What is 4N28 Optocoupler : Pin Configuration & Its Working

• An Optocoupler is an electronic component that interconnects two separate electrical circuits utilizing a light-sensitive optical interface.
• The transformer provides Isolation between the primary input voltage and secondary output voltage.
• we can provide electrical isolation between an input source and an output load by using an Optocoupler.
• The 4N25 family is an industry-standard single channel phototransistor coupler.
• This family includes the 4N25, 4N26, 4N27, and 4N28.
• Each optocoupler consists of gallium, arsenide, infrared LED, and a silicon NPN phototransistor.

Features of 4N28 Optocoupler

• Isolation test voltage 5000 VRMS
• Interfaces with common logic families
• Input-output coupling capacitance < 0.5 pF
• Industry standard dual-in-line 6-pin packaging

Pin Configuration

1. Anode
2. Cathode
3. No Connection
4. Emitter
5. Base
6. Collector

Applications of 4N28 Optocoupler

• Circuit Isolation
• DC motor speed control
• PWM applications
• AC mains detection
• Reed relay driving
• Switch-mode power supply feedback
• Telephone ring detection
• Logic ground isolation