BD179 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 80 V
• Collector-Base Voltage, max: 80 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 3 A
• Collector Dissipation: 30 W
• DC Current Gain (h_fe): 40 to 250
• Transition Frequency, min: 3 MHz
• Operating and Storage Junction Temperature Range: -65 to +150 °C
• Package: TO-126

Here is an image showing the pin diagram of this transistor.The BD179 transistor can have a current gain of 40 to 250. The gain of the BD179-10 will be in the range from 63 to 160, for the BD179-6 it will be in the range from 40 to 60.The complementary PNP transistor to the BD179 is the BD180.The BDP951 (SOT-223) is the SMD version of the BD179 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the BD179 with the BD789, BD791, MJE242 or MJE244.