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class="mw-page-title-main">Flash memory controller</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. 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src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Lexar_USB_stick_8_GB_-_Silicon_Motion_SM3253L-0309.jpg/220px-Lexar_USB_stick_8_GB_-_Silicon_Motion_SM3253L-0309.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Lexar_USB_stick_8_GB_-_Silicon_Motion_SM3253L-0309.jpg/330px-Lexar_USB_stick_8_GB_-_Silicon_Motion_SM3253L-0309.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Lexar_USB_stick_8_GB_-_Silicon_Motion_SM3253L-0309.jpg/440px-Lexar_USB_stick_8_GB_-_Silicon_Motion_SM3253L-0309.jpg 2x" data-file-width="1729" data-file-height="1729" /></a><figcaption>Lexar USB stick 8 GB - Silicon Motion SM3253L - USB 2.0 single-channel flash controller.</figcaption></figure> <p>A <b>flash memory controller</b> (or <b>flash controller</b>) manages data stored on <a href="/wiki/Flash_memory" title="Flash memory">flash memory</a> (usually <a href="/wiki/NAND_flash" class="mw-redirect" title="NAND flash">NAND flash</a>) and communicates with a <a href="/wiki/Computer" title="Computer">computer</a> or <a href="/wiki/Electronic_device" class="mw-redirect" title="Electronic device">electronic device</a>. Flash memory controllers can be designed for operating in low <a href="/wiki/Duty-cycle" class="mw-redirect" title="Duty-cycle">duty-cycle</a> environments like <a href="/wiki/Memory_card" title="Memory card">memory cards</a>, or other similar <a href="/wiki/Data_storage_device" class="mw-redirect" title="Data storage device">media</a> for use in <a href="/wiki/Personal_digital_assistant" title="Personal digital assistant">PDAs</a>, <a href="/wiki/Mobile_phone" title="Mobile phone">mobile phones</a>, etc. <a href="/wiki/USB_flash_drive" title="USB flash drive">USB flash drives</a> use flash memory controllers designed to communicate with <a href="/wiki/Personal_computer" title="Personal computer">personal computers</a> through the <a href="/wiki/USB_port" class="mw-redirect" title="USB port">USB port</a> at a low duty-cycle. Flash controllers can also be designed for higher duty-cycle environments like <a href="/wiki/Solid-state_drive" title="Solid-state drive">solid-state drives</a> (SSD) used as data storage for <a href="/wiki/Laptop" title="Laptop">laptop</a> computer systems up to <a href="/wiki/Mission-critical" class="mw-redirect" title="Mission-critical">mission-critical</a> enterprise <a href="/wiki/Storage_array" class="mw-redirect" title="Storage array">storage arrays</a>.<sup id="cite_ref-kingston_1-0" class="reference"><a href="#cite_note-kingston-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="Initial_setup">Initial setup</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flash_memory_controller&action=edit&section=1" title="Edit section: Initial setup"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>After a flash storage device is initially manufactured, the flash controller is first used to format the flash memory. This ensures the device is operating properly, it maps out bad flash memory cells, and it allocates spare cells to be substituted for future failed cells. Some part of the spare cells is also used to hold the <a href="/wiki/Firmware" title="Firmware">firmware</a> which operates the controller and other special features for a particular storage device. A directory structure is created to allow the controller to convert requests for logical sectors into the physical locations on the actual flash memory chips.<sup id="cite_ref-kingston_1-1" class="reference"><a href="#cite_note-kingston-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Reading,_writing,_and_erasing"><span id="Reading.2C_writing.2C_and_erasing"></span>Reading, writing, and erasing</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flash_memory_controller&action=edit&section=2" title="Edit section: Reading, writing, and erasing"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <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/Flash_memory#Principles_of_operation" title="Flash memory">Flash memory § Principles of operation</a></div> <p>When the system or device needs to read data from or write data to the flash memory, it will communicate with the flash memory controller. Simpler devices like SD cards and USB flash drives typically have a small number of flash memory die connected simultaneously. Operations are limited to the speed of the individual flash memory die. In contrast, a high-performance solid-state drive will have more dies organized with parallel communication paths to enable speeds many times greater than that of a single flash die.<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. (August 2010)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="Wear-leveling_and_block_picking">Wear-leveling and block picking</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flash_memory_controller&action=edit&section=3" title="Edit section: Wear-leveling and block picking"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Wear_leveling" title="Wear leveling">Wear leveling</a></div> <p>Flash memory can withstand a limited number of program-erase cycles. If a particular flash memory block were programmed and erased repeatedly without writing to any other blocks, the one block would wear out before all the other blocks thereby prematurely ending the life of the storage device. For this reason flash controllers use a technique called <a href="/wiki/Wear_leveling" title="Wear leveling">wear leveling</a> to distribute writes as evenly as possible across all the flash blocks in the SSD. In a perfect scenario this would enable every block to be written to its maximum life so they all fail at the same time.<sup id="cite_ref-Li-Pin_Chang_2-0" class="reference"><a href="#cite_note-Li-Pin_Chang-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Flash_translation_layer_(FTL)_and_mapping"><span id="Flash_translation_layer_.28FTL.29_and_mapping"></span>Flash translation layer (FTL) and mapping</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flash_memory_controller&action=edit&section=4" title="Edit section: Flash translation layer (FTL) and mapping"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Flash_file_system" title="Flash file system">Flash file system</a></div> <p>Usually, flash memory controllers also include the "flash translation layer" (FTL), a layer below the file system that maps host side or file system logical block addresses (LBAs) to the physical address of the flash memory (logical-to-physical mapping). The LBAs refer to sector numbers and to a mapping unit of 512 bytes. All LBAs that represent the logical size visible to and managed by the file system are mapped to a physical location (block ID, page ID and sector ID) of the Flash. As part of the <a href="/wiki/Wear_leveling" title="Wear leveling">wear leveling</a> and other flash management algorithms (bad block management, read disturb management, safe flash handling etc.), the physical location of an LBA might dynamically change frequently. The mapping units of an FTL can differ so that LBAs are mapped block-, page- or even sub-page-based. Depending on the usage pattern, a finer mapping granularity can significantly reduce the flash wear out and maximize the endurance of a flash based storage media.<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><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><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> The deduplication function to eliminate redundant data and duplicate writes is also added in FTL.<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> </p><p>As the FTL metadata takes up its own flash space, it needs protection in case of power loss. In addition, it is possible for the mapping table to wear out before other parts of the flash memory has, prematurely ending the life of a storage device. This is usually avoided in enterprise devices by allocating an oversized space for spares, although more durable forms of storage like <a href="/wiki/Magnetoresistive_RAM" title="Magnetoresistive RAM">MRAM</a> has been proposed for FTL too.<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. (May 2023)">citation needed</span></a></i>]</sup> </p><p>The FTL may has three types: page mapping, block mapping and hybrid mapping. Page mapping can has higher performance, but it has bigger FTL metadata size and higher cost, and its usually used on <a href="/wiki/Solid_state_drive" class="mw-redirect" title="Solid state drive">solid state drives</a>. Block mapping can has smaller metadata size and lower cost, but it has lower performance, and its usually used on <a href="/wiki/USB_flash_drive" title="USB flash drive">USB flash drives</a>. On page mapping FTL implementations, the ratio of FTL metadata size and storage capacity is usually 1:1000, for example, a 1TB flash storage device may has 1GB of FTL metadata. </p> <div class="mw-heading mw-heading2"><h2 id="Garbage_collection">Garbage collection</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flash_memory_controller&action=edit&section=5" title="Edit section: Garbage collection"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Garbage_collection_(SSD)" class="mw-redirect" title="Garbage collection (SSD)">Garbage collection (SSD)</a></div> <p>Once every block of a solid-state storage device has been written one time, the flash controller will need to return to some of the initial blocks which no longer have current data (also called stale blocks). The data in these blocks were replaced with newly written blocks and now they are waiting to be erased so that new data can be written into them. This is a process called <i><a href="/wiki/Garbage_collection_(computer_science)" title="Garbage collection (computer science)">garbage collection</a></i> (GC). All SSDs, CF Cards, and other flash storage devices will include some level of garbage collection. The speed at which a flash controller will do this can vary.<sup id="cite_ref-OCZ_WA_7-0" class="reference"><a href="#cite_note-OCZ_WA-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <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=Flash_memory_controller&action=edit&section=6" 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"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-kingston-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-kingston_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-kingston_1-1"><sup><i><b>b</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 class="citation web cs1"><a rel="nofollow" class="external text" href="http://media.kingston.com/pdfs/FlashMemGuide.pdf">"Flash Memory Guide"</a> <span class="cs1-format">(PDF)</span>. kingston.com<span class="reference-accessdate">. Retrieved <span class="nowrap">7 March</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Flash+Memory+Guide&rft.pub=kingston.com&rft_id=http%3A%2F%2Fmedia.kingston.com%2Fpdfs%2FFlashMemGuide.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlash+memory+controller" class="Z3988"></span></span> </li> <li id="cite_note-Li-Pin_Chang-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-Li-Pin_Chang_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChang,_Li-Pin2007" class="citation citeseerx cs1">Chang, Li-Pin (2007-03-11). 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Archived from <a rel="nofollow" class="external text" href="http://files.iccmedia.com/magazines/basfeb15/basfeb15-p25.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2015-06-23<span class="reference-accessdate">. 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title="Multi-level cell">SLC/MLC</a></li> <li><a class="mw-selflink selflink">Flash memory controller</a></li> <li><a href="/wiki/Garbage_collection_(SSD)" class="mw-redirect" title="Garbage collection (SSD)">Garbage collection</a></li> <li><a href="/wiki/IOPS" title="IOPS">IOPS</a></li> <li><a href="/wiki/Bit_rate" title="Bit rate">MB/s</a></li> <li><a href="/wiki/Flash_memory#Memory_wear" title="Flash memory">Memory wear</a></li> <li><a href="/wiki/Open-channel_SSD" title="Open-channel SSD">Open-channel SSD</a></li> <li><a href="/wiki/Write_amplification#Over-provisioning" title="Write amplification">Over-provisioning</a></li> <li><a href="/wiki/Flash_memory#Read_disturb" title="Flash memory">Read disturb</a></li> <li><a href="/wiki/Write_amplification#Secure_erase" title="Write amplification">Secure erase</a></li> <li><a href="/wiki/Solid-state_storage" title="Solid-state storage">Solid-state storage</a></li> <li><a href="/wiki/Trim_(computing)" title="Trim (computing)">Trim command</a></li> <li><a href="/wiki/Wear_leveling" title="Wear leveling">Wear leveling</a></li> <li><a href="/wiki/Write_amplification" title="Write amplification">Write amplification</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Flash manufacturers</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Micron_Technology" title="Micron Technology">Micron</a></li> <li><a href="/wiki/Samsung_Electronics" title="Samsung Electronics">Samsung</a></li> <li><a href="/wiki/SK_Hynix" title="SK Hynix">SK Hynix</a> <ul><li>Bought <a href="/wiki/Intel" title="Intel">Intel</a>'s NAND flash SSD business and renamed it Solidigm</li></ul></li> <li>Flash Forward (joint venture between <a href="/wiki/Western_Digital" title="Western Digital">Western Digital</a> and <a href="/wiki/Kioxia" title="Kioxia">Kioxia</a>)</li> <li><a href="/wiki/Yangtze_Memory_Technologies" title="Yangtze Memory Technologies">YMTC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_flash_memory_controller_manufacturers" title="List of flash memory controller manufacturers">Controllers</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Captive</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Western_Digital" title="Western Digital">Western Digital</a> <ul><li><a href="/wiki/SanDisk" title="SanDisk">SanDisk</a></li> <li><a href="/wiki/Fusion-io" title="Fusion-io">Fusion-io</a></li> <li><a href="/wiki/HGST" title="HGST">HGST</a></li> <li><a href="/wiki/STec" title="STec">sTec</a></li></ul></li> <li><a href="/wiki/Kioxia" title="Kioxia">Kioxia</a> <ul><li><a href="/wiki/OCZ" title="OCZ">OCZ</a> (bankrupt, assets sold to Toshiba, which later spun off its SSD and flash business to Kioxia)</li> <li><a href="/wiki/Indilinx" title="Indilinx">Indilinx</a> (bought by OCZ)</li></ul></li> <li><a href="/wiki/Micron_Technology" title="Micron Technology">Micron</a></li> <li><a href="/wiki/Samsung_Electronics" title="Samsung Electronics">Samsung</a></li> <li><a href="/wiki/Seagate_Technology" title="Seagate Technology">Seagate</a> <ul><li><a href="/wiki/SandForce" title="SandForce">SandForce</a></li></ul></li> <li><a href="/wiki/SK_Hynix" title="SK Hynix">SK Hynix</a> <ul><li>Bought <a href="/wiki/Intel" title="Intel">Intel</a>'s NAND flash SSD business including controllers and renamed it Solidigm</li></ul></li> <li><a href="/w/index.php?title=FADU&action=edit&redlink=1" class="new" title="FADU (page does not exist)">FADU</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Independent</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Greenliant_Systems" title="Greenliant Systems">Greenliant Systems</a></li> <li><a href="/w/index.php?title=Goke_Microelectronics&action=edit&redlink=1" class="new" title="Goke Microelectronics (page does not exist)">Goke</a></li> <li><a href="/wiki/JMicron" title="JMicron">Maxiotek</a></li> <li><a href="/wiki/Marvell_Technology_Group" class="mw-redirect" title="Marvell Technology Group">Marvell</a></li> <li><a href="/wiki/Phison" title="Phison">Phison</a></li> <li><a href="/wiki/PMC-Sierra" title="PMC-Sierra">PMC-Sierra</a></li> <li><a href="/wiki/Silicon_Motion" title="Silicon Motion">SMI</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">SSD manufacturers</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_solid-state_drive_manufacturers" title="List of solid-state drive manufacturers">List of solid-state drive manufacturers</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Interfaces</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Advanced_Host_Controller_Interface" title="Advanced Host Controller Interface">Advanced Host Controller Interface</a> (AHCI)</li> <li><a href="/wiki/Fibre_Channel" title="Fibre Channel">Fibre Channel</a> (FC)</li> <li><a href="/wiki/NVM_Express" title="NVM Express">NVM Express</a> (NVMe)</li> <li><a href="/wiki/PCI_Express" title="PCI Express">PCI Express</a> (PCIe)</li> <li><a href="/wiki/SATA_Express" title="SATA Express">SATA Express</a></li> <li><a href="/wiki/Serial_ATA" class="mw-redirect" title="Serial ATA">Serial ATA</a> (SATA)</li> <li><a href="/wiki/Serial_attached_SCSI" class="mw-redirect" title="Serial attached SCSI">Serial attached SCSI</a> (SAS)</li> <li><a href="/wiki/USB" title="USB">Universal Serial Bus</a> (USB)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Configurations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hard_disk_drive#Form_factors" title="Hard disk drive">HDD form factors</a></li> <li><a href="/wiki/MSATA" class="mw-redirect" title="MSATA">mSATA</a></li> <li><a href="/wiki/M.2" title="M.2">M.2</a></li> <li><a href="/wiki/PCI_Express" title="PCI Express">PCI Express</a> <a href="/wiki/Expansion_card" title="Expansion card">expansion card</a></li> <li><a href="/wiki/Thunderbolt_(interface)" title="Thunderbolt (interface)">Thunderbolt</a> <ul><li><a href="/wiki/USB-C" title="USB-C">USB Type-C</a></li></ul></li> <li><a href="/wiki/U.2" title="U.2">U.2</a></li> <li><a href="/wiki/U.3" class="mw-redirect" title="U.3">U.3</a></li> <li><a href="/wiki/EDSFF" class="mw-redirect" title="EDSFF">EDSFF</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related organizations</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/International_Committee_for_Information_Technology_Standards" title="International Committee for Information Technology Standards">INCITS</a></li> <li><a href="/wiki/JEDEC" title="JEDEC">JEDEC / JC-42, JC-64.8</a></li> <li><a href="/wiki/Open_NAND_Flash_Interface_Working_Group" title="Open NAND Flash Interface Working Group">ONFI</a></li> <li><a href="/wiki/NVM_Express#History" title="NVM Express">NVMHCI Work Group</a></li> <li><a href="/wiki/USB_Implementers_Forum" title="USB Implementers Forum">USB-IF</a></li> <li><a href="/wiki/Serial_ATA_International_Organization" title="Serial ATA International Organization">SATA-IO</a></li> <li><a href="/wiki/Small_Form_Factor_Committee" title="Small Form Factor Committee">SFF Committee</a></li> <li><a href="/wiki/Storage_Networking_Industry_Association" title="Storage Networking Industry Association">SNIA</a></li> <li><a href="/wiki/Solid_state_storage_initiative" class="mw-redirect" title="Solid state storage initiative">SSSI</a></li> <li><a href="/wiki/SCSI" title="SCSI">T10/SCSI</a></li> <li><a href="/wiki/Fibre_Channel" title="Fibre Channel">T11/FC</a></li> <li><a href="/wiki/Parallel_ATA" title="Parallel ATA">T13/ATA</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" 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