2SB549-S Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -100 V
• Collector-Base Voltage, max: -120 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -0.8 A
• Collector Dissipation: 10 W
• DC Current Gain (h_fe): 40 to 80
• Transition Frequency, min: 70 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-126

Here is an image showing the pin diagram of this transistor.The 2SB549-S transistor can have a current gain of 40 to 80. The gain of the 2SB549 will be in the range from 40 to 320, for the 2SB549-P it will be in the range from 160 to 320, for the 2SB549-Q it will be in the range from 100 to 200, for the 2SB549-R it will be in the range from 60 to 120.Sometimes the "2S" prefix is not marked on the package - the 2SB549-S might only be marked "B549-S".The complementary NPN transistor to the 2SB549-S is the 2SD415-S.You can replace the 2SB549-S with the BD792, MJE253, MJE253G or MJE254.