Complementary electrostatic driving apparatus for microactuator with parasitic capacitances offset

摘要

An electrostatic driving apparatus for a microactuator is provided, in which a parasitic capacitance is offset to improve the performance thereof. According to the complementary electrostatic driving apparatus for the microactuator, in order to prevent an excitation signal from being mixed with a sensing signal via the parasitic path formed of parasitic capacitance according to the structure of the microactuator and vibration characteristics thereof, which cause noise, signals having opposite polarities are applied to activating vibration plates using an inverter such that the activating vibration signals of each plate, which cause noise, are offset, thereby markedly improving the signal-to-noise ratio. Also, the vibration displacement can be easily detected by a circuit which is not integrated with an actuator. In addition, a sensing unit is simplified, reducing the initial costs. Further, when the excitation signals are applied at the both sides of the vibration direction of the suspended vibration plate, only the AC component, i.e., the component, of the electrostatic force acts, so that the resonant characteristics can be improved without an offset of the displacement.