硅谐振压力微传感器开环测试中的信号处理技术

SIGNAL PROCESSING TECHNIQUE OF THE OPEN LOOP TESTING OF SILICON RESONANT PRESSURE MICRO SENSOR

介绍了自行设计的专用开环测试系统。该系统为一个自动测试系统，可测出谐振梁的幅频和相频特性，而且能成功地测出从拾振电阻获得的若干微伏的微弱信号。开环测试中最重要的问题是所谓的同频干扰。发现通过激励电阻与拾振电阻间的分布电容耦合的激励信号是同频干扰的最终来源。用对称激励技术成功地解决了这一问题。

The open loop testing is a necessary step in the studying of silicon resonant pressure micro sensors. The paper introduces a special open loop testing system designed by the authors. This testing system is an automatic one that can give the amplitude frequency and phase frequency properties of the resonant beam. The weak signal, about several micro volts, given by the sensing resistor can also be detected successfully by this system. As a most important problem, the so called common frequency disturbance (CFD) has been discussed. It is found that the exciting signal coupled through the distributed capacitor between the exciting resistor and the sensing resistor is the final source of CFD. A sympathetically exciting technique is used to solve this problem. It works well.