This part is a kind of semiconductor called LD7577.
Function of this product has High Voltage Green-Mode PWM Controller.
Manufacturers : Leadtrend
Image and pinout :
Some of the text within the PDF file :
LD7577 1/15/2009 High Voltage Green-Mode PWM Controller with Brown-Out Protection Rev. 01 General Description The LD7577 integrates several functions of protections, and EMI-improved solution in SOP-8 package. It minimizes the component counts and the circuit space. The device provides functions of low startup current, green-mode power-saving operation, leading-edge blanking of the current sensing and internal slope compensation. Also, it features more protections like OLP (Over Load Protection), OVP (Over Voltage Protection), and brownout protection to prevent the circuit from being damaged under abnormal conditions. Features z z z z z z z z z z z High-Voltage (500V) Startup Circuit Current Mode Control Non-Audible-Noise Green Mode Control UVLO (Under Voltage Lockout) LEB (Leading-Edg [ ... ]