A high speed and high linearity OTA in 1-V power supply voltage

Abstract

This paper proposes a high performance operational transconductance amplifier (OTA) which is based on the pseudo-differential architecture with addition of linearity improved circuits. The OTA is designed under low power supply voltage consideration while its gain, excess phase, and linearity are well maintained. A common-mode control system, including common-mode feedback (CMFB) and common-mode feedforward (CMFF) circuits, is added to ensure stability at high frequency. Results show that the topology can achieve the total harmonic distortion (THD) to the -56dB with 100MHz balanced differential input signals up to 300mVpp at 1-V supply voltage by the TSMC 0.18 mu m CMOS process. Its power consumption is 1.8mW.