2SB1157-S Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -100 V
• Collector-Base Voltage, max: -100 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -5 A
• Collector Dissipation: 60 W
• DC Current Gain (h_fe): 80 to 160
• Transition Frequency, min: 20 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-3PF

Here is an image showing the pin diagram of this transistor.The 2SB1157-S transistor can have a current gain of 80 to 160. The gain of the 2SB1157 will be in the range from 60 to 200, for the 2SB1157-P it will be in the range from 100 to 200, for the 2SB1157-Q it will be in the range from 60 to 120.Sometimes the "2S" prefix is not marked on the package - the 2SB1157-S might only be marked "B1157-S".The complementary NPN transistor to the 2SB1157-S is the 2SD1712-S.The BDP954 (SOT-223) is the SMD version of the 2SB1157-S transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2SB1157-S with the 2SA1141, 2SA1673, 2SA1860, 2SA1908, 2SA1909, 2SB1054, 2SB1055, 2SB1056, 2SB1057, 2SB1158, 2SB1158-S, 2SB1159, 2SB1159-S, 2SB1160, 2SB1160-S, 2SB1161, 2SB1161-S or FJAF4210.