Active production — 4170Vrms isolation in a 6-SMD Gull Wing
The CNY17F1SR2VM is an active-production optoisolator from onsemi, delivering 4170Vrms of galvanic isolation between a DC input LED and a phototransistor output.
The Current Transfer Ratio is specified at 40% minimum and 80% maximum at a forward current of 10 mA. This bin width means the design must tolerate the low end: at 40% CTR, the output transistor needs at least 4 mA of base drive to saturate, which sets the minimum LED current. The typical turn-on time of 2 µs and turn-off time of 3 µs, with rise/fall times of 4 µs and 3.5 µs respectively, are fast enough for 100 kHz switching signals but not for high-speed data — this is a logic-level or slow-signal isolator, not a digital isolator replacement.
Output ratings and sourcing posture
The output transistor is rated for 70 V maximum and 50 mA continuous current, with a Vce saturation of 400 mV maximum.