A Parametric Fitting Method for Parasitic Capacitance in MEMS Resonators

The feedthrough effect is a key factor affecting the performance of MEMS gyroscopes, particularly in force balance modes and capacitive sensing systems, where it often causes zero rate output (ZRO) and crosstalk issues. This paper focuses on a MEMS Quad Mass Gyroscope (QMG), addressing the interference caused by parasitic feedthrough capacitance on the system's response. It derives the transfer function and frequency response model of the gyroscope and proposes a parameter fitting method based on the Levenberg-Marquardt algorithm. The fitting results show a root mean square error (RMSE) of $\mathbf{0. 0 0 0 2 2 5 1}$. The $\mathbf{Q}$ value prediction error is $\mathbf{0. 6 2 \%}$. These results accurately estimate key parameters, including parasitic feedthrough capacitance and the quality factor (Q).