| MEMS gyroscope can measure rotation rates, which can be used in navigation and image stabilization with its small size, less power consumption and low cost advantages in consumer products. In order to improve the scale factor for the input rate, closed-loop drive on the drive axis resonant frequency, mode-matched operation on the sense axis are discussed and adapted in this research. Besides, quadrature null control is also engaged to reduce long term error for the improvement of bias instability.;With all these works, we present a 2 mm diameter, 35 mum thick disk resonator gyro (DRG) fabricated in silicon with integrated 0.35 mum CMOS analog front-end circuits. The device is fabricated in the commercial InvenSense Fabrication MEMS-CMOS integrated platform and it allows this DRG to achieve Brownian noise-limited performance. The angle random walk (ARW) is measured to be 0.008 (°/s)/√Hz and the bias instability is 20 °/hr.;For gaining wider bandwidth with lower Q design and smaller size feature to saving die area, 1mm DRG which is also fabricated in InvenSense NF process is introduced later. Because it has lower Brownian noise compared with the previous version, an improved low noise unit-gain buffer fabricated in TSMC 0.18 mum CMOS process is adapted to achieve the ARW in 0.012 (°/s)/√Hz and the bias instability is 18 °/hr. |
