3750Vrms isolation in a 4-SOIC footprint
The VOS628A-3X001T is a Vishay 1-channel phototransistor optocoupler rated for 3750Vrms isolation. That isolation voltage suits industrial control, motor drive feedback, and AC mains sensing where galvanic separation between logic and power domains is mandatory. Input accepts both AC and DC, so it handles bipolar signals or rectified AC without an external bridge — useful in zero-cross detection or line-voltage monitoring.
CTR range and switching speed
Current transfer ratio (CTR) is guaranteed 100% minimum, 200% maximum at 1 mA forward current. This tight band means the output transistor drives a known collector current for a given LED current — no guesswork in the load resistor calculation. Turn-on time is 5 µs typical, turn-off 8 µs typical; rise/fall are 5 µs and 7 µs respectively. At 50 mA output per channel, the part handles moderate-speed digital isolation up to about 50 kHz without pulse-width distortion.
Temperature grade and package reality
The 4-SOIC package with 4.40 mm width fits standard SOIC-4 land patterns; the supplier device package is 4-SSOP. Lifecycle status is Active. Vishay continues production. Sourced per RFQ — confirm lead time and pricing against your BOM quantity at quote time.