Research On Performance Optimization Of MEMS Gyro Combined With Electric Feedthrough Suppression And Temperature Compensation

With the development of Micro-Electro-Mechanical System(MEMS)technology,MEMS gyroscope has become an inertial sensor widely used in civil,commercial,and military applications.Due to the non-ideal factors in the MEMS gyroscope material and processing technology and circuit,the effective performance of the gyroscope is greatly reduced.Among them,the crosstalk of the driving signal to the sensitive detection end-the electric feedthrough interference,the external temperature change and other factors have a great influence on the performance of the gyroscope.In the control detection circuit of the MEMS gyroscope,there is electrical feedthrough noise between the driving modal input signal and the sensitive modal output signal,which affects the gyroscope zero rate output,and is one of the important error sources.Since the raw material silicon of the MEMS gyroscope is a heat sensitive material,the temperature change causes the related physical properties of the gyroscope,such as the system stiffness,to change,thereby changing the resonant frequency and quality factor of the gyroscope,resulting in the scale factor and zero bias output of the gyroscope.Variety.Therefore,suppressing the MEMS gyroscope electric feedthrough interference and temperature compensation of the gyroscope is of great significance for improving the performance of the gyroscope.The main work done in this paper is as follows:(1)For the problem that the driving signal generates electrical feedthrough to the sensitive detecting end,the parameter excitation method is used to suppress the MEMS gyroscope electric feedthrough interference.By adding a parameter excitation signal whose frequency is twice the driving excitation signal,the driving mode is excited together with the driving excitation signal,and the driving excitation amplitude is reduced while maintaining the amplitude of the output signal,thereby reducing the electric feedthrough.(2)Aiming at the problem that temperature variation affects the gyroscope zero-bias performance,the relationship between temperature and performance parameters such as gyroscope frequency and quality factor is analyzed and constructed.The self-sensing technology is used to compensate the gyroscope’s scale factor and zero offset to improve the sensitivity of the scale factor and zero bias to temperatureThe experimental results show that using the parametric excitation method to drive the gyroscope can reduce the gyroscope electrical feedthrough signal amplitude from 141.25mV to 38.75mV.First-order temperature compensation is applied to the zero offset in the range of 30℃~65℃.The zero-bias stability is reduced from 187.32°/h to 19.16°/h.The fourth-order temperature compensation is applied to the zero-bias in the range of 65℃~90℃.The zero-bias stability is reduced from 1871.41°/h to 31.81°/h.The results show that the parameter excitation method can effectively reduce the electrical feedthrough interference,and the temperature compensation can greatly reduce the temperature sensitivity of the zero offset and improve the performance of the MEMS gyroscope.