4N28TVM

Overview

The 4N28TVM is a transistor output optocoupler manufactured by onsemi. It features an infrared emitting diode optically coupled to an NPN silicon phototransistor with a base lead for sensitivity control. The device provides electrical isolation with a rated isolation voltage of 4170 Vrms. It is housed in a standard 6-pin DIP package designed for through-hole mounting, suitable for general-purpose signal isolation applications.

Feature Summary

• Integrated base terminal on the phototransistor allows for adjustable gain and switching speed optimization
• High isolation voltage rating ensures reliable separation between input and output circuits
• Standard 6-pin dual inline package facilitates easy integration into printed circuit boards

Applications

• General-purpose signal isolation in industrial control systems
• Interface circuits for microprocessors and logic systems
• Switching power supply feedback loops

Procurement Notes

Verify the specific suffix 'TVM' against the manufacturer's current datasheet to confirm packaging details and compliance status. Ensure the component matches the required isolation voltage and current transfer ratio specifications for the target design. Cross-reference the manufacturer code with authorized distribution channels to guarantee authenticity and traceability.

Selection Notes

Select this component when a cost-effective solution with base access is required for optimizing response time or gain. Consider the DIP-6 footprint constraints and through-hole assembly requirements. Evaluate the current transfer ratio and collector-emitter breakdown voltage against the load requirements of the isolated circuit.

Part Context

This part belongs to the family of transistor output optocouplers from onsemi, formerly Fairchild Semiconductor. These devices are widely used for basic galvanic isolation. The 4N28 series is a legacy part number often replaced by newer equivalents, but remains available for maintaining existing designs that rely on its specific pinout and performance characteristics.

Replacement Considerations

Check for direct pin-compatible replacements such as the 4N28M or generic equivalents like PC123 if sourcing constraints exist. Verify that any substitute maintains the same isolation voltage and CTR range to ensure circuit compatibility without redesign.