S8550D Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -25 V
• Collector-Base Voltage, max: -40 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -0.5 A
• Collector Dissipation: 0.625 W
• DC Current Gain (h_fe): 160 to 300
• Transition Frequency, min: 150 MHz
• Operating and Storage Junction Temperature Range: -65 to +150 °C
• Package: TO-92

The S8550D 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 S8550D transistor can have a current gain of 160 to 300. The gain of the S8550 will be in the range from 85 to 300, for the S8550B it will be in the range from 85 to 160, for the S8550C it will be in the range from 120 to 200.The complementary NPN transistor to the S8550D is the S8050D.You can replace the S8550D with the 2N4403, 2SB564A, BCX79, KN2907, KSB564A, KTC8550, KTC8550D, KTN2907, M8550, M8550-D, MPS2907, MPS2907G, MPS3702, MPS6535, MPS6651, MPS6651G, MPS6652, MPS6652G, MPS750, MPS750G, MPS8550, MPS8550D, MPSW51, MPSW51A, MPSW51AG, MPSW51G, PN200, PN2905, PN2907, S9012, SS8550, SS8550D, ZTX549, ZTX550 or ZTX949.