Package and rework reality
The FOD2741BSD: This is an 8-SMD Gull Wing package (8-SMD supplier device package) — the leads fan out flat, so you can inspect every joint visually and touch up a cold solder with a standard iron. No hidden balls, no underfill. The 5000Vrms isolation rating means the mould compound is thick; it holds heat longer under hot air, so let the preheat soak a few extra seconds before you lift the part, or you risk pad delamination.
What the CTR range means for your drive margin
The current transfer ratio is guaranteed 100% minimum to 200% maximum at 10 mA forward current. That spread tells you the LED-to-phototransistor gain can vary by 2:1 across reels. If your design relies on the output saturating at a specific load current, you need to bias the input LED so the weakest unit (100% CTR) still drives the output into the 400 mV Vce saturation ceiling. The 50 mA absolute output per channel gives you headroom for driving a logic gate input or a small relay coil.
Temperature grade and deployment
That covers most factory-floor PLC I/O modules, motor-drive feedback isolation, and HVAC controller boards. The 5000Vrms isolation is enough for reinforced insulation in mains-voltage applications per IEC 60950-1, so this part fits where you need to separate a 24 VDC control side from a 230 VAC power stage.
Active lifecycle — sourcing posture
Listed as Active by onsemi (product status current). The base product number is FOD2741, so any PCN or die revision will carry that prefix.