This part is a kind of semiconductor called BCP53.

Function of this product has PNP General Purpose Amplifier.

Manufacturers : Fairchild Semiconductor

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BCP53 PNP General-Purpose Amplifier March 2014 BCP53 PNP General-Purpose Amplifier Description This device is designed for general-purpose mediumpower amplifiers and switching circuits for collector currents to 1.0 A. Sourced from process 79. 4 3 2 1 SOT-223 1. Base 2,4. Collector 3. Emitter Ordering Information Part Number BCP53 Marking BCP53 Package SOT-223 4L Packing Method Tape and Reel Absolute Maximum Ratings(1),(2) Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratin [ ... ]

BCP53 PDF Datasheet Download