2SC3954-D Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 120 V
• Collector-Base Voltage, max: 120 V
• Emitter-Base Voltage, max: 3 V
• Collector Current − Continuous, max: 0.3 A
• Collector Dissipation: 8 W
• DC Current Gain (h_fe): 60 to 120
• Transition Frequency, min: 400 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-126F

Here is an image showing the pin diagram of this transistor.The 2SC3954-D transistor can have a current gain of 60 to 120. The gain of the 2SC3954 will be in the range from 40 to 320, for the 2SC3954-C it will be in the range from 40 to 80, for the 2SC3954-E it will be in the range from 100 to 200, for the 2SC3954-F it will be in the range from 160 to 320.Sometimes the "2S" prefix is not marked on the package - the 2SC3954-D might only be marked "C3954-D".The complementary PNP transistor to the 2SC3954-D is the 2SA1539-D.You can replace the 2SC3954-D with the 2SC2481, 2SC2481-R, 2SC2690, 2SC2690-R, 2SC2690A, 2SC2690A-R, 2SC3599, 2SC3599-D, 2SC3621, 2SC3621-R, 2SD600K, 2SD600K-D, 2SD669, 2SD669-B, 2SD669A, 2SD669A-B, KSC2690, KSC2690-R, KSC2690A, KSC2690A-R, MJE341, MJE344 or MJE344G.