CAPACITIVE CHARGE BASED SELF-SENSING AND POSITION OBSERVER FOR ELECTROSTATIC MEMS MIRRORS

摘要

An oscillator system includes an electrostatic oscillator structure configured to oscillate about an axis based on a displacement that varies over time; an actuator configured to drive the electrostatic oscillator structure about the axis, the actuator having a first capacitive element with a first capacitance that is dependent on the displacement and a second capacitive element with a second capacitance that is dependent on the displacement is, includes; a sensing circuit configured to receive a first displacement current from the first capacitive element and a second displacement current from the second capacitive element, integrate the first displacement current to generate a first capacitive charge value, and integrate the second displacement current to generate a second capacitive charge value; and a measurement circuit configured to receive the first and second capacitive charge values and to measure the displacement of the electrostatic oscillator structure based on the first and second capacitive charge values.