Integrated micromachined accurate electrostatic true rms-to-dc converter

Abstract

The rms value gives the average energy content of a signal, which is an important parameter in measurements of electrical signals. For non-sinusoidal signals of arbitrary shape a true rms converter should be used. From the existing converters, like electronic, thermal, electrodynamic and electrostatic types, only electronic and thermal converters have been monolithically integrated to date. With the development of micromachining techniques it is possible to integrate also the electrostatic converter. Merging this micromachined converter with on-chip readout electronics enables an accurate converter to be realised when placed in a feedback loop.<>