A multi-mode interface for MEMS vibratory gyroscope with self-tuned filter

This paper presents a multi-mode ASIC interface with self-tuned filter to support a wide variety of MEMS gyroscope with various resonance frequencies and various output signal styles of sense/drive mode. A reconfigurable readout front-end circuit is used for signal readout in the sense channel and drive loop, which can sense the capacitive, voltage and current signal output. A gyroscope-resonance-based self-tuned band-pass filter (BPF) is proposed in sense channel, whose center frequency is self-tuned to the drive resonance frequency. The method helps the ASIC to interface with a wide-range of gyroscopes with different resonance frequency without changing the BPF design. The interface is implemented in 0.35μm CMOS process. The measurement with an electromagnetic gyroscope and an electrostatic gyroscope shows the validity of the method. The electromagnetic gyroscope achieves a sensitivity of 25.2mV/°/s with a noise floor 0.02°/s/vHz and ±50°/s full scale range with 5⁰/₀₀ nonlinearity.