This part is a kind of semiconductor called LD7552B.

Function of this product has Green Mode PWM Controller.

Manufacturers : Leadtrend

Image and pinout :

Some of the text within the PDF file :

LD7552B 1/2/2008 Green-Mode PWM Controller with Integrated Protections Rev. 01a General Description The LD7552B are low cost, low startup current, current mode PWM controllers with green-mode power- saving operation. The integrated functions include the Features z z z z z z z z z z z High-Voltage CMOS Process with Excellent ESD protection Very Low Startup Current (<20μA) Current Mode Control Non-audible-noise Green Mode Control UVLO (Under Voltage Lockout) LEB (Leading-Edge Blanking) on CS Pin Programmable Switching Frequency Internal Slope Compensation OVP (Over Voltage Protection) on Vcc Pin OLP (Over Load Protection) 500mA Driving Capability leading-edge blanking of the current sensing, internal slope compensation. They provide the users a superior AC/DC power [ ... ]

LD7552B PDF Datasheet Download