A highly linear wide range continuous tuning CMOS OTA

This paper introduces a new operational transconductance amplifier (OTA) that maintains a highly linear wide continuous tuning range and wide frequency response range, enabled by splitting linear voltage-to-current conversion and tuning into two different blocks. The input differential pair assures a wide input voltage swing via a fixed bias current, and a programmable-gain current amplifier working in saturation region can assure over three decades Gm tuning range and 119 MHz bandwidth. With plusmn1.5 V supply voltages, HSPICE simulation results using TSMC 0.35-mum CMOS process model confirm the expected good performance of the proposed OTA.