A CMOS digitally programmable class AB OTA circuit

A new low voltage digitally programmable operational transconductance amplifier (OTA) circuit is presented. The circuit utilizes a novel class AB buffer to provide a nonslew rate-limited performance with low stand-by power consumption. The transconductance of the OTA can be digitally programmed over a wide range independently of the stand-by power. The OTA can be programmed to achieve a constant settling time for different load capacitors. Experimental results from a 1.2 /spl mu/m chip are presented.