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onsemi MOC3021SR2VM — Optoisolators

MOC3021SR2VM onsemi Optoisolator, Triac Output, 4170Vrms

MPNMOC3021SR2VM
Active

onsemi MOC3021SR2VM, 1-channel optoisolator with triac output, 4170Vrms isolation, 400 V off-state, no zero-crossing, in a 6-SMD gull-wing package, Tape & Reel / Cut Tape.

$1.0900Ref. price · indicative, final on quote
onsemi MOC3021SR2VM datasheet (PDF)
Packaging6-SMD, Gull Wing
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

MOC3021SR2VM specifications
ParameterValue
Output typeTriac
MountingSurface Mount
Voltage - isolation4170Vrms
Voltage - off state400 V
Voltage - forward (Vf)1.15V
Current - hold100µA (Typ)
Current - DC forward (If)60 mA
Current - LED trigger (Ift)15mA
Operating temperature-40°C ~ 85°C
Approval agencyIEC/EN/DIN, UL
PackageTape & Reel (TR) Cut Tape (CT)
Case6-SMD, Gull Wing
Channels1
Zero crossing circuitNo

Product details

Triac output optoisolator for AC load switching

The MOC3021SR2VM from onsemi is a single-channel optoisolator with a triac output, rated for 4170Vrms isolation and 400 V off-state voltage.

No zero-crossing means random-phase firing

The MOC3021SR2VM has no zero-crossing detection circuit. The triac fires as soon as the LED current exceeds the 15 mA max trigger threshold.

Active production, ROHS3, industrial temperature

Certification and approvals for mains-isolated designs

The part carries IEC/EN/DIN and UL approvals, certifying the 4170Vrms isolation rating.

Frequently asked questions

Can MOC3021SR2VM be used for 240V AC switching?

Yes. The 400 V off-state voltage exceeds the 340 V peak of a 240V AC sine wave, so the triac output blocks the line when off. The no-zero-crossing output means the triac turns on immediately when triggered, which is fine for resistive loads; for inductive loads like motors or transformers, add a snubber (e.g., 47 Ω + 0.01 µF) across the triac to prevent false turn-on from dV/dt.

Is MOC3021SR2VM RoHS compliant?

Yes, the MOC3021SR2VM is ROHS3 compliant, meaning it meets the EU RoHS directive with no exemptions for lead, mercury, cadmium, or other restricted substances.