STMicroelectronics Transistor 3 A NPN 80 V 3-Pin SOT-32 BD139

The STMicroelectronics BD139 is a general-purpose NPN bipolar junction transistor designed for switching and amplification applications. It features a 3-pin SOT-32 package with through-hole mounting suitable for various industrial and electronic uses requiring medium power and voltage capabilities.

With a maximum DC collector current rating of 3 A and collector-emitter voltage of 80 V, this transistor efficiently handles moderate power loads. The device supports a power dissipation rating of 1.25 W, enabling stable operation under normal circuit conditions.

BD139 offers a minimum DC current gain (hFE) of 25 and maximum emitter base voltage of 5 V, making it well-suited for amplification tasks. Its compact physical size of 27.05 mm length, 7.8 mm width, and 2.9 mm height allows flexible PCB integration while maintaining performance.

The maximum operating temperature of 150°C ensures reliable function in demanding environments common in industrial, laboratory, and electronic manufacturing applications. This transistor is ideal for use in power regulators, drivers, and inverter circuits among other typical electronic applications.

Maximum collector current of 3 A ensuring reliable performance in switching and amplification. Collector-emitter voltage rating of 80 V suitable for medium voltage applications. Power dissipation of 1.25 W allowing safe thermal management in circuits.

Through-hole mount type for easy integration into PCB designs. Minimum DC current gain (hFE) of 25 providing good amplification characteristics. Compact dimensions with 27.05 mm length, 7.8 mm width, and 2.9 mm height. Maximum operating temperature up to 150°C for durable operation in harsh environments.

Designed for general-purpose applications in power and signal amplification circuits. Manufactured in China maintaining standard quality compliance. 3-pin configuration compatible with standard transistor sockets and layouts.

This product belongs in the Bipolar Transistors category, used widely across electronic device manufacturing, industrial equipment, and lab instrumentation circuits. For more transistor options and semiconductor components, browse EnvMart's extensive electronics catalogue.