A Quartz Vibrating Gyroscope Interface Circuit Driven by Sine-wave Based on Nonlinear Multiplier

Abstract

A new simple interface circuit for quartz vibrating gyroscope (QVG) driven by sine-wave is presented in this paper. The interface circuit is composed of self-excited loop of driving circuit and detecting circuit. A new multiplier is designed to achieve the controlling to drive signal. The usage of new multiplier realizes the nonlinear adjustment to the amplitude of feedback drive signal. Consequently, the requirement of rapid oscillation, low harmonic and high stability is also achieved. The interface circuit is fabricated in a 0.5μm CMOS process and the test results show that the start time of drive signal is less than 2ms. The drive signal frequency stability can reach to 0.084% (1-sigma) and the harmonic distortion is about 1.056%. The output noise of Quartz Vibrating Gyroscope is 0.00023°/s/√Hz at 3Hz and nonlinearity is about 107ppm. The bandwidth is more than 60Hz. Meanwhile, the short stability (1-sigma) is 2.1°/hr, the angular random walk (ARW) and bias drift are 0.01388°/√hr and 0.16°/hr respectively.