0.5‐V bulk‐driven differential amplifier

Abstract

SUMMARY A new 0.5‐V fully differential amplifier is proposed in this article. The structure incorporates a differential bulk‐driven voltage follower with conventional gate‐driven amplification stages. The bulk‐driven voltage follower presents differential gain equal to unity while suppressing the input common‐mode voltage. The amplifier operates at a supply voltage of less than 0.5 V, performing input transconductance almost equal to a gate transconductance and relatively high voltage gain without the need for gain boosting. The circuit was designed and simulated using a standard 0.18‐µm CMOS n‐well process. The low‐frequency gain of the amplifier was 56 dB, the unity gain bandwidth was approximately 3.2 MHz, the spot noise was 100 nV/√Hz at 100 kHz and the current consumption was 90 μΑ. Copyright © 2012 John Wiley & Sons, Ltd.

A 0.5 V bulk‐driven voltage follower/DC level shifter and its application in class AB output stage

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Bulk linearized CMOS differential pair transconductor for continuous-time OTA-C filter design

“…There are many papers describing gate driven [7][8][9][10][11][12][13] and bulk driven MOS pairs [14][15][16][17][18][19][20][21]. A simple gate driven MOS pair unfortunately has poor linearity of voltage to current conversion, therefore the other voltage to current converters are often used when the linearity is important [7].…”

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Design and implementation of sub 0.5‐V OTAs in 0.18‐μm CMOS

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