# A Power-Efficient CMOS Adaptive Biasing Operational Transconductance Amplifier

• Torfifard, Jafar (Faculty of Electrical Engineering, University of Technology Malaysia) ;
• A'ain, Abu Khari Bin (Faculty of Electrical Engineering, University of Technology Malaysia)
• Accepted : 2012.08.27
• Published : 2013.04.01

#### Abstract

This paper presents a two-stage power-efficient class-AB operational transconductance amplifier (OTA) based on an adaptive biasing circuit suited to low-power dissipation and low-voltage operation. The OTA shows significant improvements in driving capability and power dissipation owing to the novel adaptive biasing circuit. The OTA dissipates only $0.4{\mu}W$ from a supply voltage of ${\pm}0.6V$ and exhibits excellent high driving, which results in a slew rate improvement of more than 250 times that of the conventional class-AB amplifier. The design is fabricated using $0.18-{\mu}m$ CMOS technology.

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