{"title":"A New Approach to Design Low Power Continues-Time Sigma-Delta Modulators","authors":"E. Farshidi","volume":28,"journal":"International Journal of Electrical and Computer Engineering","pagesStart":825,"pagesEnd":832,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/10914","abstract":"<p>This paper presents the design of a low power&nbsp;second-order continuous-time sigma-delta modulator for low power<br \/>\r\napplications. The loop filter of this modulator has been implemented&nbsp;based on the nonlinear transconductance-capacitor (Gm-C) by&nbsp;employing current-mode technique. The nonlinear transconductance&nbsp;uses floating gate MOS (FG-MOS) transistors that operate in weak&nbsp;inversion region. The proposed modulator features low power&nbsp;consumption (&lt;80uW), low supply voltage (1V) and 62dB dynamic&nbsp;range. Simulation results by HSPICE confirm that it is very suitable&nbsp;for low power biomedical instrumentation designs.<\/p>\r\n","references":"[1] C. A. D. E. La Croz-Blas, A. J. Lopez-Martin and A. Carlosena, \"1.2V\r\n5uw class-AB CMOS log-domain integrator with multi decade\r\ntuning,\" IEEE. Trans. Circuits Syst. II, Analog Digit. Signal process.\r\nvol. 52, no.10, pp. 665-668, Oct. 2005.\r\n[2] D. Payton and C .Enz, \"A micro power class-AB CMOS Log-domain\r\nfilter for DECT applications,\" IEEE J. solid-State Circuits, vol. 36,\r\nno. 7, pp. 1067-1075, Jul. 2001.\r\n[3] E. Farshidi, \"A Micropower Current-Mode Sigma-Delta Modulator\r\nfor Biomedical Applications,\" Presented in the 17th IEEE Signal\r\nProcess. and Communications Application Conference, SIU-09, pp.\r\n856-859, Antalya, Turkey, April 2009.\r\n[4] O. Shoaei and W. M. 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