2SC4278-D Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 150 V
• Collector-Base Voltage, max: 150 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 10 A
• Collector Dissipation: 100 W
• DC Current Gain (h_fe): 60 to 120
• Transition Frequency, min: 20 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-247

Here is an image showing the pin diagram of this transistor.The 2SC4278-D transistor can have a current gain of 60 to 120. The gain of the 2SC4278 will be in the range from 60 to 320, for the 2SC4278-E it will be in the range from 100 to 200, for the 2SC4278-F it will be in the range from 160 to 320.Sometimes the "2S" prefix is not marked on the package - the 2SC4278-D might only be marked "C4278-D".The complementary PNP transistor to the 2SC4278-D is the 2SA1633-D.You can replace the 2SC4278-D with the 2SC2837, 2SC3263, 2SC3280, 2SC3281, 2SC3284, 2SC3519, 2SC3519A, 2SC3519A-O, 2SC3519A-P, 2SC3519A-Y, 2SC3907, 2SC5199, 2SC5200, 2SC5200N, 2SC5242, 2SC5358, 2SC5775, 2SC5948, 2SC5949, 2SC6011, 2SC6011A, 2SC6011A-O, 2SC6011A-P, 2SC6011A-Y, 2SC6145, 2SC6145A, 2SD1717, 2SD1717-Q, 2SD1718, 2SD1718-Q, 2SD2155, FJA4313, FJL4315, KTC5200, KTC5200A, KTC5242, KTC5242A, MAG6333, MJW3281A, MJW3281AG or NTE2328.