Fault diagnosis of accelerometer servo circuit output saturation based on feature electrical parameters extraction

The servo circuit of quartz flexible accelerometer is an extremely vital microelectronic device in inertial system. The paper introduces the traditional analysis process about output saturation fault of accelerometer servo circuit. For the shortcomings of traditional analysis methods, a fault diagnosis method based on feature electrical parameters extraction is proposed. According to the fault phenomenon, combined with the modular characteristics of hybrid integrated circuits, the feature electrical parameters of fault modes are extracted, and the fault modes' judgment basis is set. By the judgment results of the feature electrical parameters of the fault circuit, the circuit with output saturation fault caused by the electrical damage to the differential capacitance detector and other faults can be located quickly and accurately, and it is verified by the analysis of faulty circuit samples. Targeted for these faults, the improvement measures are put forward. This analysis method improves the fault diagnosis efficiency and reliability about the accelerometer servo circuit, and has guiding significance for enhancing the success rate of the failure analysis in the hybrid integrated circuits.