BD243A Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 60 V
• Collector-Base Voltage, max: 60 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 6 A
• Collector Dissipation: 65 W
• DC Current Gain (h_fe): 30
• Operating and Storage Junction Temperature Range: -65 to +150 °C
• Package: TO-220

Here is an image showing the pin diagram of this transistor.The complementary PNP transistor to the BD243A is the BD244A.The BDP949 (SOT-223) is the SMD version of the BD243A transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the BD243A with the 2N6043, 2N6043G, 2N6044, 2N6044G, 2N6045, 2N6045G, 2N6292, 2N6292G, 2N6293, 2N6387, 2N6387G, 2N6388, 2N6388G, 2N6530, 2N6531, 2N6532, 2N6533, 2SC1985, 2SC1986, 2SC2315, 2SC2316, 2SC2334, 2SC2334K, 2SC2334L, 2SC2334M, 2SC2527, 2SC3254, 2SC3254-Q, 2SC3254-R, 2SC3254-S, 2SC3255, 2SC3255-Q, 2SC3255-R, 2SC3255-S, 2SC3346, 2SC3346-O, 2SC3346-Y, 2SC3710, 2SC3710-O, 2SC3710-Y, 2SC3710A, 2SC3710A-O, 2SC3710A-Y, 2SC3747, 2SC3747-Q, 2SC3747-R, 2SC3747-S, 2SC3748, 2SC3748-Q, 2SC3748-R, 2SC3748-S, 2SC3834, 2SC4153, 2SC4511, 2SC4511-O, 2SC4511-P, 2SC4511-Y, 2SC4512, 2SC4512-O, 2SC4512-P, 2SC4512-Y, 2SC4550, 2SC4550-K, 2SC4550-L, 2SC4550-M, 2SC4551, 2SC4551-K, 2SC4551-L, 2SC4551-M, 2SC4552, 2SC4552-K, 2SC4552-L, 2SC4552-M, 2SD1191, 2SD1192, 2SD1196, 2SD1271, 2SD1271-P, 2SD1271-Q, 2SD1271-R, 2SD1277, 2SD1277-P, 2SD1277-Q, 2SD1277A, 2SD1277A-P, 2SD1277A-Q, 2SD1362, 2SD1362-O, 2SD1362-Y, 2SD1411, 2SD1411-O, 2SD1411-Y, 2SD1411A, 2SD1411A-O, 2SD1411A-Y, 2SD1415, 2SD1415A, 2SD1588, 2SD1588-K, 2SD1588-L, 2SD1588-M, 2SD1826, 2SD1827, 2SD1830, 2SD2495, 2SD2495-O, 2SD2495-P, 2SD2495-Y, 2SD363, 2SD363-O, 2SD363-R, 2SD363-Y, 2SD568, 2SD568-K, 2SD568-L, 2SD568-M, 2SD569, 2SD569-K, 2SD569-L, 2SD569-M, 2SD613, 2SD613-C, 2SD613-D, 2SD613-E, 2SD613-F, 2SD633, 2SD634, 2SD635, 2SD866, 2SD866-P, 2SD866-Q, 2SD866-R, 2SD866A, 2SD866A-P, 2SD866A-Q, 2SD866A-R, BD203, BD243B, BD243C, BD303, BD535, BD535J, BD535K, BD537, BD537J, BD537K, BD543A, BD543B, BD543C, BD545A, BD545B, BD545C, BD645, BD647, BD649, BD651, BD797, BD799, BD801, BD807, BD809, BD897, BD897A, BD899, BD899A, BD901, BDT63, BDT63A, BDT63B, BDT63C, BDT65, BDT65A, BDT65B, BDT65C, BDT81, BDT81F, BDT83, BDT83F, BDT85, BDT85F, BDT87, BDT87F, BDW23A, BDW23B, BDW23C, BDW40, BDW41, BDW41G, BDW42, BDW42G, BDW43, BDW63A, BDW63B, BDW63C, BDW63D, BDW73A, BDW73B, BDW73C, BDW73D, BDW93A, BDW93B, BDW93C, BDW93CF, BDX33A, BDX33B, BDX33BG, BDX33C, BDX33CG, BDX33D, BDX53A, BDX53B, BDX53BG, BDX53C, BDX53CG, BDX53D, BDX77, D44H11, D44H11FP, D44H8, KSC2334, KSC2334O, KSC2334R, KSC2334Y, KSD1588, KSD1588-O, KSD1588-R, KSD1588-Y, KSD363, KSD363-O, KSD363-R, KSD363-Y, KSD568, KSD568-O, KSD568-R, KSD568-Y, KSD569, KSD569-O, KSD569-R, KSD569-Y, MJE15028, MJE15028G, MJF6388, MJF6388G, NTE196, TIP100, TIP100G, TIP101, TIP101G, TIP102, TIP102G, TIP130, TIP130G, TIP131, TIP131G, TIP132, TIP132G, TIP140T, TIP141T, TIP142T, TTC3710B or TTD1415B.