2SA1537 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -70 V
• Collector-Base Voltage, max: -80 V
• Emitter-Base Voltage, max: -3 V
• Collector Current − Continuous, max: -0.5 A
• Collector Dissipation: 10 W
• DC Current Gain (h_fe): 40 to 320
• Transition Frequency, min: 700 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-126F

Here is an image showing the pin diagram of this transistor.The 2SA1537 transistor can have a current gain of 40 to 320. The gain of the 2SA1537-C will be in the range from 40 to 80, for the 2SA1537-D it will be in the range from 60 to 120, for the 2SA1537-E it will be in the range from 100 to 200, for the 2SA1537-F it will be in the range from 160 to 320.Sometimes the "2S" prefix is not marked on the package - the 2SA1537 might only be marked "A1537".The complementary NPN transistor to the 2SA1537 is the 2SC3952.You can replace the 2SA1537 with the 2SB548, 2SB549, BD170, BD238, BD238G, BD380, MJE252, MJE254 or MJE712.