BD139 NPN Medium Power Transistor (TO-126, 80V, 1.5A)

The BD139 is a medium-power NPN silicon bipolar junction transistor designed for signal amplification, switching, and driver applications. Its TO-126 through-hole package supports PCB mounting in audio amplifier stages, electronic control circuits, and general-purpose power switching applications. With a specified collector-emitter voltage of 80V and continuous collector current of 1.5A, it is suitable for circuits operating within the transistor's electrical and thermal limits.

Key Features -

• NPN silicon bipolar junction transistor

• Medium-power transistor design

• Collector-emitter voltage rating of 80V

• Continuous collector current rating of 1.5A

• TO-126 through-hole package

• Suitable for signal amplification and switching

• Supports driver and control circuit applications

Specifications -

• Product Type: Bipolar Junction Transistor (BJT)

• Part Number: BD139

• Transistor Polarity: NPN

• Semiconductor Material: Silicon

• Package Type: TO-126

• Mounting Type: Through Hole

• Number of Pins: 3

• Collector-Emitter Voltage (VCEO): 80V, as specified

• Continuous Collector Current (IC): 1.5A, as specified

• Base Current (IB): 0.5A, as provided; verify the maximum rating in the manufacturer's datasheet

• Emitter-Base Breakdown Voltage (VEBO): 5V, as specified

• DC Current Gain (hFE): Depends on operating conditions and manufacturer specifications

• Power Dissipation: Verify according to the manufacturer's datasheet and thermal conditions

• Pin Configuration: Verify the manufacturer's datasheet before installation

Applications -

• Signal amplification circuits

• Audio amplifier driver stages

• General-purpose switching circuits

• Relay and actuator driver circuits

• Electronic control systems

• Industrial electronic equipment

• Educational electronics and repair projects