How a PhotoMOS Solid State Relay Works

PhotoMOS An Introduction to PhotoMOS Relays

A relay is an electrical component whose output is controlled in an open or closed position by applying or removing drive voltage from an electrically isolated circuit.   For many years electromechanical relays were the only choice to perform such a function.  During the last two decades, however, new technologies have emerged enabling semiconductors to switch output circuits with an electrical control signal via electronic, magnetic, optical or other means that require no mechanical movement.

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