2SD555 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 200 V
• Collector-Base Voltage, max: 200 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 10 A
• Collector Dissipation: 200 W
• DC Current Gain (h_fe): 40 to 200
• Transition Frequency, min: 15 MHz
• Operating and Storage Junction Temperature Range: -65 to +150 °C
• Package: TO-3

Here is an image showing the pin diagram of this transistor.The 2SD555 transistor can have a current gain of 40 to 200. The gain of the 2SD555-Q will be in the range from 100 to 200, for the 2SD555-R it will be in the range from 60 to 120, for the 2SD555-S it will be in the range from 40 to 80.Sometimes the "2S" prefix is not marked on the package - the 2SD555 might only be marked "D555".The complementary PNP transistor to the 2SD555 is the 2SB600.You can replace the 2SD555 with the 2N6676, 2N6677, 2N6678, 2SD746A, 2SD753, BUX48, BUX80, BUY69A, BUY69B, BUY69C, BUY70A, BUY70B or BUY70C.