A low-noise high-linearity interface ASIC for MEMS gyroscopes

This paper presents a continuous-time analog interface ASIC for use in MEMS gyroscopes.A charge sensitive amplifier with a chopper stabilization method is adopted to suppress the low-frequency noise.In order to cancel the effect caused by the gyroscope capacitive mismatch,a mismatch auto-compensation circuit is implemented.The gain and phase shift of the drive closed loop is controlled separately by an auto gain controller and an adjustable phase shifter.The chip is fabricated in a 0.35 m CMOS process.The test of the chip is performed with a vibratory gyroscope,and the measurement shows that the noise floor is 0.003/s/pHz,and the measured drift stability is 43/h.Within –300 to 300/s of rotation rate input range,the non-linearity is less than 0.1%.