2SD1266A 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: 35 W
• DC Current Gain (h_fe): 70 to 320
• Transition Frequency, min: 30 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 2SD1266A transistor can have a current gain of 70 to 320. The gain of the 2SD1266A-O will be in the range from 160 to 320, for the 2SD1266A-P it will be in the range from 120 to 250, for the 2SD1266A-Q it will be in the range from 70 to 150.Sometimes the "2S" prefix is not marked on the package - the 2SD1266A might only be marked "D1266A".The complementary PNP transistor to the 2SD1266A is the 2SB941A.The BDP951 (SOT-223) is the SMD version of the 2SD1266A transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2SD1266A with the 2SC1986, 2SC2075, 2SC3851A, 2SD1274, 2SD1274A, 2SD1274B, 2SD613, 2SD772, 2SD792, 2SD823, BD241B, BD241C, BD243B, BD243C, BD537, BD539B, BD539C, BD539D, BD543B, BD543C, BD545B, BD545C, BD799, BD801, BD809, BD951, BD953, BD955, BDT83, BDT83F, BDT85, BDT85F, BDT87, BDT87F, BDX77, D44H11, D44H11FP, MJE15028, MJE15028G, MJE15030, MJE15030G, MJF15030, MJF15030G, TIP41D, TIP41E, TIP41F, TIP42D, TIP42E or TIP42F.