BD675AS

Overview

The BD675AS is an NPN epitaxial silicon Darlington transistor manufactured by onsemi, formerly Fairchild Semiconductor. It features a maximum collector-emitter voltage (VCEO) of 45 V and a continuous collector current of 4 A. The device has a power dissipation rating of 40 W and operates within a junction temperature range up to +150°C. It utilizes a TO-126 through-hole package with a minimum DC current gain (hFE) of 750. The component is identified as obsolete or end-of-life.

Feature Summary

• High current amplification capability suitable for driving loads requiring significant base drive reduction.

Applications

• General-purpose switching applications
• Driver stages in audio amplifier circuits

Procurement Notes

Verify the specific manufacturer origin, as the part is listed under onsemi despite the historical Fairchild association. Confirm the exact status regarding availability, as sources indicate it may be discontinued or subject to limited distribution constraints. Ensure compatibility with existing thermal management designs due to the 40 W dissipation requirement.

Selection Notes

Select this component when high current gain is required for low-level control signals driving higher current loads. Consider the TO-126 package constraints for thermal performance. Evaluate alternative NPN Darlington transistors if the 45 V voltage limit or 4 A current capacity does not match the circuit requirements.

Part Context

This component belongs to the BD675A series of NPN Darlington transistors. It is designed for applications requiring high gain and moderate voltage handling. The 'S' suffix typically denotes a specific tape and reel or bulk packaging variant, though official documentation should be consulted for precise packaging details.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided data. Consult manufacturer cross-reference tools for parametrically similar NPN Darlington transistors with comparable voltage and current ratings.