Digital Amplitude Control and Time-Division Multiplexing Detection ASIC for Horizontal DualAxis Silicon Micro-gyroscope

This paper describes a digital amplitude control and time-division multiplexing detection ASIC for horizontal dual-axis silicon micro-gyroscope. The digital drive amplitude control circuit effectively reduces the 1/f noise and improves the temperature stability of the system. At the same time, it realizes the fast and stable amplitude startup of the closed-loop drive. The time-division multiplexing detection circuit effectively reduces the power consumption and area of the dual-axis gyro-detection circuit, and improves the integration level of the system, and prevents the occurrence of signal crosstalk between two axes. Firstly, we establish an analysis model of closed-loop gyroscope drive amplitude control system, and digital PI controller is employed to realize low-noise amplitude control and fast startup. The simulation results show that the closed-loop drive amplitude setting time is 0.2s. Secondly, in the detection channel, the ADC and digital demodulation and preprocessing circuit in the detection circuit are multiplexed. The 2kHz select signal is used to complete the time-sharing output of the two outputs. The experimental results show that the angle random walk of the dual-axis silicon micro-gyroscope is $0.03^{\circ}/ h^{1/2}$.