This part is a kind of semiconductor called BC550.

Function of this product has NPN general purpose transistors.

Manufacturers : NXP

Image and pinout :

Some of the text within the PDF file :

DISCRETE SEMICONDUCTORS DATA SHEET book, halfpage M3D186 BC549; BC550 NPN general purpose transistors Product specification Supersedes data of 1997 Jun 20 1999 Apr 22 Philips Semiconductors Product specification NPN general purpose transistors FEATURES • Low current (max. 100 mA) • Low voltage (max. 45 V). APPLICATIONS • Low noise stages in audio frequency equipment. DESCRIPTION NPN transistor in a TO-92; SOT54 plastic package. PNP complements: BC559 and BC560. 1 handbook, halfpage BC549; BC550 PINNING PIN 1 2 3 emitter base collector DESCRIPTION 2 3 3 2 1 MAM182 Fig.1 Simplified outline (TO-92; SOT54) and symbol. LIMITING VALUES In accordance with the Absolute Maximum Rating System (IEC 134). SYMBOL VCBO BC549 BC550 VCEO collector-emitter voltage BC549 BC550 VEBO IC I [ ... ]

BC550 PDF Datasheet Download