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Best Alternatives to FOD817A3SD

Package: 4-SMD, Gull WingonsemiPhotovoltaic OutputPackage: Tape & Reel (TR); Cut Tape (CT); Digi-Reel®Number of Channels: 1Voltage - Isolation: 5000VrmsCurrent Transfer Ratio (Min): 80% @ 5mAVoltage - Output (Max): 70V

FOD817A3SD is a popular 4-pin SMD phototransistor optocoupler. Finding a substitute requires matching the package, pinout, and Current Transfer Ratio (CTR) of 80-160%.

AI replacement insight

Electrical riskmedium

CTR differences are common and require circuit analysis.

Package risklow

Many alternatives use a compatible SOP-4/Gull Wing package.

Sourcing risklow

This is a common optocoupler type with many vendors.

Can it be replaced directly?

No direct drop-in replacement with identical key parameters was found. Alternatives require engineering review, primarily for the Current Transfer Ratio (CTR).

Best replacement path

Consider LITEON's LTV-816S series or Toshiba's TLP628M, but verify the different Current Transfer Ratio (CTR) in your design.

Main risk

The primary risk is a mismatch in the Current Transfer Ratio (CTR), which can affect loop gain, switching speed, and overall circuit stability.

Recommended alternatives

1
LTV-816S-TA1-D package
LTV-816S-TA1-D

LITEON

Needs validationmedium risk

A functional alternative in a similar SMD package with higher VCEO but a significantly different CTR.

View details

Alternative comparison matrix

Feature / factorFOD817A3SDTLP628M(TP5,ELTV-816S-TA1-DAlt 3Compatibility / risk
Package4-SMD, Gull Wing4-SMD, Gull Wing4-pin SOP4-SMD, Gull Wing / 4-pin SOP — Package is a direct match.; LTV-816S-TA1-D: Likely form-fit compatible, but requires footprint verification.
Voltage70 V300 V80 V300 V / 80 V — VCEO is significantly higher, offering a large safety margin.; LTV-816S-TA1-D: Collector-Emitter Voltage (VCEO) is higher, providing more margin.
Current80-160%50-600%300-600%50-600% / 300-600% — Very wide Current Transfer Ratio (CTR) range may cause performance variation.; LTV-816S-TA1-D: Significantly higher Current Transfer Ratio (CTR) will alter circuit gain.
Temperature-55°C to +110°C-55°C to 110°C-50°C to +110°C-55°C to 110°C / -50°C to +110°C — Operating temperature range matches.; LTV-816S-TA1-D: Slightly narrower operating range at the low end.

Application & sourcing insights

Questions & answers

LTV-816S-TA1-D is a strong functional alternative with a compatible package and higher voltage rating, but its higher CTR (300-600%) must be validated in your circuit.