Research on a Silicon Gyroscope Interface Circuit Based on Closed-Loop Controlled Drive Loop.

Qiang Li,Xiaowei Liu,Lifeng Ding,Qiang Zhang

doi:10.3390/s22030834

Abstract

The existing analysis methods for the silicon gyroscope drive loop, such as the perturbation method and period average method, cannot analyze the dynamic characteristics of the system. In this work, a linearized amplitude control model of the silicon gyroscope drive loop was established to analyze the stability and set-up time of the drive loop, and the vibration conditions of the silicon gyro were obtained. According to the above results, a new silicon gyroscope interface circuit was designed, using a 0.35 μm Bipolar-CMOS-DMOS (BCD) process, and the chip area was 4.5 mm × 4.0 mm. The application-specific integrated circuit (ASIC) of the silicon gyroscope was tested in combination with the sensitive structure with a zero stability of 1.14°/hr (Allen). The test results for the ASIC and the whole machine prove the correctness of the theoretical model, which reflects the effectiveness of the stability optimization of the closed-loop controlled drive loop of the silicon gyroscope circuit.

Highlights

IntroductionGyroscopes are sensors that can be used to detect angular velocities [1,2,3]
Amplification, phase shifting, and demodulation, the signal with the same resonant frequency of the drive mode was obtained, and the automatic gain control of this signal was realized through a peak detection module and proportional integral controller (PI) control module
The final drive signal was superimposed with the direct current (DC) reference signal, which was applied to the drive combs at the top and bottom of the left and right sides of the gyroscope structure to complete the self-excited drive of the silicon gyroscope

Summary

Introduction

Gyroscopes are sensors that can be used to detect angular velocities [1,2,3]. They are widely used in science, technology, the military, and other fields [4,5,6]. The silicon gyroscope interface circuit is required, to bring the gyroscope structure into resonance, and the angular velocity can be detected using the Coriolis force principle. In the closed-loop drive circuit of a silicon gyroscope, due to the highly non-linear component in the acceleration-to-speed signal transfer function, it was difficult to obtain an accurate analytical solution for the loop-transfer function [11,12].

Methods

Results

Conclusion