Galvanic isolation for industrial signal paths
The CNY17F3SR2VM is a single-channel optocoupler from onsemi that provides 4170Vrms isolation between a DC LED input and a phototransistor output. That isolation rating suits it for breaking ground loops in motor-drive feedback, PLC digital inputs, and medical-device signal isolation where patient-contact safety margins are required. Its current transfer ratio is specified at 100% minimum and 200% maximum when the LED is driven at 10 mA. This narrow CTR window means the designer can set the LED series resistor once and expect a consistent logic-level swing at the output across temperature and production lots — no re-tuning per reel.
Switching speed and output drive capability
Typical turn-on time is 2 µs and turn-off time is 3 µs, with rise and fall times of 4 µs and 3.5 µs maximum. This is fast enough for 10–50 kHz PWM feedback loops or serial data at moderate baud rates, but not for high-speed isolated communication like I²C or CAN. The output transistor can sink up to 50 mA continuous and block up to 70 V.
The surface-mount footprint matches standard 6-pin DIP Gull Wing land patterns — no special pad geometry needed.