The MOC3061, MOC3062 and MOC3063 devices consist of gallium arsenide infrared emitting diodes optically coupled to monolithic silicon detectors performing the functions of Zero Voltage Crossing bilateral triac drivers. They are designed for use with a triac in the interface of logic systems to equipment powered from 115/240 Vac lines, such as solidstate relays, industrial controls, motors, solenoids and consumer appliances, etc.