Triac-output optoisolator for mains switching
The MOC3052SR2VM is a 1-channel triac-output optoisolator from onsemi, rated for 600 V off-state voltage and 4170 Vrms isolation. It is housed in a 6-SMD Gull Wing package for surface-mount assembly. With no zero-crossing circuit, this part supports phase-angle control — useful for resistive lamp dimming, soft-start motor drives, or heater regulation where the triac fires at any point in the AC cycle. The 1 kV/µs minimum static dV/dt rating means the output triac resists false turn-on from fast voltage transients, a common failure mode when switching inductive loads like contactors or solenoids on a 240 VAC line.
Parametric fit: trigger current, hold current, and forward voltage
The LED trigger current (Ift) is 10 mA max, and the typical hold current (Ih) is 220 µA — the input LED needs at least 10 mA to latch the triac, and once latched the output stays on until the load current drops below 220 µA near the AC zero-cross. Forward voltage (Vf) is 1.18 V typical at the LED, and the DC forward current limit is 60 mA — the input side can be driven directly from a 3.3 V or 5 V logic output with a series resistor, staying within the 60 mA absolute maximum.
Active lifecycle and sourcing reality
New designs can proceed without near-term obsolescence risk.
Industrial temperature range and approvals
The part carries UR and VDE agency approvals for safety compliance.