This part is a kind of semiconductor called OB3330.
Function of this product has PSR LED Controller.
Manufacturers : On-Bright
Image and pinout :

Some of the text within the PDF file :
On-Bright Electronics--Brighten Your Life OB3330 Page 1 of 1 High PF, High CC, PSR LED Controller OB3330 is a high power factor, primary side regulation LED controller with advanced technology to provide high efficiency and high constant current precision control for LED lighting applications. OB3330 achieves comprehensive protection feature, low external component count and low ripple current. OB3330 solution can be easily designed and manufactured for high performance LED lighting application. Features: ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ Primary-Side Control with Single Stage PFC Topology (PF>0.9) High Current Accuracy Analog Multiplier for High Power Factor Correction Transition Mode (TM) Operation to Achieve High Efficiency Eliminate Opto-coupler and TL431 to [ ... ]
OB3330 PDF Datasheet Download
