BD677AS

Overview

The BD677AS is a single NPN epitaxial silicon Darlington transistor manufactured by onsemi. It features a maximum collector-emitter voltage (VCEO) of 60 V and a maximum DC collector current of 4 A. The device has a power dissipation rating of 40 W and operates within a temperature range up to +150°C. It utilizes a TO-126-3 through-hole package with a minimum DC current gain (hFE) of 750.

Feature Summary

• High current amplification capability via Darlington configuration
• Robust thermal performance for high power dissipation applications
• Through-hole mounting for reliable mechanical connection

Applications

• High-current switching circuits
• Power amplifier stages
• Motor control interfaces

Procurement Notes

Verify component authenticity against the manufacturer's official documentation, as the part status is listed as obsolete. Confirm that the specific suffix 'AS' corresponds to the intended packaging and quality grade requirements for your design. Cross-reference the datasheet revision to ensure all electrical parameters match your system specifications before finalizing procurement plans.

Selection Notes

Select this component when high current gain and moderate voltage handling are required in a through-hole format. Ensure the thermal management solution supports the 40 W power dissipation rating at the expected ambient temperature. Verify that the 60 V collector-emitter voltage exceeds the maximum circuit operating voltage with adequate safety margin.

Part Context

This device belongs to the BD677A series of NPN Darlington transistors. It is designed for general-purpose high-power switching and amplification tasks. The TO-126-3 package provides a balance between power handling capacity and ease of integration into standard printed circuit board layouts.

Replacement Considerations

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