Adaptive feedthrough cancellation in MEMS gyroscopes in reconfigurable IC+FPGA platform

Abstract

In this work, we explored a programmable compensation capacitance methodology to mitigate the effects of feedthrough current and offset in two widely used detection architectures in a newly developed concentrated spring MEMS gyroscope: differential drive-sense and electromechanical amplitude modulation architecture. This study is based on a recently launched commercial MEMS development platform, AS3125-SDK, which contains a multichannel high-performance reconfigurable IC front-end and a high speed FPGA with micro controllers that allows for implementation of calibration and control of MEMS inertial sensors. We used programmable arrayed trimming capacitors to remove feedthrough and increase the dynamic range of the amplifiers by 30dB in the direct differential. The same technique demonstrated a 10dB improvement in the sense channel and reduce the offset in the drive channel for the electromechanical amplitude modulation architecture.