The CNY171TVM is a single-channel optoisolator from onsemi with a 4170Vrms isolation rating. The output is a phototransistor with a separate base pin, which lets you bias the base for faster switching or connect a base-emitter resistor to kill leakage at high temperature. The collector can swing up to 70 V and sink 50 mA continuous — enough to drive a logic gate input, a relay coil with a series resistor, or a small DC load directly. Current transfer ratio (CTR) runs from 40% to 80% at 10 mA forward current.
Switching speed and temperature range
Turn-on time is 2 µs typical, turn-off 3 µs typical, with rise and fall times of 4 µs and 3.5 µs maximum. That puts the usable switching frequency around 50–100 kHz for a 50% duty cycle signal — fast enough for isolated gate drive at moderate frequency or for passing a PWM feedback signal across the isolation barrier.
Package and mounting – through-hole DIP
The CNY171TVM comes in a 6-DIP package with 0.400-inch (10.16 mm) body width. The input is DC only — no AC input rectifier built in. If you need to isolate an AC signal, add an external diode bridge or use a dedicated AC-input optoisolator.