This part is a kind of semiconductor called DAP018B.

Function of this product has PWM Current-Mode Controller.

Manufacturers : ON Semiconductor

Image and pinout :

Some of the text within the PDF file :

Customer Specific Device from ON Semiconductor DAP018A/B/C/D/F PWM Current-Mode Controller for High-Power Universal Off-Line Supplies • Auto−recovery internal output short−circuit protection • • • • • • • • for A, B, C and D versions. F is latched Adjustable Timer for Improved Short−circuit Protection OTP and OVP Inputs for Improved Robustness +500 mA / −800 mA Peak Current Capability Up to 28 V VCC Operation Improved Creepage Distance between High−voltage and Adjacent Pin Extremely Low No−load Standby Power This is a Pb−Free Device This Device uses Halogen−Free Molding Compound Housed in a SO−14 package, the DAP018X represents an enhanced version of the currently available Speedking controller, the DAP011. With an internal structure operating at a fixe [ ... ]

DAP018B PDF Datasheet Download