This part is a kind of Photocoupler called PC817, PC817A.
Function of this product has High Density Mounting Type Photocoupler.
Package : DIP 4 Pin Type
Manufacturers : Sharp Electrionic Components
Image and pinout :
Some of the text within the PDF file :
The PC817 is an optocoupler, also known as an optoisolator. It is a device that combines a light-emitting diode (LED) and a phototransistor or photodetector in a single package. The purpose of an optocoupler is to electrically isolate two circuits while allowing them to communicate with each other optically.
The PC817 optocoupler specifically has an LED emitter and a phototransistor detector. When current is applied to the LED, it emits light that activates the phototransistor, allowing current to flow through it. This enables the transfer of electrical signals or data from one circuit to another without direct electrical connection.
Isolating high-voltage and low-voltage circuits: It can be used to provide electrical isolation between circuits operating at different voltage levels, protecting sensitive components from potential voltage spikes or noise.
Signal transmission: It can transmit signals across isolation barriers, such as in industrial automation, where it can be used to transfer signals from a microcontroller to high-power devices, such as relays or motors.
Noise suppression: It can help reduce noise or interference by isolating circuits, especially in situations where ground loops or electromagnetic interference may be a concern.
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PC817 PDF Datasheet Download