Analysis and Optimization of a Diode-Bridge Based Differential Capacitance Readout Circuit for MEMS Gyroscopes

In this paper, a thorough theoretical analysis for diode-bridge based differential capacitance readout circuit was carried out. Based on the theoretical model, a numerical simulation of the relationship between the circuit parameters versus the amplitude-frequency and phase-frequency responses of the readout circuit was presented. According to the simulation results, a readout circuit parameters optimization method was demonstrated. The experimental results show that the effect of circuit parameters on the output was basically consistent with the numerical simulation. The optimized gain of the readout circuit is about 117.1mV/fF.