Product Description
The 8550 is a high-current, general-purpose PNP epitaxial silicon transistor designed for a wide variety of switching and amplification applications. While many standard small-signal transistors are limited to 100mA, the S8550 can handle a continuous collector current of up to 700mA in some variants, making it exceptionally useful for driving small DC motors, high-power LEDs, and relay coils. Housed in the universal TO-92 plastic package, it is a staple component for hobbyists and engineers alike. It is frequently paired with its NPN counterpart, the S8050, to create efficient Class-B push-pull audio amplifiers or H-bridge motor controllers.
Key Features
High Current Handling: Capable of driving loads up to 500mA–700mA, bridging the gap between small-signal and medium-power transistors.
Low Saturation Voltage: Ensures minimal power loss and heat generation when the transistor is used as a fully "ON" switch.
High Gain ($h_{FE}$): Provides excellent amplification factor, allowing a very small base current to control a much larger load current.
Complementary Pair: Specifically designed to work in tandem with the S8050 (NPN) for symmetrical circuit designs.
Robust TO-92 Package: The compact, 3-pin through-hole design is easy to solder and fits perfectly into standard breadboards and stripboards.