This part is a kind of semiconductor called BCP53.

Function of this product has PNP medium power transistors.

Manufacturers : NXP

Image and pinout :

Some of the text within the PDF file :

BCP53; BCX53; BC53PA 80 V, 1 A PNP medium power transistors Rev. 9 19 October 2011 Product data sheet 1. Product profile 1.1 General description PNP medium power transistor series in Surface-Mounted Device (SMD) plastic packages. Table 1. Product overview Type number[1] Package NXP BCP53 SOT223 BCX53 SOT89 BC53PA SOT1061 JEITA SC-73 SC-62 - [1] Valid for all available selection groups. JEDEC TO-243 - NPN complement BCP56 BCX56 BC56PA 1.2 Features and benefits  High current  Three current gain selections  High power dissipation capability  Exposed heatsink for excellent thermal and electrical conductivity (SOT89, SOT1061)  Leadless very small SMD plastic package with medium power capability (SOT1061)  AEC-Q101 qualified 1.3 Applications  Linear v [ ... ]

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