The Disign of CMOS Integrated Acceleration Detection Circuit System

In this dissertation, we designed a kind of CMOS integrated precision acceleration detection system which is use high performance operation amplifier as the core. It was analysis directly as a low noise accelerometer and the principle of charge amplification. Detection circuit is based on the principle of time detection, which can be detected variation of the acceleration continuously in a successive time, and improving the detection accuracy. The input terminal of the circuit using sensitive charge amplifier to realize C-V conversion, which is effectively avoid the switch noise of detection principle. The whole circuit is designed and simulated based on 0.5μm CMOS process. The research result of Operational Amplifier module has shown that, the circuit’s the DC open-loop gain is 85.96dB, and its phase margin is 62.8°, and the effect input noise is 3.632 Hz nV / . The research result of overall current has shown that, full scale range of the closed-loop system between ±2.5 V the voltage is ±30V. The detection sensitivity is 16.2mV/g, which is enough to conform the requirements of the low noise accelerometer.