Load control circuit including automatic AC/DC discernment

摘要

A control circuit for switching AC or DC loads and for automatically discerning the presence of an AC or a DC power supply via a switch has been provided. The control circuit is coupled to alternately render a switch operative and non-operative wherein the switch is coupled across a load which is powered up by either an AC or a DC power supply. The control circuit includes an AC/DC discernment circuit for ascertaining whether the load is powered up by an AC or a DC power supply. The control circuit also includes circuitry for comparing signals sensed by the switch with predetermined thresholds (which are a function of whether an AC or DC determination has been made) for providing logic signals to control the operation of the switch.