Failure Analysis of Accelerometer Servo Circuit Caused by Electrical Damage to Differential Capacitance Detector

Servo circuit of quartz flexible accelerometer is an important signal processing unit in inertial measurement system. This paper introduced the working principle of the quartz flexible accelerometer and the composition of the servo circuit. Taking the output saturation of a quartz flexible accelerometer during the test process of inertial measurement unit as an example, according to the failure analysis process of hybrid integrated accelerometer servo circuit and the fault tree analysis based on accelerometer servo circuit fault diagnosis expert system, the fault location and failure analysis of the failed circuit are carried out, and the failure mechanism and causes are studied and analyzed. The analysis results show that the failure circuit is caused by electrical damage to the differential capacitance detector in the differential capacitance–voltage converter. In view of this problem, the prevention and improvement measures are put forward to reduce the frequency of the failure mode. Above analysis and research are of guiding significance to improve the fault analysis technology and the use reliability of servo circuit of hybrid integrated quartz flexible accelerometer.