BD439-BP

Overview

The BD439-BP is an NPN epitaxial silicon power transistor manufactured by Micro Commercial Components. It is housed in a TO-126 (TO-225AA) package. The device features a collector-emitter voltage rating of 80V and a continuous collector current capacity of 3A. Key electrical characteristics include a maximum collector-base voltage of 80V and a collector-emitter saturation voltage of 800mV at specified test conditions. This component is designed for power linear and switching applications.

Feature Summary

• NPN epitaxial silicon construction for robust power handling
• Designed for use in power linear and switching circuits
• Housed in a standard TO-126 plastic package

Applications

• Power linear amplifier circuits
• General purpose switching applications
• Low to medium power electronic systems

Procurement Notes

The BD439-BP is officially listed as obsolete and no longer in production by the manufacturer. Procurement should focus on identifying verified replacement components or alternative sources that can guarantee authenticity. Buyers must verify the condition of available stock carefully, as availability may be limited to surplus inventory. Ensure any substitute part meets the original electrical specifications and package requirements.

Selection Notes

Select this component only if legacy compatibility with the TO-126 package and specific NPN power parameters is required. Given its discontinued status, engineers should evaluate modern equivalents that offer improved thermal performance or availability. Verify that the replacement maintains the necessary voltage and current ratings for the intended circuit design without altering the physical footprint constraints.

Part Context

The BD439 series belongs to a family of silicon epitaxial-base NPN power transistors. While originally produced by various manufacturers including Fairchild and STMicroelectronics under similar part numbers, the BD439-BP specifically denotes the version supplied by Micro Commercial Components. These transistors are generally used in applications requiring moderate power dissipation and reliable switching characteristics.

Replacement Considerations

Public confirmed substitutes include the BD439 from other manufacturers such as Central Semiconductor Corp. and STMicroelectronics. Cross-reference datasheets to ensure pinout and thermal resistance compatibility before substitution.