The feedthrough capacitance existing between the driving electrode and the monitor electrode or the detection electrode of MEMS capacitive gyroscope cause negative effects, including preventing the gyroscope from ‘electrical-mechanical’ oscillation, introducing extra feedthrough current interfering the subsequent control and measurement circuit and so on. In this paper, we propose a technique to deal with the feedthrough capacitance, which calculates and subtracts the extra feedthrough current via digital circuit implemented with FPGA.
This paper derives the critical value of the feedthrough capacitance of the gyroscope that can make ‘electrical-mechanical’ oscillation happen, and we conduct circuit simulations. We conclude that ‘electrical-mechanical’ oscillation can occur when the feedthrough capacitance is less than the critical value.
We use digital circuits to calculate feedthrough current value, and after subtracting it, we get the effective current as input to the subsequent measurement and control circuit.
We implement this method with FPGA. The circuit controls the gyroscope with the mechanical oscillation frequency of 31.1981 kHz and decreases the amplitude of the feedthrough current from 53.68 mV to an amplitude less than 2.44 mV. The experiment verifies that the method effectively cuts down the effect of the feedthrough current. Besides, this method is convenient to modify parameters and can be widely applicable.
Feedthrough Cancellation for MEMS Gyroscope Using the Calculation Method via Digital Circuit
Lect. Notes Electrical Eng.
International Conference on Autonomous Unmanned Systems ; 2021 ; Changsha, China September 24, 2021 - September 26, 2021
Proceedings of 2021 International Conference on Autonomous Unmanned Systems (ICAUS 2021) ; Chapter : 215 ; 2177-2184
2022-03-18
8 pages
Article/Chapter (Book)
Electronic Resource
English
MEMS Gyroscope Lifetime Characterization
NTRS | 2000
|Automated MEMs Gyroscope Characterization
NTRS | 2000
|Research on Stochastic Modeling of MEMS Gyroscope
Tema Archive | 2012
|