Design of High-Precision Interface ASIC for Quartz Gyroscopes with 0.022°/√hr Angle Random Walk

This work presents the design and implementation of a high-precision digital interface ASIC for quartz gyroscopes, featuring structural and circuit optimizations in the drive and detection loops to achieve a low-noise, highly integrated system. The proposed design integrates advanced analog-digital hybrid signal processing techniques, including a low-noise charge-sensitive amplifier (CSA), a fully integrated 90° phase shifter, a data converter, and a digital control and compensation circuit. These innovations effectively mitigate phase noise in the drive loop, electrical noise in the sense loop, and bias instability in the gyroscope system, enabling highly accurate detection of angular rate signals. The ASIC is fabricated using a 0.35 μm CMOS process, in conjunction with a quartz gyroscope structure, achieving an Allan variance bias instability (BI) of 0.344°/hr and an angle random walk (ARW) of 0.022°/√hr. These results highlight the integration, stability, and practicality of the digital ASIC for high-precision quartz gyroscopes, facilitating mass production and scalability for high-precision applications.