This part is a kind of semiconductor called BCW71.

Function of this product has NPN EPITAXIAL SILICON TRANSISTOR.

Manufacturers : Fairchild Semiconductor

Image and pinout :

Some of the text within the PDF file :

BCW71 GENERAL PURPOSE TRANSISTOR NPN EPITAXIAL SILICON TRANSISTOR SOT-23 ABSOLUTE MAXIMUM RATINGS (TA=25° C) Characteristic Collector-Base Voltage Collector-Emitter Voltage Emitter-Base Voltage Collector Current Collector Dissipation Storage Temperature • Refer to KST2222 for graphs Symbol VCBO VCEO VEBO IC PC T STG Rating 50 45 5 100 350 150 Unit V V V mA mW °C 1. Base 2. Emitter 3. Collector ELECTRICAL CHARACTERISTICS (TA=25° C) Characteristic Collector-Base Breakdown Voltage Collector-Emitter Breakdown Voltage Collector-Emitter Breakdown Voltage Emitter-Base Breakdown Voltage Collector Cut-off Current DC Current Gain Collector-Emitter Saturation Voltage Base-Emitter Saturation Voltage Base-Emitter On Voltage Current Gain Bandwidth Product Output Capacitance Noise Figures Symbo [ ... ]

BCW71 PDF Datasheet Download