A closed-loop system with DC sensing method for vibratory gyroscopes
The paper presents a closed-loop system scheme with DC sensing method for vibratory gyroscopes. A DC sensing method is employed to convert the amplitude-modulated capacitive signal to voltage. The system realizes a closed-loop control in the driving mode. A high voltage (HV) drive signal which is compatible with the gyro is obtained by the on-chip level shifter. The ASIC occupies 2.5×2.0mm2 in a 0.35μm BCD process. The system requires a differential supply of ±12V and can work under a resonant frequency from 3 to 10 kHz.