A module containing an optocoupler is commonly called an optocoupler module or an opto-isolated module, and in power applications, it may be referred to as a solid-state relay (SSR) module.

Overview

A module with an optocoupler integrates an optical isolator to transfer electrical signals between two electrically isolated circuits using light, typically from an LED to a photodetector such as a phototransistor, photodiode, or triac . This isolation protects sensitive low-voltage circuits from high-voltage spikes, electrical noise, or surges .

Common Types

• Optocoupler Module / Opto-Isolated Module: A general-purpose module that uses an optocoupler to isolate input and output signals, often used in microcontroller circuits, sensor interfaces, and communication lines .
• Solid-State Relay (SSR) Module: A specialized module where the optocoupler drives a power switch (like MOSFETs or triacs) to control high-voltage AC or DC loads while maintaining electrical isolation .
• Phototransistor Optocoupler Module: Uses a phototransistor as the output device, suitable for digital signal isolation and low-to-medium current switching .

Applications

• Microcontroller Protection: Prevents voltage spikes from damaging sensitive inputs and outputs.
• Power Electronics: Isolates control circuits from high-voltage AC or DC loads.
• Sensor Circuits: Reduces noise interference from processing circuits to sensor readings.
• Communication Interfaces: Provides galvanic isolation in data transmission lines. In summary, a module with an optocoupler is generally called an optocoupler module or opto-isolated module, and when used to switch power, it is often referred to as a solid-state relay module. These modules leverage optical coupling to safely transfer signals while maintaining electrical isolation between circuits .