The LH1510 is a SPST normally open switch (1 Form A) that can replace electromechanical relays in many applications. The relay is constructed using a GaAlAs LED for actuation control and an integrated monolithic die for the switch output. The die, fabricated in a highvoltage dielectrically isolated technology, is comprised of a photodiode array, switch control circuity, and MOSFET switches. In addition, the relay employs current-limiting circuity enabling it to pass FCC 68.302 and other regulatory voltage surge requirements when overvoltage protection is provided. The LH1510 is the only relay in the family that provides current limiting for unidirectional dc applications.