This part is a kind of semiconductor called BP2831A.
Function of this product has Non-isolated Buck Offline LED Driver.
Manufacturers : BPS
Image and pinout :
Some of the text within the PDF file :
BP2831A 晶丰明源半导体 Description The BP2831A is a high precision buck constant current LED driver. The device operates in critical conduction mode and is suitable for 85Vac~265Vac universal input offline LED lighting. The BP2831A integrates a 500V power MOSFET. With patent pending MOSFET driving technique, the operating current of the IC is very low. So it doesn’t need the auxiliary winding for supplying the chip. It can achieve excellent constant current performance with very few external components, so the system cost and size are minimized. The BP2831A utilizes patent pending current control method. It can achieve precise output current and excellent line regulation. The driver operates in critical conduction mode, the output current does not change with the inductance and LE [ ... ]