Single-channel phototransistor coupler with 3750 Vrms barrier
The VOS615A-1X001T is a single-channel phototransistor optocoupler from Vishay's VOS615A series. It provides 3750 Vrms galvanic isolation between input and output, with a transistor output rated to 80 V and 50 mA continuous.
CTR range and aging margin
Current transfer ratio is specified at 40% minimum and 80% maximum, both measured at a forward current of 10 mA. The 40% floor leaves room for LED aging over the product lifetime — a common failure mode in isolated feedback loops where CTR drift can push a regulator out of regulation. Designing with the minimum CTR rather than the typical value ensures the circuit still switches correctly years into service.
Rise and fall times are 3 µs and 4 µs typical, with turn-on and turn-off times both 5 µs.
Housed in a 4-pin SOIC package (4.40 mm width, 0.173" body) with a 4-SSOP supplier device package designation. Surface-mount assembly compatible with standard reflow profiles.