Random-phase optotriac for AC load switching
The MOC3020M is an onsemi optoisolator with a triac output rated for 4170Vrms isolation and 400 V off-state voltage — a common choice for driving medium-voltage AC loads like solenoids, fans, or resistive heaters from a low-voltage logic side. It is a random-phase (non-zero-crossing) device, meaning the output triac can be triggered at any point in the AC cycle, which suits phase-angle control applications such as incandescent dimmers or soft-start circuits. The 100 µA typical hold current gives the designer a lower bound on the load current needed to keep the triac conducting once triggered — important when switching small loads that might otherwise drop out near the zero crossing.
Package and isolation for through-hole assembly
Housed in a 6-DIP (0.300", 7.62mm) through-hole package, the MOC3020M mates with standard 0.100-inch-pitch sockets or solders directly into a PCB — no special footprint beyond the usual DIP-6 land pattern. The 4170Vrms isolation rating provides reinforced insulation between the LED input and the triac output, sufficient for line-referenced loads in appliances and industrial controls.