The onsemi 4N263S is a single-channel optoisolator in a 6-SMD gull-wing package, designed for surface-mount assembly. It accepts a DC input and provides a transistor-with-base output, making it suitable for logic-level signal isolation and switching applications where the base terminal allows external biasing or speed-up networks. Key isolation and transfer ratings: 5300Vrms isolation voltage, a minimum current transfer ratio of 20% at 10mA forward current, and typical turn-on/turn-off times of 2µs each. The output transistor can handle up to 30V collector-emitter with a saturation voltage of 500mV max. The forward voltage is typically 1.18V, and the maximum DC forward current is 100mA.
Lifecycle and sourcing posture
The 4N263S is marked as Obsolete by onsemi. For designs still requiring this package and pinout, qualification of a functionally equivalent optoisolator from the same family or an alternate vendor should be considered to mitigate single-source risk.