This part is a kind of semiconductor called B1443.

Function of this product has 2SB1443.

Manufacturers : Rohm

Image and pinout :

Some of the text within the PDF file :

Power Transistor (−50V, −2A) 2SB1443 Features 1) Low saturation voltage. VCE (sat) = −0.35V (Max.) at IC / IB = −1A / 50mA. 2) Excellent DC current gain characteristics. Dimensions (Unit : mm) ATV Absolute maximum ratings (Ta=25C) Parameter Symbol VCBO VCEO VEBO IC PC Tj Tstg Limits −50 −50 −6 −2 −5 1 150 −55 to +150 Unit V V V A (DC) A (Pulse) ∗1 ∗2 W (1) (2) (3) Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current Collector power dissipation Junction temperature Storage temperature (1) (2) (3) Emitter Collector Base °C °C ∗1 Single pulse, Pw=10ms 2 ∗2 Printed circuit board 1.7mm thick, collector plating 1cm or larger. Packaging specifications and hFE Type 2SB1443 ATV Q − TV2 2500 Package hFE Mark [ ... ]

B1443 PDF Datasheet Download