Multiplexed analog control system for electrostatic actuator array

摘要

A multiplexed analog control system for an micro electromechanical systems (MEMS) array of electrostatic actuators, such as tiltable mirrors in an optical switch. Each actuator includes a variable gap capacitor formed as part of the movable mechanical element. A hold capacitor is connected to each actuator capacitor, and a selectable high-voltage inverter connects them to provide a bipolar drive signal of 50% duty cycle. A single power digital controlled current source is connected to all the drive circuits to provide a high-power correction signal. Address decoders enable a selected one of the drive circuits to add or subtract the correction from the hold capacitor.