This part is a kind of semiconductor called ISL6545.

Function of this product has 5V or 12V Single Synchronous Buck Pulse-Width Modulation (PWM) Controller.

Manufacturers : Intersil Corporation

Image and pinout :

Some of the text within the PDF file :

Data Sheet ISL6545, ISL6545A March 3, 2011 FN6305.6 5V or 12V Single Synchronous Buck Pulse-Width Modulation (PWM) Controller The ISL6545, ISL6545A makes simple work out of implementing a complete control and protection scheme for a DC/DC stepdown converter driving N-Channel MOSFETs in a synchronous buck topology. Since it can work with either 5V or 12V supplies, this one IC can be used in a wide variety of applications within a system. The ISL6545, ISL6545A (hereafter referred to as “ISL6545x”, except as needed) integrates the control, gate drivers, output adjustment, monitoring and protection functions into a single 8 Ld SOIC or 10 Ld DFN package. The ISL6545x provides single feedback loop, voltage-mode control with fast transient response. The output voltage can be precisely reg [ ... ]

ISL6545 PDF Datasheet Download