2SD743A-Q Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 100 V
• Collector-Base Voltage, max: 100 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 4 A
• Collector Dissipation: 40 W
• DC Current Gain (h_fe): 100 to 200
• Transition Frequency, min: 10 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-220

Here is an image showing the pin diagram of this transistor.The 2SD743A-Q transistor can have a current gain of 100 to 200. The gain of the 2SD743A will be in the range from 40 to 200, for the 2SD743A-R it will be in the range from 60 to 120, for the 2SD743A-S it will be in the range from 40 to 80.Sometimes the "2S" prefix is not marked on the package - the 2SD743A-Q might only be marked "D743A-Q".The complementary PNP transistor to the 2SD743A-Q is the 2SB703A-Q.The BDP953 (SOT-223) is the SMD version of the 2SD743A-Q transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2SD743A-Q with the 2SC2334, 2SC2527, 2SC3834, 2SC4153, 2SD1355, 2SD1407, 2SD1407A, 2SD2059, 2SD363, 2SD525, 2SD772, 2SD772A, 2SD792, 2SD792A, 2SD866A, BD243C, BD539C, BD539D, BD543C, BD545C, BD801, BD953, BD955, BDT85, BDT85F, BDT87, BDT87F, BDT95, BDT95F, KSC2334, KSD363, KTC2018, KTC2028, KTD2059, MJE15028, MJE15028G, MJE15030, MJE15030G, MJF15030, MJF15030G, TIP41D, TIP41E, TIP41F, TIP42D, TIP42E or TIP42F.