Optocoupler ICs are semiconductor devices designed to couple isolated input and output circuits using light. They protect the signal receiving system by preventing high voltages. The Optocoupler features two integrated devices: a light sensor and a light emitter that functions as a simple switch. Furthermore, optocouplers generally come in semiconductor packages like PDIP or SOIC.
Alternative names for Optocouplers
Optocouplers are also known as optical couplers, optoisolators, or photocouplers.
How Do Optoisolator ICs Work?
Optocouplers are comprised of light emitters and light sensors that transfer energy from one circuit to another. The light emitter produces visible, infrared, or laser light. This emitter converts light input into a light signal detected by a light detector and converted back to an electrical signal. Optocouplers block high voltages and voltage variations and ensure the circuit and other parts are protected from propagation in the event of spikes. Thus, they are used in voltage variation applications.
Factors Necessary for the Selection of Optocouplers
Various factors determining a precise optocoupler include supply voltage, output current, switching speed, common mode noise rejection (CMR), and threshold input current IFHL/IFHL.
What is the Advantage of Using an Optocoupler?
An optocoupler's primary and significant benefit is that they are easy to bring to the circuits and perform the voltage isolation between the input circuits and output circuit blocks.
Types of Optocoupler ICs
Optocouplers from our Displays and Optoelectronics family have various types available on the electronics market:
- Photodiode
- Resistive
- Phototransistor
- Bidirectional
Output Types of Optocoupler ICs
- MOSFET
- TRIAC
- CMOS
- Darlington
- Photodarlington
- IGBT Gate Drive
- Phototransistor
- Single Transistor
- Logic Gate
Applications of Optocoupler ICs
The major function of these devices is electrical protection and they are used as either switching devices or as isolation between high and low voltage circuits. Equipment from the Display and Optoelectronics family are primarily found in devices like:
Furthermore, they are also employed in:
- Removal of electrical noise from signals
- Use small digital signals for controlling larger AC voltages.