The MOC3073M is a random-phase triac optoisolator from onsemi, designed to drive high-voltage triacs or directly switch AC loads in industrial and appliance controls. Its 800 V off-state voltage gives headroom for 240 VAC or 480 VAC line applications, while the minimum static dV/dt of 1 kV/µs prevents false turn-on from line transients or inductive load switching — a common failure point in motor and solenoid drives.
Isolation barrier and UL recognition — safety for mains-referenced circuits
With 4170 Vrms isolation and UL agency approval, this part meets reinforced insulation requirements for separating low-voltage control logic from hazardous mains voltage. The 1.18 V typical forward voltage and 6 mA maximum LED trigger current allow direct drive from 3.3 V or 5 V logic outputs through a series resistor, keeping the BOM simple.