2SC3940 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 25 V
• Collector-Base Voltage, max: 30 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 1 A
• Collector Dissipation: 1 W
• DC Current Gain (h_fe): 85 to 340
• Transition Frequency, min: 200 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92MOD

Here is an image showing the pin diagram of this transistor.The 2SC3940 transistor can have a current gain of 85 to 340. The gain of the 2SC3940-Q will be in the range from 85 to 170, for the 2SC3940-R it will be in the range from 120 to 240, for the 2SC3940-S it will be in the range from 170 to 340.Sometimes the "2S" prefix is not marked on the package - the 2SC3940 might only be marked "C3940".The complementary PNP transistor to the 2SC3940 is the 2SA1534.The 2SC2859 (SOT-23), 2SC4118 (SOT-323), 2SD874 (SOT-89), KTC3876 (SOT-23) and KTC3876S (SOT-23) is the SMD version of the 2SC3940 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2SC3940 with the 2SC1383, 2SC1384, 2SC3940A, 2SD545, 2SD592 or 2SD592A.