Lesson 01
Optocoupler
animation
Interactive Electronics Trainer
Optocoupler - Interactive Simulation
An optocoupler, or opto-isolator, converts the input-side electrical signal into light and transfers that light to an isolated output side. The input and output circuits stay electrically separated.
Selected Type
Phototransistor
LED Current
11.5mA
Output Current
9.2mA
Status
ON
Controls
Input Signal
Realtime Logic
Conventional current on the input side flows through the LED from positive to negative. The light crosses the isolation barrier and triggers the output device. Phototransistor and photodiode types drive a DC loop, while PhotoTRIAC is suited to AC load control.
Isolation Rating: 2500 V
Effective Transfer: 80%
Self tests: passed
Phototransistor Visualizer
Input LED to light beam to isolated Phototransistor output circuit.
ACTIVE
What is Optocoupler?
An optocoupler combines an LED and a light-sensitive output device in one isolation component. It transfers a signal without directly electrically connecting the input and output circuits.
Phototransistor Type
This type is widely used for digital isolation, microcontroller I/O isolation, and relay driver feedback because it offers simple, reliable DC switching behavior.
Photodiode Type
Photodiode optocouplers are useful when faster response is needed. They are a better fit for high-speed signal transfer than standard phototransistor designs.
PhotoTRIAC Type
PhotoTRIAC optocouplers are used for AC load control, solid-state relay behavior, and mains TRIAC triggering applications.