2SB544D Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -25 V
• Collector-Base Voltage, max: -25 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -1 A
• Collector Dissipation: 0.9 W
• DC Current Gain (h_fe): 60 to 120
• Transition Frequency, min: 180 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 2SB544D transistor can have a current gain of 60 to 120. The gain of the 2SB544 will be in the range from 60 to 560, for the 2SB544E it will be in the range from 100 to 200, for the 2SB544F it will be in the range from 160 to 320, for the 2SB544G it will be in the range from 280 to 560.Sometimes the "2S" prefix is not marked on the package - the 2SB544D might only be marked "B544D".The complementary NPN transistor to the 2SB544D is the 2SD400D.You can replace the 2SB544D with the 2N6106, 2N6108, 2N6109, 2N6109G, 2N6111, 2N6111G, 2N6489, 2N6489G, 2SA490, 2SA671, 2SA671-B, 2SA748, 2SA754, 2SA754-B, 2SA755, 2SA755-B, 2SB1185, 2SB1185D, 2SB434, 2SB435, 2SB511, 2SB511-D, 2SB514, 2SB514D, 2SB565, 2SB565-B, 2SB566, 2SB566-B, 2SB632, 2SB632-D, 2SB632K, 2SB632K-D, 2SB857, 2SB857-B, 2SB947A, 2SB947A-R, 2SB948A, 2SB948A-R, BD202, BD240, BD242, BD244, BD302, BD534, BD540, BD544, BD546, BD706, BD734, BD736, BD738, BD744, BD796, BD906, BD934, BD934F, BDT30, D44C1, D44C2, D44C3, D44C4, D44C5, D44C6, D45C1, D45C2, D45C3, D45C4, D45C5 or D45C6.