5300Vrms isolation — where it fits in the BOM
The VO617A-7X016 is a Vishay single-channel phototransistor optocoupler in a 4-DIP through-hole package (0.400" lead spacing). Its 5300Vrms isolation rating puts it in the class for industrial-grade galvanic barriers — think motor-drive feedback, off-line PSU secondary sensing, and PLC digital input isolation.
CTR 80-160% at 5mA — predictable gain without over-drive
Current transfer ratio is specified min 80%, max 160% at If=5mA — a tighter window than many general-purpose optocouplers. That means the designer can set the LED current and count on the output transistor saturating without adding margin for wide CTR spread. The 400mV Vce saturation ceiling at 50mA output confirms the transistor pulls low enough for 5V or 3.3V logic. Rise and fall times are both 2µs typical; turn-on is 3µs, turn-off 2.3µs. That is fast enough for 100kHz PWM loops or serial data isolation at moderate rates.
Vishay lists the VO617A-7X016 as Active.
Temperature range and handling
The DC input type means it expects a forward current, not an AC waveform; for AC line sensing you would add an external diode bridge.