4N25

This device is a 6-pin DIP transistor-output optoisolator with a gallium arsenide infrared emitting diode optically coupled to a monolithic silicon phototransistor detector. It is intended for medium-speed switching, general-purpose switching circuits, I/O interfacing, and coupling systems of different potentials and impedances. The input LED is rated for 60 mA continuous forward current and 3 V reverse voltage, while the output transistor is rated for 30 V collector-emitter voltage, 70 V collector-base voltage, and 150 mA continuous collector current. The isolation surge voltage is 7500 Vac peak for 1 second, and the operating temperature range is -55 °C to 100 °C.