This part is a kind of semiconductor called FA5591.

Function of this product has Power Supply Control IC.

Manufacturers : Fuji

Image and pinout :

Some of the text within the PDF file :

FA5590N,FA5591N FUJI Power Supply Control IC Power Factor Correction FA5590／FA5591 Application Note Fuji Electric Co., Ltd. AN-016E Rev.1.2 April-2011 April-2011 Fuji Electric Co.,Ltd 1 http://www.fujielectric.co.jp/products/semiconductor/ FA5590N,FA5591N WARNING 1. This Data Book contains the product specifications, characteristics, data, materials, and structures as of April 2011. The contents are subject to change without notice for specification changes or other reasons. When using a product listed in this Data Book, be sure to obtain the latest specifications. 2. All applications described in this Data Book exemplify the use of Fuji’s products for your reference only. No right or license, either express or implied, under any patent, copyright, trade secret or other intellectual [ ... ]

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