5000Vrms isolation — where this optocoupler fits
The Vishay VOL617A-1X001T is a single-channel phototransistor optocoupler with a DC input and a transistor output, rated for 5000Vrms of isolation between input and output.
The current transfer ratio is specified at 40% minimum and 80% maximum, both measured at a forward current of 5mA. This range gives the designer a known gain window for the phototransistor: at the minimum CTR, the output side still delivers enough collector current to drive a logic input or a downstream transistor with the LED driven at 5mA. The 80% ceiling prevents saturation from being too deep, which helps keep turn-off times consistent.
Output ratings and drive capability
The output transistor can handle up to 80V collector-emitter and 50mA continuous current per channel, with a maximum Vce saturation of 400mV at the rated current. That 80V ceiling is enough for 24V industrial logic rails or 48V telecom buses with margin. The 50mA output current can directly drive a small relay coil or an optocoupler input in a daisy-chain, though for higher loads an external transistor or MOSFET driver would follow.
Temperature range and environment
Rated for operation from -55°C to +110°C.
Lifecycle and compliance
It is ROHS3 compliant, meeting the latest EU restriction on hazardous substances.