2SC3944A Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 180 V
• Collector-Base Voltage, max: 180 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 1 A
• Collector Dissipation: 15 W
• DC Current Gain (h_fe): 65 to 330
• Transition Frequency, min: 200 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-220F

Here is an image showing the pin diagram of this transistor.The 2SC3944A transistor can have a current gain of 65 to 330. The gain of the 2SC3944A-P will be in the range from 65 to 110, for the 2SC3944A-Q it will be in the range from 90 to 155, for the 2SC3944A-R it will be in the range from 130 to 220, for the 2SC3944A-S it will be in the range from 185 to 330.Sometimes the "2S" prefix is not marked on the package - the 2SC3944A might only be marked "C3944A".The complementary PNP transistor to the 2SC3944A is the 2SA1535A.The KST43 (SOT-23) is the SMD version of the 2SC3944A transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2SC3944A with the 2SC1913A, 2SC4382, 2SD772A, 2SD772B, 2SD792A, 2SD792B, MJE15032 or MJE15032G.