This part is a kind of semiconductor called 2SD1897.

Function of this product has (2SD1897 / 2SD1757K) Power Transistor.

Manufacturers : Rohm

Image and pinout :

Some of the text within the PDF file :

Transistors 2SD1897 2SD1757K (96-768-D91) (94S-314-D95) 317 [ ... ]

2SD1897 PDF Datasheet Download