Mems gyroscope: electrical method to measure the mechanical parameters and the quadrature error

A full characterization of the mechanical parameters of vibrating MEMS sensors is required before integrating the mechanical and the electronic part. This is to verify that the main design specifications, such as the resonant frequency and the damping coefficient, are fulfilled. Moreover, if we consider not just a vibrating sensor but a vibrating gyroscope, the characterization of the frequency response is not enough, it's important to ensure that the quadrature error is below a fixed threshold. This paper attempts to study both the sensor characterization and the quadrature-error through an electrical approach; in particular, the quadrature error identification is based on the measurement of the ground current originated from the time varying charge, due to the movement of the comb drive actuators. The results achieved with this method are revealed and discussed.