From Light to Signal: How Optocouplers Safeguard Electronic Systems

Do Subscribe us ‪@UATechnicalSolutions‬
1: Optocouplers work based on the principle of using light to transmit signals and achieve electrical isolation between two circuits. The basic structure of an optocoupler includes a light-emitting diode (LED) on the input side and a photodetector (such as a photodiode, phototransistor, or photometric) on the output side, housed in the same package but physically separated by a transparent barrier.
2: The light emitted by the LED crosses the isolation barrier and reaches the photodetector on the output side. The photodetector converts the received light signal back into an electrical signal. The electrical signal obtained from the photodetector is an isolated replica of the input signal on the LED side. The output signal is electrically separated from the input signal, providing galvanic isolation between the two circuits.
3: Here is an example of a wired circuit using a optocoupler to separate the two different voltage circuits without any current or voltage interference in-between input and output circuits. As shown a 5 volt signal is used to power up the optocoupler and on the output a 12 volt lamp with a battery is connected to power the lamp. Since the two circuits are totally separated any voltage spike or surge on any of the two circuits can not cause any damages to the other circuit.