BD139 Transistor Pinout, Equivalent, Features & More

This article describes BD139 transistor pinout, equivalent, uses, features, applications, how and where to use this transistor in an electronic circuit…

Features / technical specifications:

• Package Type: TO-126
• Transistor Type: NPN
• Max Collector Current(I_C): 1.5A
• Max Collector-Emitter Voltage (V_CE): 80V
• Max Collector-Base Voltage (V_CB): 80V
• Max Emitter-Base Voltage (VEBO): 5V
• Max Collector Dissipation (Pc): 12.5 Watt
• Max Transition Frequency (fT): 190 MHz
• Minimum & Maximum DC Current Gain (h_FE): 25 – 250
• Max Storage & Operating temperature Should Be: -55 to +150 Centigrade

PNP Complementary:

PNP Complementary of BD139 is BD140

Replacement and Equivalent:

BD230, 2SC5171S , BD349, and BD379

BD139 Transistor Explained / Description:

BD139 is a popular NPN transistor used in wide variety of electronic circuits, due to its high collector current and low cost it is an ideal transistor to be used in educational electronic projects and also in commercial electronics. It can drive loads upto 1.5A which is a good feature due to which you can drive many high current components such as high power LEDs, high current relays, motors etc. The collector emitter and collector base voltage is also very high therefore it can easily survive in an electronic circuit that is operated under 80 volts. The collector dissipation is 12.5W due to which it is also ideal to use it in audio amplifier circuits. The saturation voltage of the transistor is just 0.5V.

Where We Can Use it & How to Use:

BD139 is a good transistor to use in hobby and educational electronics projects for example in analog circuits, arduino projects and other microcontroller projects. This transistor can drive loads upto 1500mA therefore you can drive and control many electronic equipment’s through it. It can also be used in commercial electronics. When driving load above 200mA the transistor will dissipate heat due to which using a suitable heatsink is necessary.

Applications:

Audio Amplifiers

Switching Loads under 1.5A

Battery Chargers

Power Supplies

Motor Driver

Darlington Pair

How to Safely Long Run in a Circuit:

To safely run this transistor in your circuit or electronic projects do not operate this transistor from voltage higher than 80V, do not drive load more than 1.5A or 1500mA and use a suitable heat sink with the transistor. Also use a suitable base resistor to provide required base current. The minimum and maximum survival temperature of this transistor is -55 to +150 Centigrade therefore do not expose it to temperatures above +150 centigrade and below -55 centigrade.