2SA643G Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -20 V
• Collector-Base Voltage, max: -40 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -0.5 A
• Collector Dissipation: 0.5 W
• DC Current Gain (h_fe): 200 to 400
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92

The 2SA643G is manufactured in a plastic TO-92 case. When looking at the flat side with the leads pointed downward, the three leads emerging from the transistor are, from left to right, the emitter, base, and collector leads.
Here is an image showing the pin diagram of this transistor.The 2SA643G transistor can have a current gain of 200 to 400. The gain of the 2SA643 will be in the range from 40 to 400, for the 2SA643O it will be in the range from 70 to 140, for the 2SA643R it will be in the range from 40 to 80, for the 2SA643Y it will be in the range from 120 to 240.Sometimes the "2S" prefix is not marked on the package - the 2SA643G might only be marked "A643G".The complementary NPN transistor to the 2SA643G is the 2SD261G.The KSA643G is the TO-92 version of the 2SA643G.You can replace the 2SA643G with the 2SB564A, 2SB564AGR, KSA643, KSA643G, KSB564A, KSB564AG, MPS6535, MPS6651, MPS6651G, MPS6652, MPS6652G, MPS750, MPS750G, MPSW51, MPSW51A, MPSW51AG or MPSW51G.