Isolation and signal transfer
The CNY17F1300W provides 5300Vrms galvanic isolation between a DC input LED and a single phototransistor output — enough to separate low-voltage control logic from a 400VAC motor drive bus or a medical patient-contact circuit. Current transfer ratio is guaranteed between 40% and 80% at a forward current of 10mA, so the output transistor can reliably sink the rated 50mA with the LED driven at that level.
Housed in a 6-DIP (0.300-inch, 7.62mm) through-hole package — the standard optocoupler footprint that fits a 0.100-inch pitch breadboard or production PCB without a layout change.