Active production — BOM-fit for AC load switching
The onsemi FOD420 is an active-production optoisolator with a Triac output, rated for 5000Vrms isolation and 600V off-state voltage. This makes it a fit for switching AC loads like solenoids, relays, or small motors in industrial control panels, where galvanic isolation between the low-voltage logic side and the mains side is required.
Key ratings that decide the fit
The 10kV/µs minimum static dV/dt rating means the output Triac resists false turn-on from fast voltage transients on the AC line — a critical spec when driving inductive loads like contactor coils or motor starters, where line noise is common. The 60µs turn-on time is fast enough for 50/60Hz phase control but not for high-frequency PWM. The -55°C to 100°C operating temperature range covers industrial and outdoor enclosures, though the Triac's on-state voltage drop and thermal dissipation should be checked against the load current at the high end of the range.
Package and compliance for through-hole assembly
Housed in a 6-DIP (0.300", 7.62mm) through-hole package, the FOD420 mates with standard 0.100-inch pitch DIP sockets or solders directly into a PCB. The 7.62mm body width is the narrow DIP variant, so the pin spacing matches legacy layouts. Approved by cUL, FIMKO, and UL, and ROHS3 compliant — the documentation covers North American and European safety standards for isolation barriers in equipment up to 5000Vrms.