Low-Power and High-Precision Readout Circuit Design for Micro-Electromechanical Systems (MEMS) Acceleration Sensors

Abstract

MEMS acceleration sensors are widely used in Internet of Things, electronic machinery, aerospace and other fields with outstanding advantages such as small size, high reliability, intelligence and high integration. Traditional MEMS acceleration sensors limit their applications due to high-power consumption and low-precision; the standby time and service life are being increased in order to study the low-power and high-precision MEMS acceleration sensor readout, this paper adopts the Fully Differential Switched Capacitor-Variable Gain Amplifier (FDSC-VGA) instead of the traditional high-power Capacitance-to-Voltage Converter (CVC-VGA), Sample-and-Hold Circuit (S&H) and Anti-Aliasing Filter (AAF) as front-end modules. At the same time, a high-precision four-phase non-crossover clock is designed to precisely control the timing switch, thus effectively reducing the power consumption of the MEMS acceleration sensor readout circuit; then, the overall readout circuit is simulated and verified by Dong Bu HiTek 0.18 μm process. The results show that the error rate of the output voltage of FDSC-VGA is reduced from 8.03% to 0.88% compared with the conventional readout circuit, and the noise power consumption of MEMS acceleration sensor readout circuit can be reduced by 65%.