An optocoupler moves signals between two circuits using light instead of electricity. That way, the input and output stay electrically separate; there is no direct connection, just light doing the job. In this guide, you'll learn how they work and how you can use one in your own projects. It uses light to do the job, which helps keep things safe. What is an Optocoupler? Optocouplers are integrated electronic components. An optocoupler consists of a Transmitter as an IR LED and a Receiver as a photosensitive component. when light is emitted by an LED and that light hits the photosensor (Photodiode, Phototransistor, PhotoTriac) then the photosensor starts to flow the current.
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