2SA1021-O Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -150 V
• Collector-Base Voltage, max: -150 V
• Emitter-Base Voltage, max: -6 V
• Collector Current − Continuous, max: -1.5 A
• Collector Dissipation: 20 W
• DC Current Gain (h_fe): 100 to 200
• Transition Frequency, min: 50 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 2SA1021-O transistor can have a current gain of 100 to 200. The gain of the 2SA1021 will be in the range from 60 to 320, for the 2SA1021-R it will be in the range from 60 to 120, for the 2SA1021-Y it will be in the range from 160 to 320.Sometimes the "2S" prefix is not marked on the package - the 2SA1021-O might only be marked "A1021-O".The complementary NPN transistor to the 2SA1021-O is the 2SC2481-O.You can replace the 2SA1021-O with the 2SA1249, 2SA1249-R, 2SA1408, 2SA1408-O, 2SA1507, 2SA1507-R, 2SB649A, 2SB649A-C or KTA1700.