Galvanic isolation with 5300 Vrms rating
The VO618A-2X017T is a single-channel phototransistor optocoupler from Vishay, providing 5300 Vrms of galvanic isolation between input and output. This isolation level suits industrial applications where safety isolation is required between a low-voltage control side and a higher-voltage power or sensor side — think PLC digital inputs, motor drive feedback, or isolated DC-DC converter feedback loops. The DC input side drives an infrared LED with a typical forward voltage of 1.1 V; the output is a phototransistor rated for up to 80 V and 50 mA continuous. The 4.2 µs turn-on and 23 µs turn-off times are adequate for 10-100 kHz switching signals, though the 3 µs rise and 14 µs fall times should be checked against your edge-rate budget in high-speed isolated communication links.
CTR range and drive margin
The current transfer ratio spans 63% to 125% at a forward current of 1 mA. At minimum CTR, a 1 mA LED drive yields 0.63 mA at the phototransistor collector — enough to saturate a 10 kΩ pull-up at 5 V, but marginal for a 1 kΩ load. Design the collector resistor and output logic threshold around the 63% floor, not the 125% ceiling, to guarantee switching across temperature and LED ageing. The 400 mV maximum Vce saturation at the output ensures low on-state voltage drop when the phototransistor is fully turned on, keeping power dissipation in the output stage manageable even at 50 mA load current.
Active production — no obsolescence concern
For BOM planning, this means the part is available for new designs and ongoing production without forced redesign risk in the near term. The -55°C to 110°C operating temperature range covers industrial and outdoor equipment without the need for a commercial-grade variant.
Package and footprint for assembly
The 4-SMD Gull Wing package (4-SMD) is a standard optocoupler footprint with 2.54 mm pin pitch. The gull-wing leads provide good solder joint inspection access and are compatible with reflow soldering profiles typical for lead-free assemblies. No exposed pad or thermal management is required — the package dissipates through the leads and board copper.