3750Vrms isolation in a compact 4-SOIC
The Vishay VOS618A-8T is a single-channel transistor-output optocoupler designed for galvanic isolation in DC-coupled signal paths. It packs 3750Vrms of isolation into a 4-SOIC package measuring 4.40mm wide, making it a space-efficient choice for breaking ground loops or level-shifting logic signals on densely populated boards.
The current transfer ratio spans 130% to 260% at a forward current of 1mA, which means the phototransistor can sink between 1.3mA and 2.6mA of collector current with only 1mA through the LED. That range gives you predictable drive margin for TTL or CMOS inputs without overdriving the LED. The 80V output rating and 50mA per-channel current handle most logic-level and low-power load switching.
Temperature range and switching speed
Rated from -55°C to 110°C, this optocoupler suits environments where the board sees temperature extremes — think outdoor telecom, industrial motor drives, or engine-bay-adjacent electronics.
Package and mounting
Supplied in a 4-SOIC (0.173", 4.40mm width) surface-mount package, the VOS618A-8T fits standard pick-and-place assembly.