BD682S

Overview

The BD682S is a PNP Darlington transistor manufactured by onsemi, housed in a TO-126-3 package. It is designed for high-current switching applications with a maximum collector current of 4A and a collector-emitter voltage rating of 100V. The device integrates two transistors to provide high current gain, making it suitable for driving loads that require significant base drive current reduction.

Feature Summary

• High current output capability up to 4A
• Integrated Darlington configuration for enhanced current gain
• Robust 100V voltage rating for industrial environments

Applications

• Industrial motor control circuits
• Power supply load switching
• Relay driver stages

Procurement Notes

Verify the specific datasheet revision and manufacturing origin when sourcing the BD682S, as historical Fairchild assets were acquired by onsemi. Ensure the component matches the TO-126-3 physical footprint and pinout requirements of your design. Cross-reference part markings against official manufacturer documentation to confirm authenticity and avoid counterfeit risks during procurement.

Selection Notes

Select the BD682S when high current gain is required without excessive base drive current. Consider its thermal performance within the TO-126-3 package for continuous operation. Evaluate the saturation voltage characteristics against system efficiency targets. Compare alternative Darlington configurations if lower leakage or faster switching speeds are critical for the specific application constraints.

Part Context

This component belongs to the bipolar junction transistor (BJT) category, specifically utilizing a Darlington pair topology. It represents a legacy product line originally developed by Fairchild Semiconductor, now maintained under the onsemi portfolio. The device serves as a discrete solution for power switching tasks where integrated circuit complexity is unnecessary.

Replacement Considerations

Check for direct equivalents such as the BD681 series variants or other PNP Darlington transistors with matching 4A/100V ratings. Verify pin compatibility and thermal resistance specifications before substituting.