Triac output and random-phase switching
The onsemi MOC3053M is a single-channel optoisolator with a Triac output, rated for 600 V off-state voltage and 4170 Vrms isolation. It has no zero-crossing circuit, so the output triggers on any phase of the AC waveform — useful for phase-angle control or random-turn-on applications like soft starters or lamp dimmers where the triac fires immediately on the LED trigger.
Trigger sensitivity and noise immunity
The minimum static dV/dt is 1 kV/µs — this figure governs immunity to false turn-on from fast voltage transients on the AC line; a lower dV/dt rating would risk the triac latching on from a surge or motor commutation spike. Hold current (Ih) is 540 µA typical — once triggered, the triac stays latched until the load current drops below this level near the AC zero crossing. The forward voltage drop across the LED is 1.18 V typical at 60 mA max forward current, so the input side dissipates under 70 mW at full drive.
Package and temperature range
UL approved and RoHS3 compliant per onsemi's current lifecycle status.
