Parametric drive MEMS resonator with closed-loop vibration control at ambient pressure

This paper reports a MEMS resonator with closed-loop vibration control which can be parametric driven at ambient pressure. Non-interdigitated comb fingers are used as parametric force electrodes and optimized design enables the electrodes to generate large electrostatic stiffness, which makes parametric drive possibly realized at ambient pressure and low Q-factor (65.8). Closed-loop vibration control by using parametric drive is realized in a digital electronics system. Star-up process of the resonator validates the control method, with the start-up time less than 0.2s and the amplitude standard deviation 0.04mV (300ppm). The proposed parametric drive closed-loop control method can be used in MEMS resonant sensors at low vacuum or ambient pressure, therefore reducing the packaging cost and power consumption by decreasing the drive voltage.