微机械电容式加速度传感器测试电路研究

在测量硅微电容式加速度传感器时,由于器件信号的微弱和寄生电容的干扰,提高加速度的稳定性和分辨率非常困难.针对这种情况,作者分析对比开关性和调制解调型两种常见微弱电容检测方法优缺点,并提出了一种微电容检测的改进电路,用此电路对电容式加速度传感器进行了测试.数据表明,微加速度计灵敏度为1.63 V/gn,可以检测到10-17F量级的电容值.

Detecting circuits for the micro accelerometer With capacitance detection

Due to the parasitic capacitance and weak output signal, which is limited by its dimensions, it is difficult to improve the resolution and stability of micro accelerometer efficiently. Two most popular methods on the measurement of tiny capacitance signal are discussed and compared, and a novel ameliorated capacitance detecting circuit is proposed. A micromachined capacitive accelerometer is developed and measured with the novel detecting approach. The resulting sensitivity is about 1.63 V/g., and a capacitance resolution of 10^-17 F can be achieved.