2SD1273 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 60 V
• Collector-Base Voltage, max: 80 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 3 A
• Collector Dissipation: 40 W
• DC Current Gain (h_fe): 500 to 2500
• Transition Frequency, min: 50 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 2SD1273 transistor can have a current gain of 500 to 2500. The gain of the 2SD1273O will be in the range from 1200 to 2500, for the 2SD1273P it will be in the range from 800 to 1500, for the 2SD1273Q it will be in the range from 500 to 1000.Sometimes the "2S" prefix is not marked on the package - the 2SD1273 might only be marked "D1273".The complementary PNP transistor to the 2SD1273 is the 2SB1299.You can replace the 2SD1273 with the 2N6531, 2N6533, 2SC1985, 2SC1986, 2SC2075, 2SC2315, 2SC2316, 2SC3179, 2SC3852, 2SC3852A, 2SD1273A, 2SD1274, 2SD1274A, 2SD1274B, 2SD823, BD203, BD241A, BD241B, BD241C, BD243A, BD243B, BD243C, BD303, BD535, BD537, BD539A, BD539B, BD539C, BD539D, BD543A, BD543B, BD543C, BD545A, BD545B, BD545C, BD797, BD799, BD801, BD807, BD809, BD949, BD951, BD953, BD955, BDT81, BDT81F, BDT83, BDT83F, BDT85, BDT85F, BDT87, BDT87F, BDX53D, BDX77, D44H11, D44H11FP, D44H8, KSD1273, MJE15028, MJE15028G, TIP41D or TIP42D.