2SA1837 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -230 V
• Collector-Base Voltage, max: -230 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -1 A
• Collector Dissipation: 20 W
• DC Current Gain (h_fe): 100 to 320
• Transition Frequency, min: 70 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-220F

Here is an image showing the pin diagram of this transistor.Sometimes the "2S" prefix is not marked on the package - the 2SA1837 might only be marked "A1837".The complementary NPN transistor to the 2SA1837 is the 2SC4793.You can replace the 2SA1837 with the 2SA1006B, MJE15033, MJE15033G, MJE15035, MJE15035G, MJE5850, MJE5850G, MJE5851, MJE5851G, MJE5852 or MJE5852G.