2SB646-B Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -80 V
• Collector-Base Voltage, max: -120 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -0.05 A
• Collector Dissipation: 0.9 W
• DC Current Gain (h_fe): 60 to 120
• Transition Frequency, min: 140 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92MOD

Here is an image showing the pin diagram of this transistor.The 2SB646-B transistor can have a current gain of 60 to 120. The gain of the 2SB646 will be in the range from 60 to 320, for the 2SB646-C it will be in the range from 100 to 200, for the 2SB646-D it will be in the range from 160 to 320.Sometimes the "2S" prefix is not marked on the package - the 2SB646-B might only be marked "B646-B".The complementary NPN transistor to the 2SB646-B is the 2SD666-B.You can replace the 2SB646-B with the 2N5401C, 2SA1013, 2SA1013R, 2SA1275, 2SA1275-R, 2SA1284, 2SA984K, 2SA984K-D, 2SB560, 2SB560-D, 2SB646A, 2SB646A-B, 2SB647, 2SB647A, 2SB647AB, 2SB647B, BC640, HSB1109S, HSB1109S-B, KSA1013, KSA1013R, KTA1275 or KTA1275R.