2SA642 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -25 V
• Collector-Base Voltage, max: -30 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -0.3 A
• Collector Dissipation: 0.4 W
• DC Current Gain (h_fe): 70 to 400
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92

The 2SA642 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 2SA642 transistor can have a current gain of 70 to 400. The gain of the 2SA642G will be in the range from 200 to 400, for the 2SA642O it will be in the range from 70 to 140, for the 2SA642Y it will be in the range from 120 to 240.Sometimes the "2S" prefix is not marked on the package - the 2SA642 might only be marked "A642".The complementary NPN transistor to the 2SA642 is the 2SD227.The KSA642 is the TO-92 version of the 2SA642.You can replace the 2SA642 with the 2SB564A, KSA642, KSB564A, MPS6535, MPS6651, MPS6651G, MPS6652, MPS6652G, MPSW51, MPSW51A, MPSW51AG or MPSW51G.