IC 4N35 Optocoupler

IC 4N35 Optocoupler

Product information:

With a 4N35 optocoupler you can connect two circuits without them being physically connected. In other words; you can for example switch a motor on and off from your Arduino without your Arduino being on the same circuit as the motor. This way you don't have to worry about getting strange peak voltages or currents back on your Arduino pin.

If you apply a voltage to pin 1, an internal LED will light up, which is then picked up by a light sensor through which current will flow. (Current will then flow between pins 4 and 5.)

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