低噪声硅微陀螺敏感电容电荷读出电路设计

摘要

硅微陀螺敏感电容电荷读出电路性能的优劣直接决定着陀螺仪测量精度.通过对敏感电容读出电路的建模分析,采用差分调制技术实现了低噪声信号输出,从电路组成、参数设置、PCB布局布线等多方面综合考虑,优化设计了能抑制低频噪声以及高灵敏度电荷读出电路.实验结果表明:该电路输出噪声为-116.24 dBV/√Hz,敏感电容检测分辨率可达1.16 ×10-19 F√Hz.%Measurement precision of silicon micro-gyroscope is determined by sensitive capacitor readout circuit.Through modeling analysis on sensive capacitor readout circuit,use differential modulation technology to realize low noise signal output.A charge readout circuit which can suppress low frequency noise and high sensitivity is optimally designed in parameter and PCB.Esperimnental results indicate that output noise of the circuit is -116.24 dBV/√Hz and sensitive capacitor detecting resolution is 1.16 × 10-19F/√Hz.