Research and experiment on the drive frequency control of the MEMS gyroscope

In order to realize the precise control for the drive frequency of the micro electromechanical system (MEMS) gyroscope, a frequency control scheme based on phase locked loop (PLL) was proposed in the article. The working principle of the MEMS gyroscope was analyzed which pointed out the importance of the drive frequency. The frequency control process with PLL was deduced which showed that the drive frequency can strictly trace the inherent frequency of the MEMS gyroscope. Based on the analysis, the circuit was designed and an experiment was done. The result indicates that the frequency is able to follow the inherent frequency in time and the control precision is 0.62 ppm, which is 0.09% of the self-excited drive control scheme. Therefore, the frequency control scheme is feasible and reliable.