BD139 Transistor Description

The BD139 is a NPN Bipolar Junction Transistor (BJT) designed for medium power amplification and switching applications. It is widely used in audio amplifiers, motor drivers, and power supply circuits due to its reliable performance and robustness.

Features / Specs:

• Transistor Type: Bipolar Junction Transistor (BJT)
• Transistor Polarity: NPN
• Collector-Emitter Voltage V_CEO Max: 80 V
• Collector-Base Voltage V_CBO: 80 V
• Emitter-Base Voltage V_EBO: 5 V
• Collector-Emitter Saturation Voltage: 500 mV (typical)
• Maximum DC Collector Current: 1.5 A
• Power Dissipation (P_D): 12.5 W
• Maximum Operating Temperature: +150 °C
• Mounting Style: Through Hole
• Package/Case: TO-225

Applications:

• Audio Amplifiers
• Switching Loads under 1.5 A or 1500 mA
• Battery Charger Circuits
• Power Supply Circuits
• Motor Driver Circuits
• Darlington Pair Transistor Configurations

For detailed electrical characteristics and pin configuration, refer to the BD139 Datasheet.