Optocoupler for isolated signal transfer
The Vishay SFH617A-2X006 is a single-channel phototransistor optocoupler in a 4-DIP through-hole package, designed for galvanic isolation between a DC input and a transistor output. Its 5300Vrms isolation rating suits it for power-supply feedback, motor-drive interface, and industrial sensor isolation where safety isolation is required. The part is in the 63% to 125% current transfer ratio (CTR) bin at 10mA forward current, giving a consistent gain window for logic-level coupling.
Ratings that drive the BOM decision
The 5300Vrms isolation voltage is the headline spec — it defines the safety margin for reinforced insulation in mains-connected circuits. The CTR range of 63% to 125% at 10mA means the output transistor saturates reliably with a standard 10mA LED drive, but you need to check the minimum CTR at your actual forward current if running below 10mA. Output transistor can handle up to 70V and 50mA continuous, covering 5V and 24V logic and relay drive. The 400mV Vce saturation at 10mA keeps power dissipation low in the output stage.
The 4-DIP through-hole package is a rework tech's friend: easy to hand-solder or desolder with a basic iron, no hot-air profile needed. Tube shipping means parts arrive aligned and undamaged, but if your pick-and-place line expects tape, you'll need to transfer to a feeder-compatible carrier.