What 5000Vrms isolation and 600V off-state mean for your mains load
The FOD420SDV is a single-channel Triac-output optoisolator from onsemi rated for 5000Vrms isolation and 600 V off-state blocking voltage. That isolation rating lets it bridge a SELV control circuit directly to a 240 VAC line without a separate relay — the creepage distance inside the 6-SMD Gull Wing package supports the safety barrier. The 600 V off-state means it can switch inductive loads like small motors or solenoids where the commutation spike can exceed the line peak.
Why 10kV/µs dV/dt and 60µs turn-on matter in a noisy panel
The static dV/dt minimum of 10kV/µs is the key spec for industrial environments — without it, fast transients from adjacent contactors or VFDs can false-trigger the Triac output. The 60µs turn-on time is intentionally slow; it filters high-frequency noise on the LED trigger line and prevents the output from conducting on sub-cycle spikes. This part has no zero-crossing circuit, so you get full phase-angle control when driving resistive loads like heaters or incandescent lamps.
Active production and certification coverage
onsemi lists the FOD420SDV as Active with ROHS3 compliance — no end-of-life risk for current BOMs. The part carries cUL, FIMKO, UL, and VDE approvals, which streamlines equipment certification for North American and European markets. The operating temperature range of -55°C to 100°C covers outdoor telecom cabinets, industrial enclosures, and cold-storage environments.
Package and sourcing note
Supplied in Tape & Reel or Cut Tape, surface-mount 6-SMD Gull Wing. The 6-SMD package footprint is shared with other onsemi optotriacs in the same family — if you are cross-shopping, the key parametric deltas are trigger current and dV/dt rating. Sourced per RFQ; current pricing confirmed at quote time.