Design and Implementation of Low Temperature Drift Suppression for Micro-Machined Gyroscope

Micro machined gyroscope is an important inertial sensor, which has the advantages of high integration, small size and low power consumption. However, due to the temperature sensitivity of silicon and electronic devices, the bias and scale factor of micro machined gyroscopes have temperature drift, which limits their engineering applications, the frequency mismatch between the driving mode and the detecting mode of the micro-machined gyroscope is caused by the process error of the micro-machined gyroscope, which not only deteriorates the mechanical sensitivity of the gyroscope, moreover, the frequency mismatch between the driving mode and the detection mode results in the quadrature error of the driving coupling of the gyro detection mode. Based on this, firstly, the relationship between the bias factor and scale factor of MEMS gyroscope and its dynamic and electrical parameters is analyzed. Secondly, a self-calibration capacitance detection scheme based on triangular electrode is proposed, and the temperature effect of the scheme is analyzed. Finally, the effectiveness of the proposed scheme is verified by experiments. The experimental results show that, in the driving mode, when the temperature range is from −10 °C to 60 C, the scale factor temperature coefficient of the gyroscope is reduced from −8845 ppm/°C to 1660 PPM/°C, and the bias temperature coefficient is reduced from −0.97°/s/°C to −0.42°/s/°C, the scheme effectively reduces the temperature sensitivity of gyro bias and scale factor.