A high performance quartz vibrating gyroscope interface circuit driven by square-wave

Abstract

A new simple interface circuit for quartz vibrating gyroscope (QVG) driven by square-wave is presented in this paper. The interface circuit is composed of self-excited loop of driving circuit and detecting circuit. Temperature compensation, low noise and low coupling design are adopted in the circuit to achieve the targets of rapid oscillation start, high stability on all-temperature range and linearity. The interface circuit is fabricated in a 0.5 µm CMOS process and the test results show that the scale factor is 19.94 mV/°/s with an input angular ratio range of ±200°/s. The angular random walk and bias drift are 0.095°/√hr and 2.5°/hr respectively. The non-linearity can reach to 97 ppm and the zero drift and P-P value are 20°/hr and 80°/hr at the temperature from −45 °C to 85 °C. Meanwhile, the short stability at room temperature in one hour is 8.86°/hr (1-sigma) and the start time is less than 1 s. This design realizes a high standard with a simple structure.