Novel voltage-regulating circuit for low-voltage and low-power OTA realization using MOSFETs in the non-saturation region

An operational transconductance amplifier (OTA) is one of the most important analog building blocks. This paper proposes a novel voltage-regulating circuit for an OTA realization. The voltage-regulating circuit allows one to implement a simple structure OTA using MOSFET's in the non-saturation region. The resultant OTA using the proposed voltage-regulating circuit operates under a single 1.5 V power supply voltage. Simulation results of the OTA show harmonic distortion less than 1% even when 0.7 V/sub p-p/ input voltage is applied. Its power consumption is 85.8 /spl mu/W and cutoff frequency is 7 MHz.