Design and test on the drive circuit of micro-machined gyroscope

The micro-machined gyroscope, with advantages of small size, lower weight, high reliability, lower power consumption and lower cost, has an observably increasing usage in many fields. In order to verify the designed performance parameters of capacitive micro-machined gyroscope, the open-loop drive circuit is designed and tested. In the laboratory condition, because the open-loop drive circuit has the advantages of simpler design, easier regulation, and without interference of the others signal and noise, the open-loop drive circuit can be used to drive up the micro-machined gyroscope. However, when the natural frequency of micro gyroscope changes for some reasons, the output signal offset will appear and the measurement accuracy will decrease. Therefore, the open-loop drive circuit is only in laboratory. While in practice, the closed-loop drive circuit which can automatic tracking the natural frequency of drive mode should be used to make sure highly linear output signal.