Design and analysis of a two-stage OTA for sensor interface circuit

Abstract

This paper discusses the design of an operational transconductance amplifier (OTA) circuit foruse in a capacitive sensor interface circuit. The OTA converts a differential voltage input into the current as part of a switched capacitor integrator module. In this paper, a two-stage OTA is proposed which has high gain, high output swing and low noise. The circuit was implemented using 0.13μm Silterra CMOS technology and simulated using the Mentor Graphic Design Architect software package. The results show that the OTA is able to achieve 74dB gain and 20KHz bandwidth when operated using a 2.5V power supply, with a total power consumption of 1.3mW.