A low-noise interface for MEMS vibration gyroscope based on a novel power-efficient C/V conversion structure

A low-noise MEMS vibration gyroscope interface is presented in this paper. A novel capacitance to voltage (C/V) conversion structure is introduced, which consists of a fully differential capacitor bridge and an active filtering net. An auto-calibration method is proposed, which can compensate the gyroscope mismatch to less than 2fF. We use a multistage noise shaping (mash) sigma-delta modulator to convert the analog signal to bit stream. The input referred noise of C/V conversion stage is 0.63 aF/√Hz at 8 kHz in simulation. The chip converts sensor output into bit stream with 106dB dynamic range.