This part is a kind of semiconductor called BP1808.

Function of this product has Buck and Buck-Boost DC/DC LED Driver.

Manufacturers : BPS

Image and pinout :

Some of the text within the PDF file :

BP1808 晶丰明源半导体 Boost, Buck and Buck-Boost DC/DC LED Driver Description The BP1808 is a DC/DC constant current LED driver with an integrated 70V/300mΩ MOSFET designed for a wide input-voltage range of 3V to 60V. The BP1808 can be configured as Buck, Boost and BuckBoost topology. With a current sense reference of 200mV, the LED current is programmed by an external current sense resistor and the power loss is minimized. The BP1808 allows both analog and PWM dimming by DIM pin. The fixed 420kHz operating frequency minimizes size of external inductor, input and output capacitor. Current mode operation provides fast transient response and easy loop stability. BP1808 offers rich protection functions including VDD under voltage protection, output over voltage protection, cycle-by-c [ ... ]

BP1808 PDF Datasheet Download