The CNY17F23S is a 1-channel optoisolator from onsemi with a phototransistor output, housed in a 6-SMD gull-wing package that sits flat on the board for reflow assembly. Rated for 5300 Vrms isolation, it provides basic galvanic separation between a DC input (up to 100 mA forward current) and a 70 V, 50 mA output stage. Current transfer ratio spans 63% to 125% at 10 mA forward current — the 2:1 min/max spread means the CTR bin is tight enough to avoid gain-matching issues in a multi-channel feedback loop.
Switching speed and temperature range
Typical turn-on time is 2 µs and turn-off time 3 µs, with rise and fall times of 1 µs and 2 µs respectively — adequate for 50/60 Hz mains sensing or slow digital isolation below 100 kHz.
The part is sourced to order against the BOM line — no stock-holding claim.