Non-polarized contactless relay

Abstract

Disclosed is a non-polarized, contactless relay constructed of electronic circuitry devoid of mechanical contacts but capable of performing the same function as a relay with such contacts. The relay includes a transformer, a control circuit for applying an oscillatory signal to the primary windings of the transformer in accordance with a command input, a rectifying circuit for rectifying A.C. power obtained from the secondary windings of the transformer in response to the oscillatory signal applied to the primary windings, a smoothing circuit which smooths the rectified output produced by the rectifying circuit for delivering D.C. power, and switching means composed of a pair of MOS-type field-effect transistors driven by the D.C. output of the smoothing circuit. The command input, namely '1' or '0' logic, applied to the control circuit results in the supply of the D.C. signal to the MOSFETs when logical '1' holds, driving the MOSFETs into conduction to form a closed path between the output terminals of the switching means and, hence, close the relay.