onsemi Single Bipolar Transistors BD139

The BD139 is a silicon NPN transistor in a TO-225 package designed for audio amplification and driver applications. It has a collector-emitter voltage rating of 80 V, a collector current rating of 1.5 A, and a total device dissipation of 1.25 W at 25°C ambient temperature. The device has a thermal resistance of 10°C/W from junction to case and 100°C/W from junction to ambient. It features a minimum DC current gain of 25 at 0.5 A collector current and a collector-emitter saturation voltage of up to 0.5 V at 0.5 A collector current and 0.05 A base current. The TO-225 package is rated for operating and storage junction temperatures from -55°C to +150°C.