wiki/Probabilities" class="mw-redirect" title="Probabilities">probabilities</a> </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle p(n_{1})=1-c}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>p</mi> <mo stretchy="false">(</mo> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo stretchy="false">)</mo> <mo>=</mo> <mn>1</mn> <mo>−</mo> <mi>c</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle p(n_{1})=1-c}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/19e11d84baff3bafc97cdfb5da96cfe790b0e312" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; margin-left: -0.089ex; width:13.625ex; height:2.843ex;" alt="{\displaystyle p(n_{1})=1-c}"></span></dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle q(n_{2})=c}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>q</mi> <mo stretchy="false">(</mo> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mo stretchy="false">)</mo> <mo>=</mo> <mi>c</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle q(n_{2})=c}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4050440a3d5091a22c529743f51a2e5ceac1da02" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:9.433ex; height:2.843ex;" alt="{\displaystyle q(n_{2})=c}"></span></dd></dl> <p>with <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle c=Frc(T/T_{0})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>c</mi> <mo>=</mo> <mi>F</mi> <mi>r</mi> <mi>c</mi> <mo stretchy="false">(</mo> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mo>/</mo> </mrow> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle c=Frc(T/T_{0})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/373f57527899c8f4cb22c97b054de4d66d60ff71" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:14.921ex; height:2.843ex;" alt="{\displaystyle c=Frc(T/T_{0})}"></span> the <a href="/wiki/Fractional_part" title="Fractional part">fractional part</a> of <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T/T_{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mo>/</mo> </mrow> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T/T_{0}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/77077bd0e8de0f99082cf5a3c60059125101eaab" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:5.211ex; height:2.843ex;" alt="{\displaystyle T/T_{0}}"></span>. The value for the time interval is then obtained by </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T=(p\cdot n_{1}+q\cdot n_{2})\cdot T_{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mo>=</mo> <mo stretchy="false">(</mo> <mi>p</mi> <mo>⋅</mo> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>+</mo> <mi>q</mi> <mo>⋅</mo> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mo stretchy="false">)</mo> <mo>⋅</mo> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T=(p\cdot n_{1}+q\cdot n_{2})\cdot T_{0}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fc75c7e44ca9aef1943f4d4ca85040032bbbe39e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:23.97ex; height:2.843ex;" alt="{\displaystyle T=(p\cdot n_{1}+q\cdot n_{2})\cdot T_{0}}"></span></dd></dl> <p>Measuring a time interval using a coarse counter with the averaging method described above is relatively time consuming because of the many repetitions that are needed to determine the probabilities <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle p}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>p</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle p}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/81eac1e205430d1f40810df36a0edffdc367af36" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; margin-left: -0.089ex; width:1.259ex; height:2.009ex;" alt="{\displaystyle p}"></span> and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle q}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>q</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle q}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/06809d64fa7c817ffc7e323f85997f783dbdf71d" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:1.07ex; height:2.009ex;" alt="{\displaystyle q}"></span>. In comparison to the other methods described later on, a coarse counter has a very limited resolution (1ns in case of a 1 GHz <a href="/wiki/Clock_signal" title="Clock signal">reference clock</a>), but satisfies with its theoretically unlimited measuring range. </p> <div class="mw-heading mw-heading2"><h2 id="Fine_measurement">Fine measurement</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=7" title="Edit section: Fine measurement"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In contrast to the coarse counter in the previous section, fine measurement methods with much better accuracy but far smaller measuring range are presented here.<sup id="cite_ref-Kalisz_1-3" class="reference"><a href="#cite_note-Kalisz-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Analog_signal" title="Analog signal">Analogue</a> methods like time interval stretching or double conversion as well as <a href="/wiki/Digital_data" title="Digital data">digital</a> methods like tapped delay lines and the Vernier method are under examination. Though the <a href="/wiki/Analog_signal" title="Analog signal">analogue</a> methods still obtain better accuracies, <a href="/wiki/Digital_data" title="Digital data">digital</a> time interval measurement is often preferred due to its flexibility in <a href="/wiki/Integrated_circuit" title="Integrated circuit">integrated circuit</a> technology and its robustness against external perturbations like temperature changes. </p><p>The counter implementation's accuracy is limited by the clock frequency. If time is measured by whole counts, then the resolution is limited to the clock period. For example, a 10 MHz clock has a resolution of 100 ns. To get resolution finer than a clock period, there are time interpolation circuits.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> These circuits measure the fraction of a clock period: that is, the time between a clock event and the event being measured. The interpolation circuits often require a significant amount of time to perform their function; consequently, the TDC needs a quiet interval before the next measurement. </p> <div class="mw-heading mw-heading3"><h3 id="Ramp_interpolator">Ramp interpolator</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=8" title="Edit section: Ramp interpolator"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>When counting is not feasible because the clock rate would be too high, analog methods can be used. Analog methods are often used to measure intervals that are between 10 and 200 ns.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> These methods often use a capacitor that is charged during the interval being measured.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Sasaki_9-0" class="reference"><a href="#cite_note-Sasaki-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-HP1_11-0" class="reference"><a href="#cite_note-HP1-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Initially, the capacitor is discharged to zero volts. When the start event occurs, the capacitor is charged with a constant current <i>I</i><sub>1</sub>; the constant current causes the voltage <i>v</i> on the capacitor to increase linearly with time. The rising voltage is called the fast ramp. When the stop event occurs, the charging current is stopped. The voltage on the capacitor <i>v</i> is directly proportional to the time interval <i>T</i> and can be measured with an <a href="/wiki/Analog-to-digital_converter" title="Analog-to-digital converter">analog-to-digital converter</a> (ADC). The resolution of such a system is in the range of 1 to 10 ps.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>Although a separate ADC can be used, the ADC step is often integrated into the interpolator. A second constant current <i>I</i><sub>2</sub> is used to discharge the capacitor at a constant but much slower rate (the slow ramp). The slow ramp might be 1/1000 of the fast ramp. This discharge effectively "stretches" the time interval;<sup id="cite_ref-Esk_p27_13-0" class="reference"><a href="#cite_note-Esk_p27-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> it will take 1000 times as long for the capacitor to discharge to zero volts. The stretched interval can be measured with a counter. The measurement is similar to a <a href="/wiki/Integrating_ADC" title="Integrating ADC">dual-slope analog converter</a>. </p><p>The dual-slope conversion can take a long time: a thousand or so clock ticks in the scheme described above. That limits how often a measurement can be made (dead time). Resolution of 1 ps with a 100 MHz (10 ns) clock requires a stretch ratio of 10,000 and implies a conversion time of 150 μs.<sup id="cite_ref-Esk_p27_13-1" class="reference"><a href="#cite_note-Esk_p27-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> To decrease the conversion time, the interpolator circuit can be used twice in a <b>residual interpolator technique</b>.<sup id="cite_ref-Esk_p27_13-2" class="reference"><a href="#cite_note-Esk_p27-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> The fast ramp is used initially as above to determine the time. The slow ramp is only at 1/100. The slow ramp will cross zero at some time during the clock period. When the ramp crosses zero, the fast ramp is turned on again to measure the crossing time (<i>t</i><sub>residual</sub>). Consequently, the time can be determined to 1 part in 10,000. </p><p>Interpolators are often used with a stable system clock. The start event is asynchronous, but the stop event is a following clock.<sup id="cite_ref-Sasaki_9-1" class="reference"><a href="#cite_note-Sasaki-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-HP1_11-1" class="reference"><a href="#cite_note-HP1-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> For convenience, imagine that the fast ramp rises exactly 1 volt during a 100 ns clock period. Assume the start event occurs at 67.3 ns after a clock pulse; the fast ramp integrator is triggered and starts rising. The asynchronous start event is also routed through a synchronizer that takes at least two clock pulses. By the next clock pulse, the ramp has risen to .327 V. By the second clock pulse, the ramp has risen to 1.327 V and the synchronizer reports the start event has been seen. The fast ramp is stopped and the slow ramp starts. The synchronizer output can be used to capture system time from a counter. After 1327 clocks, the slow ramp returns to its starting point, and interpolator knows that the event occurred 132.7 ns before the synchronizer reported. </p><p>The interpolator is actually more involved because there are synchronizer issues and current switching is not instantaneous.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> Also, the interpolator must calibrate the height of the ramp to a clock period.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Vernier">Vernier</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=9" title="Edit section: Vernier"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Vernier_interpolator">Vernier interpolator</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=10" title="Edit section: Vernier interpolator"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The vernier method is more involved.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> The method involves a triggerable oscillator<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> and a coincidence circuit. At the event, the integer clock count is stored and the oscillator is started. The triggered oscillator has a slightly different frequency than the clock oscillator. For sake of argument, say the triggered oscillator has a period that is 1 ns faster than the clock. If the event happened 67 ns after the last clock, then the triggered oscillator transition will slide by −1 ns after each subsequent clock pulse. The triggered oscillator will be at 66 ns after the next clock, at 65 ns after the second clock, and so forth. A coincidence detector looks for when the triggered oscillator and the clock transition at the same time, and that indicates the fraction time that needs to be added. </p><p>The interpolator design is more involved. The triggerable clock must be calibrated to clock. It must also start quickly and cleanly. </p> <div class="mw-heading mw-heading4"><h4 id="Vernier_method">Vernier method</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=11" title="Edit section: Vernier method"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>Vernier method</b> is a <a href="/wiki/Digital_data" title="Digital data">digital</a> version of the time stretching method. Two only slightly detuned <a href="/wiki/Oscillation" title="Oscillation">oscillators</a> (with <a href="/wiki/Frequencies" class="mw-redirect" title="Frequencies">frequencies</a> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle f_{1}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>f</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle f_{1}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/50dfd257a51e037112c917f8a9e47c9c053466df" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.193ex; height:2.509ex;" alt="{\displaystyle f_{1}}"></span> and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle f_{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>f</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle f_{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/cc886fdaa7adc9be11ff4a5076da5e0943bcff58" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.193ex; height:2.509ex;" alt="{\displaystyle f_{2}}"></span>) start their signals with the arrival of the start and the stop signal. As soon as the leading edges of the <a href="/wiki/Oscillation" title="Oscillation">oscillator</a> signals coincide the measurement ends and the number of periods of the oscillators (<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n_{1}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n_{1}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ee784b70e772f55ede5e6e0bdc929994bff63413" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.449ex; height:2.009ex;" alt="{\displaystyle n_{1}}"></span> and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n_{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n_{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/840e456e3058bc0be28e5cf653b170cdbfcc3be4" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.449ex; height:2.009ex;" alt="{\displaystyle n_{2}}"></span> respectively) lead to the original time interval <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ec7200acd984a1d3a3d7dc455e262fbe54f7f6e0" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.636ex; height:2.176ex;" alt="{\displaystyle T}"></span>: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T={\frac {n_{1}-1}{f_{1}}}-{\frac {n_{2}-1}{f_{2}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>−</mo> <mn>1</mn> </mrow> <msub> <mi>f</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mfrac> </mrow> <mo>−</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mo>−</mo> <mn>1</mn> </mrow> <msub> <mi>f</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T={\frac {n_{1}-1}{f_{1}}}-{\frac {n_{2}-1}{f_{2}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/95553159a3fe9673f6a67f70b6a9fe1d2ce5d54a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:22.151ex; height:5.676ex;" alt="{\displaystyle T={\frac {n_{1}-1}{f_{1}}}-{\frac {n_{2}-1}{f_{2}}}}"></span></dd></dl> <p>Since highly reliable <a href="/wiki/Oscillation" title="Oscillation">oscillators</a> with stable and accurate <a href="/wiki/Frequency" title="Frequency">frequency</a> are still quite a challenge one also realizes the vernier method via two tapped delay lines using two slightly different cell delay times <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>τ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/38a7dcde9730ef0853809fefc18d88771f95206c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.202ex; height:1.676ex;" alt="{\displaystyle \tau }"></span>. This setting is called <b>differential delay line</b> or <b>vernier delay line</b>.<sup id="cite_ref-Henzler_2010_Section_5.3_18-0" class="reference"><a href="#cite_note-Henzler_2010_Section_5.3-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p><p>In the example presented here the first delay line affiliated with the start signal contains cells of <a href="/wiki/Flip-flop_(electronics)#D_flip-flop" title="Flip-flop (electronics)">D-flip-flops</a> with delay <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau _{L}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>τ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>L</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau _{L}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6de509a7f4ac0072b8ad21c259eab796974a0cc7" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.368ex; height:2.009ex;" alt="{\displaystyle \tau _{L}}"></span> which are initially set to transparent. During the transition of the start signal through one of those cells, the signal is delayed by <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau _{L}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>τ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>L</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau _{L}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6de509a7f4ac0072b8ad21c259eab796974a0cc7" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.368ex; height:2.009ex;" alt="{\displaystyle \tau _{L}}"></span> and the state of the flip-flop is sampled as transparent. The second delay line belonging to the stop signal is composed of a series of <a href="/wiki/Operational_amplifier#Applications" title="Operational amplifier">non-inverting buffers</a> with delay <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau _{B}<\tau _{L}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>τ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>B</mi> </mrow> </msub> <mo><</mo> <msub> <mi>τ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>L</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau _{B}<\tau _{L}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4c6e61bc9926d0bd616fb315eb1be0faf0f0a176" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:7.962ex; height:2.176ex;" alt="{\displaystyle \tau _{B}<\tau _{L}}"></span>. Propagating through its channel the stop signal latches the flip-flops of the start signal's delay line. As soon as the stop signal passes the start signal, the latter is stopped and all leftover flip-flops are sampled opaque. Analogous to the above case of the oscillators the wanted time interval <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ec7200acd984a1d3a3d7dc455e262fbe54f7f6e0" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.636ex; height:2.176ex;" alt="{\displaystyle T}"></span> is then </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T=n\cdot (\tau _{1}-\tau _{2})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mo>=</mo> <mi>n</mi> <mo>⋅</mo> <mo stretchy="false">(</mo> <msub> <mi>τ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>−</mo> <msub> <mi>τ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T=n\cdot (\tau _{1}-\tau _{2})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b3257f184e31463af15d882e823c07805cbcd1b8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:16.599ex; height:2.843ex;" alt="{\displaystyle T=n\cdot (\tau _{1}-\tau _{2})}"></span></dd></dl> <p>with n the number of cells marked as transparent. </p> <div class="mw-heading mw-heading3"><h3 id="Digital_Delay-Line_based_TDC">Digital Delay-Line based TDC</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=12" title="Edit section: Digital Delay-Line based TDC"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:TapDelayLine.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3f/TapDelayLine.png/309px-TapDelayLine.png" decoding="async" width="309" height="105" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3f/TapDelayLine.png/464px-TapDelayLine.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3f/TapDelayLine.png/618px-TapDelayLine.png 2x" data-file-width="4860" data-file-height="1650" /></a><figcaption>Tapped delay line using chained <a href="/wiki/D-latch" class="mw-redirect" title="D-latch">D-latches</a> each with delay <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>τ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/38a7dcde9730ef0853809fefc18d88771f95206c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.202ex; height:1.676ex;" alt="{\displaystyle \tau }"></span> and controlled by the stop signal, which freezes all latches so the start signal stops propagating. Then their state can be read by an <a href="/wiki/Encoder_(digital)" title="Encoder (digital)">encoder</a> to determine the delay.</figcaption></figure> <p>In general a <b>digital delay-line based TDC</b>,<sup id="cite_ref-Henzler_2010_Section_2.4_19-0" class="reference"><a href="#cite_note-Henzler_2010_Section_2.4-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> also known as <b>tapped delay line</b>, contains a chain of cells (e.g. using <a href="/wiki/D-latch" class="mw-redirect" title="D-latch">D-latches</a> in the figure) with well defined delay times <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>τ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/38a7dcde9730ef0853809fefc18d88771f95206c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.202ex; height:1.676ex;" alt="{\displaystyle \tau }"></span>. The start signal propagates through this chain and is successively delayed by each cell. The number of cells that the start signal propagated through when the stop signal happens will be the (<a href="/wiki/Rounding" title="Rounding">rounded</a>) time interval between the start and stop signal divided by <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \tau }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>τ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \tau }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/38a7dcde9730ef0853809fefc18d88771f95206c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.202ex; height:1.676ex;" alt="{\displaystyle \tau }"></span>. </p> <div class="mw-heading mw-heading2"><h2 id="Hybrid_measurement">Hybrid measurement</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=13" title="Edit section: Hybrid measurement"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Nutt.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Nutt.png/220px-Nutt.png" decoding="async" width="220" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Nutt.png/330px-Nutt.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Nutt.png/440px-Nutt.png 2x" data-file-width="1920" data-file-height="1050" /></a><figcaption>Sketch of the Nutt interpolation method</figcaption></figure> <p>Counters can measure long intervals but have limited resolution. Interpolators have high resolution but they cannot measure long intervals. A hybrid approach can achieve both long intervals and high resolution.<sup id="cite_ref-Kalisz_1-4" class="reference"><a href="#cite_note-Kalisz-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The long interval can be measured with a counter. The counter information is supplemented with two time interpolators: one interpolator measures the (short) interval between the start event and a following clock event, and the second interpolator measure the interval between the stop event and a following clock event. The basic idea has some complications: the start and stop events are asynchronous, and one or both might happen close to a clock pulse. The counter and interpolators must agree on matching the start and end clock events. To accomplish that goal, synchronizers are used. </p><p>The common hybrid approach is the <b>Nutt method</b>.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> In this example the fine measurement circuit measures the time between start and stop pulse and the respective second nearest clock pulse of the coarse counter (<i>T</i><sub>start</sub>, <i>T</i><sub>stop</sub>), detected by the synchronizer (see figure). Thus the wanted time interval is </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle T=nT_{0}+T_{\mathrm {start} }-T_{\mathrm {stop} }}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>T</mi> <mo>=</mo> <mi>n</mi> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> <mo>+</mo> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">s</mi> <mi mathvariant="normal">t</mi> <mi mathvariant="normal">a</mi> <mi mathvariant="normal">r</mi> <mi mathvariant="normal">t</mi> </mrow> </mrow> </msub> <mo>−</mo> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">s</mi> <mi mathvariant="normal">t</mi> <mi mathvariant="normal">o</mi> <mi mathvariant="normal">p</mi> </mrow> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle T=nT_{0}+T_{\mathrm {start} }-T_{\mathrm {stop} }}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/19e813969b26e1d3970bfba2f86d6d5398b43817" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:23.819ex; height:2.843ex;" alt="{\displaystyle T=nT_{0}+T_{\mathrm {start} }-T_{\mathrm {stop} }}"></span></dd></dl> <p>with <i>n</i> the number of counter clock pulses and <i>T</i><sub>0</sub> the period of the coarse counter. </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=14" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Time measurement has played a crucial role in the understanding of nature from the earliest times. Starting with sun, sand or water driven <a href="/wiki/Clock" title="Clock">clocks</a> we are able to use clocks today, based on the most precise <a href="/wiki/Caesium" title="Caesium">caesium</a> resonators. </p><p>The first direct predecessor of a TDC was invented in the year 1942 by <a href="/wiki/Bruno_Rossi" title="Bruno Rossi">Bruno Rossi</a> for the measurement of <a href="/wiki/Muon" title="Muon">muon</a> lifetimes.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> It was designed as a <b>time-to-amplitude-converter</b>, constantly charging a <a href="/wiki/Capacitor" title="Capacitor">capacitor</a> during the measured time interval. The corresponding <a href="/wiki/Voltage" title="Voltage">voltage</a> is directly proportional to the time interval under examination. </p><p>While the basic concepts (like Vernier methods (<a href="/wiki/Pierre_Vernier" title="Pierre Vernier">Pierre Vernier</a> 1584-1638) and time stretching) of dividing time into measurable intervals are still up-to-date, the implementation changed a lot during the past 50 years. Starting with <a href="/wiki/Vacuum_tubes" class="mw-redirect" title="Vacuum tubes">vacuum tubes</a> and <a href="/wiki/Transformer_types#RF_transformer" title="Transformer types">ferrite pot-core transformers</a> those ideas are implemented in complementary metal–oxide–semiconductor (<a href="/wiki/CMOS" title="CMOS">CMOS</a>) design today.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Errors">Errors</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=15" title="Edit section: Errors"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <dl><dd><small>Some information from <sup id="cite_ref-Kalisz_1-5" class="reference"><a href="#cite_note-Kalisz-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></small></dd></dl> <p>Regarding even the fine measuring methods presented, there are still errors one may wish remove or at least to consider. Non-linearities of the time-to-digital conversion for example can be identified by taking a large number of measurements of a <a href="/wiki/Poissonian" class="mw-redirect" title="Poissonian">poissonian</a> distributed source (statistical code density test).<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> Small deviations from the uniform distribution reveal the non-linearities. Inconveniently the statistical code density method is quite sensitive to external temperature changes. Thus stabilizing <a href="/wiki/Delay-locked_loop" title="Delay-locked loop">delay</a> or <a href="/wiki/Phase-locked_loop" title="Phase-locked loop">phase-locked loop</a> (DLL or PLL) circuits are recommended. </p><p>In a similar way, offset errors (non-zero readouts at <i>T</i> = 0) can be removed. </p><p>For long time intervals, the error due to instabilities in the <a href="/wiki/Clock_signal" title="Clock signal">reference clock</a> (<a href="/wiki/Jitter" title="Jitter">jitter</a>) plays a major role. Thus clocks of superior quality are needed for such TDCs. </p><p>Furthermore, external noise sources can be eliminated in postprocessing by <a href="/wiki/Robust_statistic" class="mw-redirect" title="Robust statistic">robust estimation methods</a>.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Configurations">Configurations</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=16" title="Edit section: Configurations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>TDCs are currently built as stand-alone measuring devices in physical experiments or as system components like PCI cards. They can be made up of either discrete or integrated circuits. </p><p>Circuit design changes with the purpose of the TDC, which can either be a very good solution for single-shot TDCs with long dead times or some trade-off between dead-time and resolution for multi-shot TDCs. </p> <div class="mw-heading mw-heading2"><h2 id="Delay_generator">Delay generator</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=17" title="Edit section: Delay generator"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:TDC_DTC_000.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/af/TDC_DTC_000.png/220px-TDC_DTC_000.png" decoding="async" width="220" height="157" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/af/TDC_DTC_000.png/330px-TDC_DTC_000.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/af/TDC_DTC_000.png/440px-TDC_DTC_000.png 2x" data-file-width="1389" data-file-height="991" /></a><figcaption>Similarity between a <b>TDC</b> (bottom) and a <b>Delay Generator</b> (top, but needs bottom for trigger). The strobe is gated by the oscillator to avoid a race with the carry bit</figcaption></figure> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Digital_delay_generator" title="Digital delay generator">Digital delay generator</a></div> <p>The time-to-digital converter measures the time between a start event and a stop event. There is also a <b>digital-to-time converter</b> or <b>delay generator</b>. The delay generator converts a number to a time delay. When the delay generator gets a start pulse at its input, then it outputs a stop pulse after the specified delay. The architectures for TDC and delay generators are similar. Both use counters for long, stable, delays. Both must consider the problem of clock quantization errors. </p><p>For example, the <a href="/wiki/Tektronix" title="Tektronix">Tektronix</a> 7D11 Digital Delay uses a counter architecture.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> A digital delay may be set from 100 ns to 1 s in 100 ns increments. An analog circuit provides an additional fine delay of 0 to 100 ns. A 5 MHz reference clock drives a <a href="/wiki/Phase-locked_loop" title="Phase-locked loop">phase-locked loop</a> to produce a stable 500 MHz clock. It is this fast clock that is gated by the (fine-delayed) start event and determines the main quantization error. The fast clock is divided down to 10 MHz and fed to main counter.<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> The instrument quantization error depends primarily on the 500 MHz clock (2 ns steps), but other errors also enter; the instrument is specified to have 2.2 ns of <a href="/wiki/Jitter" title="Jitter">jitter</a>. The recycle time is 575 ns. </p><p>Just as a TDC may use interpolation to get finer than one clock period resolution, a delay generator may use similar techniques. The <a href="/wiki/Hewlett-Packard" title="Hewlett-Packard">Hewlett-Packard</a> 5359A High Resolution Time Synthesizer provides delays of 0 to 160 ms, has an accuracy of 1 ns, and achieves a typical jitter of 100 ps.<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> The design uses a triggered phase-locked oscillator that runs at 200 MHz. Interpolation is done with a ramp, an 8-bit digital-to-analog converter, and a comparator. The resolution is about 45 ps. </p><p>When the start pulse is received, then <a href="/wiki/Counter_(digital)" title="Counter (digital)">counts</a> down and outputs a stop pulse. For low <a href="/wiki/Jitter" title="Jitter">jitter</a> the <a href="/wiki/Counter_(digital)" title="Counter (digital)">synchronous counter</a> has to feed a <a href="/wiki/Status_register" title="Status register">zero flag</a> from the <a href="/wiki/Most_significant_bit" class="mw-redirect" title="Most significant bit">most significant bit</a> down to the <a href="/wiki/Least_significant_bit" class="mw-redirect" title="Least significant bit">least significant bit</a> and then combine it with the output from the Johnson counter. </p><p>A <a href="/wiki/Digital-to-analog_converter" title="Digital-to-analog converter">digital-to-analog converter</a> (DAC) could be used to achieve sub-cycle resolution, but it is easier to either use vernier Johnson counters or traveling-wave Johnson counters. </p><p>The delay generator can be used for <a href="/wiki/Pulse-width_modulation" title="Pulse-width modulation">pulse-width modulation</a>, e.g. to drive a <a href="/wiki/MOSFET" title="MOSFET">MOSFET</a> to load a <a href="/wiki/Pockels_cell" class="mw-redirect" title="Pockels cell">Pockels cell</a> within 8 ns with a specific charge. </p><p>The output of a delay generator can gate a digital-to-analog converter and so pulses of a variable height can be generated. This allows matching to low levels needed by analog electronics, higher levels for <a href="/wiki/Emitter-coupled_logic" title="Emitter-coupled logic">ECL</a> and even higher levels for <a href="/wiki/Transistor%E2%80%93transistor_logic" title="Transistor–transistor logic">TTL</a>. If a series of DACs is gated in sequence, variable pulse shapes can be generated to account for any transfer function. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=18" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Sampling_frequency" class="mw-redirect" title="Sampling frequency">Sampling frequency</a></li> <li><a href="/wiki/Multivibrator" title="Multivibrator">Multivibrator</a></li> <li><a href="/wiki/LIDAR" class="mw-redirect" title="LIDAR">LIDAR</a></li> <li><a href="/wiki/Time-of-flight" class="mw-redirect" title="Time-of-flight">Time-of-flight</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=19" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-Kalisz-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-Kalisz_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Kalisz_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Kalisz_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Kalisz_1-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Kalisz_1-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Kalisz_1-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFKalisz2004" class="citation cs2">Kalisz, Józef (February 2004), "Review of methods for time interval measurements with picosecond resolution", <i>Metrologia</i>, <b>41</b> (1), Institute of Physics Publishing: 17–32, <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2004Metro..41...17K">2004Metro..41...17K</a>, <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F0026-1394%2F41%2F1%2F004">10.1088/0026-1394/41/1/004</a>, <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:250775541">250775541</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Metrologia&rft.atitle=Review+of+methods+for+time+interval+measurements+with+picosecond+resolution&rft.volume=41&rft.issue=1&rft.pages=17-32&rft.date=2004-02&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A250775541%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1088%2F0026-1394%2F41%2F1%2F004&rft_id=info%3Abibcode%2F2004Metro..41...17K&rft.aulast=Kalisz&rft.aufirst=J%C3%B3zef&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKris_Ardis2019" class="citation techreport cs1">Kris Ardis (2019-02-06). <a rel="nofollow" class="external text" href="https://pdfserv.maximintegrated.com/en/an/AN5968.pdf"><i>Maxim Integrated Application Note 5968 (Welcoming water metering into the 21st century)</i></a> <span class="cs1-format">(PDF)</span> (Technical report). Analog Devices.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Maxim+Integrated+Application+Note+5968+%28Welcoming+water+metering+into+the+21st+century%29&rft.pub=Analog+Devices&rft.date=2019-02-06&rft.au=Kris+Ardis&rft_id=https%3A%2F%2Fpdfserv.maximintegrated.com%2Fen%2Fan%2FAN5968.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation techreport cs1"><a rel="nofollow" class="external text" href="https://www.sciosense.com/wp-content/uploads/documents/TDC-GP30-Application-Note-Water-heat-metering.pdf"><i>Ultrasonic Flow Converters Application Note 023. Ultrasonic Water & Heat Metering with TDC-GP22</i></a> <span class="cs1-format">(PDF)</span> (Technical report). ams AG. 2013-07-10.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Ultrasonic+Flow+Converters+Application+Note+023.+Ultrasonic+Water+%26+Heat+Metering+with+TDC-GP22&rft.pub=ams+AG&rft.date=2013-07-10&rft_id=https%3A%2F%2Fwww.sciosense.com%2Fwp-content%2Fuploads%2Fdocuments%2FTDC-GP30-Application-Note-Water-heat-metering.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-Henzler_2010_Section_6.1-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-Henzler_2010_Section_6.1_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHenzler2010" class="citation book cs1">Henzler, Stephan (2010). "6.1 Digital Phase Locked Loop". <i>Time-to-Digital Converters</i>. Springer Series in Advanced Microelectronics. Vol. 29. Dordrecht: Springer Netherlands. pp. 112–116. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-90-481-8628-0">10.1007/978-90-481-8628-0</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-90-481-8627-3" title="Special:BookSources/978-90-481-8627-3"><bdi>978-90-481-8627-3</bdi></a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1437-0387">1437-0387</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=6.1+Digital+Phase+Locked+Loop&rft.btitle=Time-to-Digital+Converters&rft.place=Dordrecht&rft.series=Springer+Series+in+Advanced+Microelectronics&rft.pages=112-116&rft.pub=Springer+Netherlands&rft.date=2010&rft.issn=1437-0387&rft_id=info%3Adoi%2F10.1007%2F978-90-481-8628-0&rft.isbn=978-90-481-8627-3&rft.aulast=Henzler&rft.aufirst=Stephan&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">For example, a Hewlett-Packard (now Agilent) 10811 crystal oven oscillator; <a rel="nofollow" class="external free" href="http://www.hparchive.com/Manuals/HP-10811AB-Manual.pdf">http://www.hparchive.com/Manuals/HP-10811AB-Manual.pdf</a></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2"><a rel="nofollow" class="external text" href="http://tf.nist.gov/general/enc-ti.htm"><i>Time and Frequency from A to Z</i></a>, National Institute of Standards and Technology, <q>For example, multiplying the time base frequency to 100 MHz makes 10 ns resolution possible, and 1 ns counters have even been built using a 1 GHz time base. However, a more common way to increase resolution is to detect parts of a time base cycle through interpolation and not be limited by the number of whole cycles. Interpolation has made 1 ns TICs commonplace, and even 20 picosecond TICs are available.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Time+and+Frequency+from+A+to+Z&rft.pub=National+Institute+of+Standards+and+Technology&rft_id=http%3A%2F%2Ftf.nist.gov%2Fgeneral%2Fenc-ti.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span>, entry for <i>time interval counter</i>.</span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><a href="#CITEREFKalisz2004">Kalisz 2004</a>, p. 19</span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFReeser1969" class="citation cs2">Reeser, Gilbert A. (May 1969), <a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1969-05.pdf">"An Electronic Counter for the 1970's"</a> <span class="cs1-format">(PDF)</span>, <i>Hewlett-Packard Journal</i>, <b>20</b> (9), Hewlett-Packard: 9–12</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Hewlett-Packard+Journal&rft.atitle=An+Electronic+Counter+for+the+1970%27s&rft.volume=20&rft.issue=9&rft.pages=9-12&rft.date=1969-05&rft.aulast=Reeser&rft.aufirst=Gilbert+A.&rft_id=http%3A%2F%2Fwww.hpl.hp.com%2Fhpjournal%2Fpdfs%2FIssuePDFs%2F1969-05.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-Sasaki-9"><span class="mw-cite-backlink">^ <a href="#cite_ref-Sasaki_9-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Sasaki_9-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSasakiJensen1980" class="citation cs2">Sasaki, Gary D.; Jensen, Ronald C. (September 1980), <a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1980-09.pdf">"Automatic Measurements with a High Performance Universal Counter"</a> <span class="cs1-format">(PDF)</span>, <i>Hewlett-Packard Journal</i>, <b>31</b> (9), Hewlett-Packard: 21–31</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Hewlett-Packard+Journal&rft.atitle=Automatic+Measurements+with+a+High+Performance+Universal+Counter&rft.volume=31&rft.issue=9&rft.pages=21-31&rft.date=1980-09&rft.aulast=Sasaki&rft.aufirst=Gary+D.&rft.au=Jensen%2C+Ronald+C.&rft_id=http%3A%2F%2Fwww.hpl.hp.com%2Fhpjournal%2Fpdfs%2FIssuePDFs%2F1980-09.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRushOldfield1986" class="citation cs2">Rush, Kenneth; Oldfield, Danny J. (April 1986), "A Data Acquisition System for a 1-GHz Digitizing Oscilloscope", <i>Hewlett-Packard Journal</i>, <b>37</b> (4), Hewlett-Packard: 4–11</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Hewlett-Packard+Journal&rft.atitle=A+Data+Acquisition+System+for+a+1-GHz+Digitizing+Oscilloscope&rft.volume=37&rft.issue=4&rft.pages=4-11&rft.date=1986-04&rft.aulast=Rush&rft.aufirst=Kenneth&rft.au=Oldfield%2C+Danny+J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-HP1-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-HP1_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-HP1_11-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFEskeldsonKellumWhiteman1993" class="citation cs2">Eskeldson, David D.; Kellum, Reginald; Whiteman, Donald A. (October 1993), "A Digitizing Oscilloscope Time Base and Trigger System Optimized for Throughput and Low Jitter", <i>Hewlett-Packard Journal</i>, <b>44</b> (5), Hewlett-Packard: 21–30</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Hewlett-Packard+Journal&rft.atitle=A+Digitizing+Oscilloscope+Time+Base+and+Trigger+System+Optimized+for+Throughput+and+Low+Jitter&rft.volume=44&rft.issue=5&rft.pages=21-30&rft.date=1993-10&rft.aulast=Eskeldson&rft.aufirst=David+D.&rft.au=Kellum%2C+Reginald&rft.au=Whiteman%2C+Donald+A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><a href="#CITEREFKalisz2004">Kalisz 2004</a>, p. 20. Kalisz states that the <a href="/wiki/Stanford_Research_Systems" title="Stanford Research Systems">Stanford Research Systems</a> SR620 uses this method.</span> </li> <li id="cite_note-Esk_p27-13"><span class="mw-cite-backlink">^ <a href="#cite_ref-Esk_p27_13-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Esk_p27_13-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Esk_p27_13-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFEskeldsonKellumWhiteman1993">Eskeldson, Kellum & Whiteman 1993</a>, p. 27 stating, "Effectively, the interpolator magnifies the interpolation or uncertainty interval by the ratio of the charge and discharge currents."</span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><a href="#CITEREFEskeldsonKellumWhiteman1993">Eskeldson, Kellum & Whiteman 1993</a>, p. 27</span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><a href="#CITEREFSasakiJensen1980">Sasaki & Jensen 1980</a>, p. 23 stating, "In practice, the current sources and other circuitry used to build the interpolators are subject to operational variations over temperature and time. The 5360A's interpolators were in a special insulated cavity and had several adjustments. The 5335A uses a self-calibration technique that is not affected by temperature and needs no adjustments."</span> </li> <li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChuAllenFoster1978" class="citation cs2">Chu, David C.; Allen, Mark S.; Foster, Allen S. (August 1978), <a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1978-08.pdf">"Universal Counter Resolves Picoseconds in Time Interval Measurements"</a> <span class="cs1-format">(PDF)</span>, <i>HP Journal</i>, <b>29</b> (12), Hewlett-Packard: 2–11</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=HP+Journal&rft.atitle=Universal+Counter+Resolves+Picoseconds+in+Time+Interval+Measurements&rft.volume=29&rft.issue=12&rft.pages=2-11&rft.date=1978-08&rft.aulast=Chu&rft.aufirst=David+C.&rft.au=Allen%2C+Mark+S.&rft.au=Foster%2C+Allen+S.&rft_id=http%3A%2F%2Fwww.hpl.hp.com%2Fhpjournal%2Fpdfs%2FIssuePDFs%2F1978-08.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChu1978" class="citation cs2">Chu, David C. (August 1978), <a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1978-08.pdf">"The Triggered Phase-Locked Oscillator"</a> <span class="cs1-format">(PDF)</span>, <i>HP Journal</i>, <b>29</b> (12), Hewlett-Packard: 8–9</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=HP+Journal&rft.atitle=The+Triggered+Phase-Locked+Oscillator&rft.volume=29&rft.issue=12&rft.pages=8-9&rft.date=1978-08&rft.aulast=Chu&rft.aufirst=David+C.&rft_id=http%3A%2F%2Fwww.hpl.hp.com%2Fhpjournal%2Fpdfs%2FIssuePDFs%2F1978-08.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-Henzler_2010_Section_5.3-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-Henzler_2010_Section_5.3_18-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHenzler2010" class="citation book cs1">Henzler, Stephan (2010). "5.3 Vernier TDC". <i>Time-to-Digital Converters</i>. Springer Series in Advanced Microelectronics. Vol. 29. Dordrecht: Springer Netherlands. pp. 83–85. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-90-481-8628-0">10.1007/978-90-481-8628-0</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-90-481-8627-3" title="Special:BookSources/978-90-481-8627-3"><bdi>978-90-481-8627-3</bdi></a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1437-0387">1437-0387</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=5.3+Vernier+TDC&rft.btitle=Time-to-Digital+Converters&rft.place=Dordrecht&rft.series=Springer+Series+in+Advanced+Microelectronics&rft.pages=83-85&rft.pub=Springer+Netherlands&rft.date=2010&rft.issn=1437-0387&rft_id=info%3Adoi%2F10.1007%2F978-90-481-8628-0&rft.isbn=978-90-481-8627-3&rft.aulast=Henzler&rft.aufirst=Stephan&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-Henzler_2010_Section_2.4-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-Henzler_2010_Section_2.4_19-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHenzler2010" class="citation book cs1">Henzler, Stephan (2010). "2.4 Basic Digital Delay-Line Based TDC". <i>Time-to-Digital Converters</i>. Springer Series in Advanced Microelectronics. Vol. 29. Dordrecht: Springer Netherlands. pp. 22–26. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-90-481-8628-0">10.1007/978-90-481-8628-0</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-90-481-8627-3" title="Special:BookSources/978-90-481-8627-3"><bdi>978-90-481-8627-3</bdi></a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1437-0387">1437-0387</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=2.4+Basic+Digital+Delay-Line+Based+TDC&rft.btitle=Time-to-Digital+Converters&rft.place=Dordrecht&rft.series=Springer+Series+in+Advanced+Microelectronics&rft.pages=22-26&rft.pub=Springer+Netherlands&rft.date=2010&rft.issn=1437-0387&rft_id=info%3Adoi%2F10.1007%2F978-90-481-8628-0&rft.isbn=978-90-481-8627-3&rft.aulast=Henzler&rft.aufirst=Stephan&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKaliszPawlowskiPelka1987" class="citation cs2">Kalisz, J.; Pawlowski, M.; Pelka, R. (1987), "Error analysis and design of the Nutt time-interval digitiser with picosecond resolution", <i>J. Phys. E: Sci. Instrum.</i>, <b>20</b> (11): 1330–1341, <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1987JPhE...20.1330K">1987JPhE...20.1330K</a>, <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F0022-3735%2F20%2F11%2F005">10.1088/0022-3735/20/11/005</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=J.+Phys.+E%3A+Sci.+Instrum.&rft.atitle=Error+analysis+and+design+of+the+Nutt+time-interval+digitiser+with+picosecond+resolution&rft.volume=20&rft.issue=11&rft.pages=1330-1341&rft.date=1987&rft_id=info%3Adoi%2F10.1088%2F0022-3735%2F20%2F11%2F005&rft_id=info%3Abibcode%2F1987JPhE...20.1330K&rft.aulast=Kalisz&rft.aufirst=J.&rft.au=Pawlowski%2C+M.&rft.au=Pelka%2C+R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text">"Bruno Benedetto Rossi", George W. Clark, National Academic Press, Washington D.C. 1998, S.13</span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text">"Noise Shaping Techniques for Analog and Time to Digital Converters Using Voltage Controlled Oscillators", Matthew A.Z. Straayer, Phd-Thesis, Massachusetts Institute of Technology (2008)</span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPelkaKaliszSzplet1997" class="citation cs2">Pelka, R.; Kalisz, J.; Szplet, R. (1997), "Nonlinearity correction of the integrated time-to-digital converter with direct coding", <i>IEEE Transactions on Instrumentation and Measurement</i>, <b>46</b> (2): 449–452, <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1997ITIM...46..449P">1997ITIM...46..449P</a>, <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2F19.571882">10.1109/19.571882</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Transactions+on+Instrumentation+and+Measurement&rft.atitle=Nonlinearity+correction+of+the+integrated+time-to-digital+converter+with+direct+coding&rft.volume=46&rft.issue=2&rft.pages=449-452&rft.date=1997&rft_id=info%3Adoi%2F10.1109%2F19.571882&rft_id=info%3Abibcode%2F1997ITIM...46..449P&rft.aulast=Pelka&rft.aufirst=R.&rft.au=Kalisz%2C+J.&rft.au=Szplet%2C+R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKaliszPawlowskiPelka1994" class="citation cs2">Kalisz, J.; Pawlowski, M.; Pelka, R. (March 1994), "Precision time counter for laser ranging to satellites", <i>Rev. Sci. Instrum.</i>, <b>65</b> (3): 736–741, <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1994RScI...65..736K">1994RScI...65..736K</a>, <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1063%2F1.1145094">10.1063/1.1145094</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Rev.+Sci.+Instrum.&rft.atitle=Precision+time+counter+for+laser+ranging+to+satellites&rft.volume=65&rft.issue=3&rft.pages=736-741&rft.date=1994-03&rft_id=info%3Adoi%2F10.1063%2F1.1145094&rft_id=info%3Abibcode%2F1994RScI...65..736K&rft.aulast=Kalisz&rft.aufirst=J.&rft.au=Pawlowski%2C+M.&rft.au=Pelka%2C+R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2"><i>Tektronix 7D11 Digital Delay Service Instruction Manual</i>, Beaverton, OR: Tektronix, 1973, 070-1377-01</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Tektronix+7D11+Digital+Delay+Service+Instruction+Manual&rft.place=Beaverton%2C+OR&rft.pub=Tektronix&rft.date=1973&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text">Ten megahertz is a frequency that TTL logic in 1971 could handle. The high frequency divisions were handled with different technologies because high speed digital counters were uncommon in 1971. The first (500 MHz) divider stage is a 100 MHz synchronized <a href="/wiki/Multivibrator" title="Multivibrator">multivibrator</a> to effect a divide by 5 circuit. The second (100 MHz) stage is a divide by 5 ring counter made from discrete emitter-coupled transistors. The last stage is a flip-flop.</span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFergusonDickstein1978" class="citation cs2">Ferguson, Keith M.; Dickstein, Leonard R. (August 1978), <a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1978-08.pdf">"Time Synthesizer Generates Precise Pulse Widths and Time Delays for Critical Timing Applications"</a> <span class="cs1-format">(PDF)</span>, <i>HP Journal</i>, <b>29</b> (12): 12–19</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=HP+Journal&rft.atitle=Time+Synthesizer+Generates+Precise+Pulse+Widths+and+Time+Delays+for+Critical+Timing+Applications&rft.volume=29&rft.issue=12&rft.pages=12-19&rft.date=1978-08&rft.aulast=Ferguson&rft.aufirst=Keith+M.&rft.au=Dickstein%2C+Leonard+R.&rft_id=http%3A%2F%2Fwww.hpl.hp.com%2Fhpjournal%2Fpdfs%2FIssuePDFs%2F1978-08.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Time-to-digital_converter&action=edit&section=20" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><style data-mw-deduplicate="TemplateStyles:r1041539562">.mw-parser-output .citation{word-wrap:break-word}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}</style><span class="citation patent"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US3983481">US 3983481</a>, Nutt, Ronald; Milam, Kelly & Williams, Charles W., "Digital intervalometer", published 4 August 1975, issued 18 September 1976</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=3983481&rft.cc=US&rft.title=Digital+intervalometer&rft.inventor=Nutt&rft.date=18 September 1976&rft.pubdate=4 August 1975"><span style="display: none;"> </span></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1041539562"><span class="citation patent"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US3133189">US 3133189</a>, Bagley, Alan S. & Brooksby, Merrill W., "Electronic Interpolating Counter for the Time Interval and Frequency Measurement", published 5 August 1960, issued 12 May 1964</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=3133189&rft.cc=US&rft.title=Electronic+Interpolating+Counter+for+the+Time+Interval+and+Frequency+Measurement&rft.inventor=Bagley&rft.date=12 May 1964&rft.pubdate=5 August 1960"><span style="display: none;"> </span></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1041539562"><span class="citation patent"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US2665411">US 2665411</a>, Frady, William E., Jr., "Double Interpolation Method and Apparatus for Measuring Time Intervals", published 15 March 1951, issued 5 January 1954</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=2665411&rft.cc=US&rft.title=Double+Interpolation+Method+and+Apparatus+for+Measuring+Time+Intervals&rft.inventor=Frady&rft.date=5 January 1954&rft.pubdate=15 March 1951"><span style="display: none;"> </span></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1041539562"><span class="citation patent"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US2665410">US 2665410</a>, Burbeck, Donald W., "Method and Apparatus for Automatically Measuring Time Intervals", published 15 March 1951, issued 5 January 1954</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=2665410&rft.cc=US&rft.title=Method+and+Apparatus+for+Automatically+Measuring+Time+Intervals&rft.inventor=Burbeck&rft.date=5 January 1954&rft.pubdate=15 March 1951"><span style="display: none;"> </span></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1041539562"><span class="citation patent"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US2560124">US 2560124</a>, Mofenson, Jack, "Interval Measuring System", published 31 March 1950, issued 10 July 1951</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=2560124&rft.cc=US&rft.title=Interval+Measuring+System&rft.inventor=Mofenson&rft.date=10 July 1951&rft.pubdate=31 March 1950"><span style="display: none;"> </span></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1041539562"><span class="citation patent"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US8324952">US 8324952</a>, Masters, Lewis W., "Time interpolator circuit", published 2012-12-04, issued 2011-05-04</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=8324952&rft.cc=US&rft.title=Time+interpolator+circuit&rft.inventor=Masters&rft.date=2011-05-04&rft.pubdate=2012-12-04"><span style="display: none;"> </span></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation conference cs1">Le Grand de Mercey, G. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110709121126/http://forschung.unibw-muenchen.de/papers/3qvttjtopxog1op34ojasir046besi.pdf">"A 18GHz rotary traveling wave VCO in CMOS with I/Q outputs"</a> <span class="cs1-format">(PDF)</span>. <i>ESSCIRC 2004 - 29th European Solid-State Circuits Conference (IEEE Cat. No.03EX705)</i>. IEEE. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2Fesscirc.2003.1257179">10.1109/esscirc.2003.1257179</a>. Archived from <a rel="nofollow" class="external text" href="http://forschung.unibw-muenchen.de/papers/3qvttjtopxog1op34ojasir046besi.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2011-07-09.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=A+18GHz+rotary+traveling+wave+VCO+in+CMOS+with+I%2FQ+outputs&rft.btitle=ESSCIRC+2004+-+29th+European+Solid-State+Circuits+Conference+%28IEEE+Cat.+No.03EX705%29&rft.pub=IEEE&rft_id=info%3Adoi%2F10.1109%2Fesscirc.2003.1257179&rft.aulast=Le+Grand+de+Mercey&rft.aufirst=G.&rft_id=http%3A%2F%2Fforschung.unibw-muenchen.de%2Fpapers%2F3qvttjtopxog1op34ojasir046besi.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation conference cs1">Bhattacharyya, K.; Szymanski, T.H. <a rel="nofollow" class="external text" href="http://www.ece.mcmaster.ca/faculty/teds/PAPERS_folder/IEEE_RAWCON.pdf">"1.2 V CMOS 1-10 GHz traveling wave amplifiers using coplanar waveguides as on-chip inductors"</a> <span class="cs1-format">(PDF)</span>. <i>Proceedings. 2004 IEEE Radio and Wireless Conference (IEEE Cat. No.04TH8746)</i>. IEEE. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2Frawcon.2004.1389112">10.1109/rawcon.2004.1389112</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=1.2+V+CMOS+1-10+GHz+traveling+wave+amplifiers+using+coplanar+waveguides+as+on-chip+inductors&rft.btitle=Proceedings.+2004+IEEE+Radio+and+Wireless+Conference+%28IEEE+Cat.+No.04TH8746%29&rft.pub=IEEE&rft_id=info%3Adoi%2F10.1109%2Frawcon.2004.1389112&rft.aulast=Bhattacharyya&rft.aufirst=K.&rft.au=Szymanski%2C+T.H.&rft_id=http%3A%2F%2Fwww.ece.mcmaster.ca%2Ffaculty%2Fteds%2FPAPERS_folder%2FIEEE_RAWCON.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1">John Ackermann (2020-11-28). <a rel="nofollow" class="external text" href="http://www.febo.com/pages/hp5370b/">"The HP 5370B Time Interval Counter [application notes and measured performance]"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-09-26</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+HP+5370B+Time+Interval+Counter+%5Bapplication+notes+and+measured+performance%5D&rft.date=2020-11-28&rft.au=John+Ackermann&rft_id=http%3A%2F%2Fwww.febo.com%2Fpages%2Fhp5370b%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20170316030027/http://www.g8wrb.org/useful-stuff/time/HP-5370B/">"Data sheets, manuals and application notes on [mainly HP] time-interval counters"</a>. 2017-03-16. Archived from <a rel="nofollow" class="external text" href="http://www.g8wrb.org/useful-stuff/time/HP-5370B/">the original</a> on 2017-03-16<span class="reference-accessdate">. Retrieved <span class="nowrap">2017-03-16</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Data+sheets%2C+manuals+and+application+notes+on+%5Bmainly+HP%5D+time-interval+counters&rft.date=2017-03-16&rft_id=http%3A%2F%2Fwww.g8wrb.org%2Fuseful-stuff%2Ftime%2FHP-5370B%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFYu._ArtyukhV._Bespal'koE._Boole" class="citation techreport cs1">Yu. Artyukh; V. Bespal'ko; E. Boole. <a rel="nofollow" class="external text" href="https://ilrs.gsfc.nasa.gov/docs/timing/artyukh_time_interval_counter.pdf"><i>High Resolution Modular Time Interval Counter</i></a> <span class="cs1-format">(PDF)</span> (Technical report)<span class="reference-accessdate">. Retrieved <span class="nowrap">2002-12-04</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=High+Resolution+Modular+Time+Interval+Counter&rft.au=Yu.+Artyukh&rft.au=V.+Bespal%27ko&rft.au=E.+Boole&rft_id=http%3A%2F%2Filrs.gsfc.nasa.gov%2Fdocs%2Ftiming%2Fartyukh_time_interval_counter.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation techreport cs1"><a rel="nofollow" class="external text" href="https://ilrs.gsfc.nasa.gov/docs/time_interval_measurements.pdf"><i>Fundamentals of Time Interval Measurements (Application Note 200-3)</i></a> <span class="cs1-format">(PDF)</span> (Technical report). Electronic Counter Series. HP.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Fundamentals+of+Time+Interval+Measurements+%28Application+Note+200-3%29&rft.series=Electronic+Counter+Series&rft.pub=HP&rft_id=http%3A%2F%2Filrs.gsfc.nasa.gov%2Fdocs%2Ftime_interval_measurements.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation conference cs1">Zhang, Victor S.; Davis, Dick D.; Lombardi, Michael A. (1994-12-01). <a rel="nofollow" class="external text" href="https://apps.dtic.mil/sti/pdfs/ADA494734.pdf"><i>High Resolution Time Interval Counter</i></a> <span class="cs1-format">(PDF)</span>. The 26th Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting. Defense Technical Information Center/NASA. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1995ptti.meet..191Z">1995ptti.meet..191Z</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=High+Resolution+Time+Interval+Counter&rft.pub=Defense+Technical+Information+Center%2FNASA&rft.date=1994-12-01&rft_id=info%3Abibcode%2F1995ptti.meet..191Z&rft.aulast=Zhang&rft.aufirst=Victor+S.&rft.au=Davis%2C+Dick+D.&rft.au=Lombardi%2C+Michael+A.&rft_id=https%3A%2F%2Fapps.dtic.mil%2Fsti%2Fpdfs%2FADA494734.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2">Salvatore, Loffredo (2010), <i>Design, construction and tests of a high resolution, high dynamic range Time to Digital Converter</i></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Design%2C+construction+and+tests+of+a+high+resolution%2C+high+dynamic+range+Time+to+Digital+Converter&rft.date=2010&rft.aulast=Salvatore&rft.aufirst=Loffredo&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span> Università degli studi Roma Tre, Scuola Dottorale in Scienze Matematiche e Fisiche</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2">Kalisz, Jozef; Szplet, Ryszard; Pelka, Ryszard (August 1997), "Single-Chip Interpolating Time Counter with 200-ps Resolution and 43-s Range", <i>IEEE Transactions on Instrumentation and Measurement</i>, <b>46</b> (4), IEEE: 851–856, <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1997ITIM...46..851K">1997ITIM...46..851K</a>, <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2F19.650787">10.1109/19.650787</a>, <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0018-9456">0018-9456</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Transactions+on+Instrumentation+and+Measurement&rft.atitle=Single-Chip+Interpolating+Time+Counter+with+200-ps+Resolution+and+43-s+Range&rft.volume=46&rft.issue=4&rft.pages=851-856&rft.date=1997-08&rft.issn=0018-9456&rft_id=info%3Adoi%2F10.1109%2F19.650787&rft_id=info%3Abibcode%2F1997ITIM...46..851K&rft.aulast=Kalisz&rft.aufirst=Jozef&rft.au=Szplet%2C+Ryszard&rft.au=Pelka%2C+Ryszard&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation techreport cs1"><a rel="nofollow" class="external text" href="http://www.ti.com/lit/ds/symlink/tdc7200.pdf"><i>TDC7200 Time-to-Digital Converter for Time-of-Flight Applications in LIDAR, Magnetostrictive and Flow Meters [Datasheet]</i></a> <span class="cs1-format">(PDF)</span> (Technical report). TI. 2016-03-01.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=TDC7200+Time-to-Digital+Converter+for+Time-of-Flight+Applications+in+LIDAR%2C+Magnetostrictive+and+Flow+Meters+%5BDatasheet%5D&rft.pub=TI&rft.date=2016-03-01&rft_id=http%3A%2F%2Fwww.ti.com%2Flit%2Fds%2Fsymlink%2Ftdc7200.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ATime-to-digital+converter" class="Z3988"></span></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Electrical_and_electronic_measuring_equipment" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Electrical_and_electronic_measuring_equipment" title="Template:Electrical and electronic measuring equipment"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Electrical_and_electronic_measuring_equipment" title="Template talk:Electrical and electronic measuring equipment"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Electrical_and_electronic_measuring_equipment" title="Special:EditPage/Template:Electrical and electronic measuring equipment"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Electrical_and_electronic_measuring_equipment" style="font-size:114%;margin:0 4em"><a href="/wiki/List_of_electrical_and_electronic_measuring_equipment" title="List of electrical and electronic measuring equipment">Electrical and electronic measuring equipment</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Metering</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ammeter" title="Ammeter">Ammeter</a></li> <li><a href="/wiki/Capacitance_meter" title="Capacitance meter">Capacitance meter</a></li> <li><a href="/wiki/Distortionmeter" title="Distortionmeter">Distortionmeter</a></li> <li><a href="/wiki/Electricity_meter" title="Electricity meter">Electricity meter</a></li> <li><a href="/wiki/Frequency_counter" title="Frequency counter">Frequency counter</a></li> <li><a href="/wiki/Galvanometer" title="Galvanometer">Galvanometer</a></li> <li><a href="/wiki/LCR_meter" title="LCR meter">LCR meter</a></li> <li><a href="/wiki/Microwave_power_meter" title="Microwave power meter">Microwave power meter</a></li> <li><a href="/wiki/Multimeter" title="Multimeter">Multimeter</a></li> <li><a href="/wiki/Megohmmeter" title="Megohmmeter">Megohmmeter</a></li> <li><a href="/wiki/Ohmmeter" title="Ohmmeter">Ohmmeter</a></li> <li><a href="/wiki/Peak_meter" title="Peak meter">Peak meter</a></li> <li><a href="/wiki/Peak_programme_meter" title="Peak programme meter">Peak programme meter</a></li> <li><a href="/wiki/Psophometer" title="Psophometer">Psophometer</a></li> <li><a href="/wiki/Q_meter" title="Q meter">Q meter</a></li> <li><a href="/wiki/Time-domain_reflectometer" title="Time-domain reflectometer">Time-domain reflectometer</a></li> <li><a class="mw-selflink selflink">Time-to-digital converter</a></li> <li><a href="/wiki/Transformer_ratio_arm_bridge" title="Transformer ratio arm bridge">Transformer ratio arm bridge</a></li> <li><a href="/wiki/Transistor_tester" title="Transistor tester">Transistor tester</a></li> <li><a href="/wiki/Tube_tester" title="Tube tester">Tube tester</a></li> <li><a href="/wiki/Wattmeter" title="Wattmeter">Wattmeter</a></li> <li><a href="/wiki/Voltmeter" title="Voltmeter">Voltmeter</a></li> <li><a href="/wiki/VU_meter" title="VU meter">VU meter</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Analysis</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bus_analyzer" title="Bus analyzer">Bus analyzer</a></li> <li><a href="/wiki/Logic_analyzer" title="Logic analyzer">Logic analyzer</a></li> <li><a href="/wiki/Network_analyzer_(electrical)" title="Network analyzer (electrical)">Network analyzer</a></li> <li><a href="/wiki/Oscilloscope" title="Oscilloscope">Oscilloscope</a></li> <li><a href="/wiki/Signal_analyzer" title="Signal analyzer">Signal analyzer</a></li> <li><a href="/wiki/Spectrum_analyzer" title="Spectrum analyzer">Spectrum analyzer</a></li> <li><a href="/wiki/Waveform_monitor" title="Waveform monitor">Waveform monitor</a></li> <li><a href="/wiki/Vectorscope" title="Vectorscope">Vectorscope</a></li> <li><a href="/wiki/Video_borescope" class="mw-redirect" title="Video borescope">Video borescope</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Generation</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Arbitrary_waveform_generator" title="Arbitrary waveform generator">Arbitrary waveform generator</a></li> <li><a href="/wiki/Digital_pattern_generator" title="Digital pattern generator">Digital pattern generator</a></li> <li><a href="/wiki/Function_generator" title="Function generator">Function generator</a></li> <li><a href="/wiki/Sweep_generator" title="Sweep generator">Sweep generator</a></li> <li><a href="/wiki/Signal_generator" title="Signal generator">Signal generator</a></li> <li><a href="/wiki/Video-signal_generator" title="Video-signal generator">Video-signal generator</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Time-to-digital_converter&oldid=1214307871">https://en.wikipedia.org/w/index.php?title=Time-to-digital_converter&oldid=1214307871</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Digital_circuits" title="Category:Digital circuits">Digital circuits</a></li><li><a href="/wiki/Category:Digital_signal_processing" title="Category:Digital signal processing">Digital signal processing</a></li><li><a href="/wiki/Category:Measuring_instruments" title="Category:Measuring instruments">Measuring instruments</a></li><li><a href="/wiki/Category:Radio_electronics" title="Category:Radio electronics">Radio electronics</a></li><li><a href="/wiki/Category:Signal_processing" title="Category:Signal processing">Signal processing</a></li><li><a href="/wiki/Category:Time" title="Category:Time">Time</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_needing_additional_references_from_November_2012" title="Category:Articles needing additional references from November 2012">Articles needing additional references from November 2012</a></li><li><a href="/wiki/Category:All_articles_needing_additional_references" title="Category:All articles needing additional references">All articles needing additional references</a></li><li><a href="/wiki/Category:Articles_lacking_in-text_citations_from_May_2009" title="Category:Articles lacking in-text citations from May 2009">Articles lacking in-text citations from May 2009</a></li><li><a href="/wiki/Category:All_articles_lacking_in-text_citations" title="Category:All articles lacking in-text citations">All articles lacking in-text citations</a></li><li><a href="/wiki/Category:Articles_with_multiple_maintenance_issues" title="Category:Articles with multiple maintenance issues">Articles with multiple maintenance issues</a></li><li><a href="/wiki/Category:All_articles_with_unsourced_statements" title="Category:All articles with unsourced statements">All articles with unsourced statements</a></li><li><a href="/wiki/Category:Articles_with_unsourced_statements_from_March_2012" title="Category:Articles with unsourced statements from March 2012">Articles with unsourced statements from March 2012</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 18 March 2024, at 04:32<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Time-to-digital_converter&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-76dfdc59c8-drqnm","wgBackendResponseTime":167,"wgPageParseReport":{"limitreport":{"cputime":"0.687","walltime":"0.907","ppvisitednodes":{"value":4677,"limit":1000000},"postexpandincludesize":{"value":109800,"limit":2097152},"templateargumentsize":{"value":14242,"limit":2097152},"expansiondepth":{"value":18,"limit":100},"expensivefunctioncount":{"value":5,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":110747,"limit":5000000},"entityaccesscount":{"value":0,"limit":400},"timingprofile":["100.00% 710.835 1 -total"," 41.22% 293.040 1 Template:Reflist"," 25.67% 182.453 15 Template:Citation"," 17.72% 125.968 1 Template:Multiple_issues"," 16.33% 116.074 1 Template:Electrical_and_electronic_measuring_equipment"," 12.68% 90.154 1 Template:Navbox"," 8.76% 62.260 2 Template:Ambox"," 8.31% 59.066 1 Template:More_citations_needed"," 6.95% 49.387 5 Template:Harvnb"," 5.12% 36.409 6 Template:Cite_patent"]},"scribunto":{"limitreport-timeusage":{"value":"0.417","limit":"10.000"},"limitreport-memusage":{"value":7312307,"limit":52428800},"limitreport-logs":"anchor_id_list = table#1 {\n [\"CITEREFChu1978\"] = 1,\n [\"CITEREFChuAllenFoster1978\"] = 1,\n [\"CITEREFEskeldsonKellumWhiteman1993\"] = 1,\n [\"CITEREFFergusonDickstein1978\"] = 1,\n [\"CITEREFHenzler2010\"] = 3,\n [\"CITEREFKalisz2004\"] = 1,\n [\"CITEREFKaliszPawlowskiPelka1987\"] = 1,\n [\"CITEREFKaliszPawlowskiPelka1994\"] = 1,\n [\"CITEREFKris_Ardis2019\"] = 1,\n [\"CITEREFPelkaKaliszSzplet1997\"] = 1,\n [\"CITEREFReeser1969\"] = 1,\n [\"CITEREFRushOldfield1986\"] = 1,\n [\"CITEREFSasakiJensen1980\"] = 1,\n [\"CITEREFYu._ArtyukhV._Bespal\u0026#039;koE._Boole\"] = 1,\n [\"none\"] = 6,\n}\ntemplate_list = table#1 {\n [\"Citation\"] = 15,\n [\"Citation needed\"] = 2,\n [\"Cite book\"] = 3,\n [\"Cite conference\"] = 3,\n [\"Cite patent\"] = 6,\n [\"Cite tech report\"] = 5,\n [\"Cite web\"] = 2,\n [\"DEFAULTSORT:Time To Digital Converter\"] = 1,\n [\"Electrical and electronic measuring equipment\"] = 1,\n [\"Harvnb\"] = 5,\n [\"Main\"] = 1,\n [\"More citations needed\"] = 1,\n [\"More footnotes needed\"] = 1,\n [\"Multiple issues\"] = 1,\n [\"Reflist\"] = 1,\n}\narticle_whitelist = table#1 {\n}\n"},"cachereport":{"origin":"mw-web.codfw.main-6b7f745dd4-rchhd","timestamp":"20241125140833","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Time-to-digital converter","url":"https:\/\/en.wikipedia.org\/wiki\/Time-to-digital_converter","sameAs":"http:\/\/www.wikidata.org\/entity\/Q2434524","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q2434524","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2004-06-10T23:39:37Z","dateModified":"2024-03-18T04:32:55Z","headline":"device in signal processing"}</script> </body> </html>