This part is a kind of semiconductor called LD7591.

Function of this product has Transition-Mode PFC Controller.

Manufacturers : Leadtrend Technology Corporation

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LD7591 04/30/2009 Transition-Mode PFC Controller with Fault Condition Protection Datasheet. P03 (for Internal Use Only) General Description The LD7591 is a voltage mode PFC controller operating on transition mode, integrated several functions of protection, such as OVP, OCP, and Brown-in protection. It minimizes the components counts and is available in a SOP-8 or DIP-8 package. Those make it an ideal design for low cost applications. It provides functions of low startup current, over voltage protection, open feedback protection, disable function, over current protection, under voltage lockout and integrated LEB of the current sensing. Also, the LD7591 features without mains voltage sensing compared with traditional current mode PFC for power saving. The LD7591 can be disabled if the INV [ ... ]

LD7591 PDF Datasheet Download