4170Vrms isolation for industrial signal isolation
The CNY172M is a single-channel optoisolator from onsemi, built for galvanic isolation between a DC input and a transistor-with-base output. Its 4170Vrms isolation rating covers the 250V working voltage common in motor-drive feedback, PLC digital inputs, and AC-mains-referenced sensor interfaces. The current transfer ratio spans 63% to 125% at 10mA forward current, giving enough gain headroom to drive a 5V logic input or a low-power relay coil without an external transistor stage.
Through-hole DIP with transistor-base output
Housed in a 6-DIP (0.300", 7.62mm) through-hole package, the CNY172M mates with standard 0.100-inch pitch sockets or wave-solder pads. The base pin on the output side allows the designer to add a base resistor or a speed-up capacitor for switching applications. Typical turn-on and turn-off times are 2µs and 3µs respectively, with rise/fall times of 4µs and 3.5µs — fast enough for 10–20 kHz PWM isolation or serial data at moderate baud rates. The output transistor can sink up to 50mA continuous at a maximum Vce of 70V, with a saturation voltage of 400mV typical — adequate for driving a 24V PLC input module or a 5V CMOS gate.
Active lifecycle with industrial temperature range
ROHS3 compliance is confirmed, so the part meets current EU and global restriction-of-hazardous-substances requirements for new designs.
