BD139 transistor TO126 CDIL NPN transistor 100V 1.5A CDIL BD139

Product Overview:

A through-hole NPN silicon epitaxial planar medium-power bipolar junction transistor housed in a TO-126 plastic package. Engineered for high-linearity and moderate-power handling, it is a classic choice for driver stages in audio power amplifiers, power supply regulators, and medium-current switching applications like driving small motors, relays, or high-intensity LEDs. It is the direct NPN counterpart to the PNP BD140 transistor.

Core Specifications:

• Manufacturer: CDIL (Continental Device India Limited)

• Package Type: TO-126

• Function: NPN Medium-Power Transistor

• Maximum Collector-Emitter Voltage ($V_{CEO}$): 100V

• Maximum Continuous Collector Current ($I_C$): 1.5A

• Maximum Collector Power Dissipation ($P_C$): 12.5W (at case temperature $T_C = 25^\circ\text{C}$ with proper heatsinking)

• Transition Frequency ($f_T$): 50 MHz (Minimum)

• Common Marking Code: BD139