4N26

Overview

The Texas Instruments 4N26 is a single-channel optocoupler featuring a gallium arsenide infrared LED coupled to an NPN silicon phototransistor. It provides electrical isolation with a maximum insulation voltage of 5000 Vrms and a minimum breakdown voltage of 30 V between collector and emitter. The device operates within a temperature range of -55 °C to +100 °C and supports a maximum forward current of 80 mA. It utilizes a standard DIP-6 package for through-hole mounting.

Feature Summary

• Provides galvanic isolation between input and output circuits using an infrared LED and phototransistor pair
• Features high insulation voltage capability for safe signal transmission across potential differences
• Includes a base lead on the phototransistor to allow for adjustable switching speed control

Applications

• General-purpose signal isolation in electronic circuits
• Switching power supply feedback loops
• Microcontroller I/O isolation

Procurement Notes

Verify component authenticity by checking manufacturer markings against official datasheet specifications. Confirm compliance status, as some variants may not meet RoHS standards. Ensure the specific suffix matches the required package and performance characteristics before procurement.

Selection Notes

Select this component when basic digital isolation is required without shutdown functionality. Consider the propagation delay and current transfer ratio limits for high-speed applications. Verify that the DIP-6 package fits the target PCB layout constraints.

Part Context

This part belongs to the family of transistor-output optoisolators designed for general industrial and commercial applications. It serves as a fundamental building block for isolating low-voltage control signals from higher-voltage loads or noisy environments.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.