This part is a kind of semiconductor called AIC2565.

Function of this product has 23V 3A Step-Down DC/DC Converter.

Manufacturers : Analog Integrations Corporation

Image and pinout :

Some of the text within the PDF file :

AIC2565 23V 3A Step-Down DC/DC Converter  FEATURES  3A Continuous Output Current  Programmable Soft Start  100mΩ Internal Power MOSFET Switch  Stable with Low ESR Output Ceramic Capacitors  Up to 95% Efficiency  22µA Supply Current in Shutdown Mode  Fixed 385KHz Frequency  Thermal Shutdown  Cycle by Cycle Over Current Protection  Wide 4.75 to 23V Operating Input Range  Output Adjustable from 1.22V to 16V  Under Voltage Lockout  APPLICATIONS  Networking Products  Distributed Power Systems  Battery Charger  Pre-Regulator for Linear Regulators.  TYPICAL APPLICATIONS CIRCUIT  DESCRIPTION The AIC2565 is a high efficiency, step-down DC/DC converter that builds in a high side power MOSFET. It offers continuous 3A output current over [ ... ]

AIC2565 PDF Datasheet Download