2SD2137A Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 80 V
• Collector-Base Voltage, max: 80 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 3 A
• Collector Dissipation: 15 W
• DC Current Gain (h_fe): 70 to 250
• Transition Frequency, min: 30 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: MT-4

Here is an image showing the pin diagram of this transistor.The 2SD2137A transistor can have a current gain of 70 to 250. The gain of the 2SD2137A-P will be in the range from 120 to 250, for the 2SD2137A-Q it will be in the range from 70 to 150.Sometimes the "2S" prefix is not marked on the package - the 2SD2137A might only be marked "D2137A".The complementary PNP transistor to the 2SD2137A is the 2SB1417A.The BDP951 (SOT-223) is the SMD version of the 2SD2137A transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.