The device is also known as opto-isolator since no current is involved between the two chips, rather only light signals, and also because the IR emitter and IR detector feature a 100% electrically insulation and isolation. Unlike transformers or capacitors, which can only transfer AC signals across the isolation barrier, optocouplers can. Optocouplers, also known as opto-isolators, are components that transfer electrical signals between two isolated circuits by using infrared light. In this guide, you'll learn how they work and how you can use one in your own projects. Optocouplers are very useful when you need to isolate different sections of a circuit, for example in power. I am going to need to use an optocoupler to isolate two circuits in two situations. A light source is a LED while the detector or sensor is a phototransistor.
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