BD139 NPN Power Transistor

Description

BD139 Pinout Configuration Pin Number Pin Name Description 1 Emitter Current Drains out through emitter, normally connected to ground 2 Collector Current flows in through the collector, normally connected to the load 3 Base Controls the biasing of the transistor, Used to turn ON or OFF the transistor. Features Plastic casing NPN Transistor Continuous Collector current (IC) is 1.5A Collector-Emitter voltage (VCE) is 80 V Collector-Base voltage (VCB) is 80V Base Current (Ib) is 0.5A Emitter Base Breakdown Voltage (VBE) is 5V DC current gain (hfe) is 40 to 160 Available in To-126 package Note: Complete Technical Details can be found in the BD139 transistor datasheet provided at the bottom of this page. BD139 Transistor Overview BD139 is an NPN transistor hence the collector and emitter will be left open (Reverse biased) when the base pin is held at ground and will be closed (Forward biased) when a signal is provided to the base pin BD139 has a gain value of 40 to 160, this value determines the amplification capacity of the transistor. The maximum amount of current that could flow through the Collector pin is 1.5A, hence we cannot connect loads that consume more than 1.5A using this transistor. To bias a transistor we have to supply current to the base pin, this current (IB) should be limited to 1/10th of the collector current, and the voltage across the base-emitter pin should be 5V maximum. When this transistor is fully biased then it can allow a maximum of 1.5A to flow across