A 1.1 V very low-power /spl Sigma//spl Delta/ modulator for 14-b 16 kHz A/D conversion using a novel class AB transconductance amplifier

This paper presents a second order /spl Sigma//spl Delta/ modulator implementation for a supply voltage of 1.1 V. A new fully differential CMOS class AB transconductance amplifier has been designed in order to achieve high-resolution under very-low-voltage and very-low-power operation. The modulator has been implemented using the AMS/spl I.bar/CDS 0.35 /spl mu/m CMOS technology and postlayout simulations have been performed showing 14 bits of resolution with an oversampling ratio of 160 and less than 40 /spl mu/W of quiescent power consumption. To the author's knowledge no other /spl Sigma//spl Delta/ modulator has been reported with such a low quiescent consumption that achieves similar dynamic range and signal bandwidth.

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