onsemi has marked the CNY172FVM as Obsolete. The tube packaging and date-code consistency are verified before shipment.
Rated at 4170Vrms isolation, this optocoupler provides galvanic separation between primary and secondary circuits in applications like motor-drive feedback, PLC digital inputs, and isolated DC-DC converter loops — the 4.17 kV rating covers reinforced insulation per IEC 60950-1 for 230 VAC mains environments. The current transfer ratio (CTR) is specified as 63% minimum and 125% maximum at a forward current of 10 mA — a tight bin that guarantees consistent LED drive current across production lots, so the downstream logic sees a predictable collector current without over-driving the LED. Switching speeds of 4 µs rise, 3.5 µs fall (max) and 2 µs turn-on, 3 µs turn-off (typ) limit the usable data rate to roughly 50-100 kbps in typical isolated serial links — adequate for 115.2 kbps UART or low-speed I²C, but not for CAN or high-speed SPI.
Housed in a 6-SMD Gull Wing package (6-SMD per the supplier device code), the CNY172FVM sits on a standard SOIC-6 footprint with 1.27 mm pitch — reflow compatible with lead-free profiles up to 260°C peak. The tube packaging means parts are shipped in anti-static tubes, not tape-and-reel, so pick-and-place feeders may require tube-to-tape conversion. Operating temperature range -40°C to 100°C covers industrial enclosures and outdoor telecom cabinets — the 100°C upper limit is below the 125°C automotive grade, so avoid under-hood or engine-bay deployment without derating the LED current.
Output ratings and drive limits
Maximum forward current of 60 mA and typical forward voltage of 1.35 V set the LED drive budget — a 5 V supply with a 365 Ω series resistor delivers the 10 mA test condition and keeps the LED within its safe operating area across temperature. Vce saturation is 400 mV max at the rated collector current — this low saturation voltage ensures the output can pull a logic input low to within 0.4 V of ground, meeting TTL and LVCMOS thresholds without an external level shifter.