Voltage and pull-in time in current drive of electrostatic actuators

Abstract

The absolute maximum value of the voltage developed across an electrostatic actuator when driven by a current source has been calculated as well as an absolute minimum for the pull-in time. These two results are calculated for a drive using a /spl delta/-pulse of current and numerical assessment is given to show that for a nonzero parasitic capacitance, a realistic shape of the current pulse, or a finite value of the damping coefficient do not increase the maximum value of the voltage developed beyond that limit and that the pull-in time is always larger than the analytical minimum. A scaled-up macromodel of an electrostatic actuator has been used to register voltage transients to validate the theoretical predictions.