This part is a kind of semiconductor called A7596.

Function of this product has 3A PWM BUCK DC-DC CONVERTER.

Manufacturers : AiT Semiconductor

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Some of the text within the PDF file :

AiT Semiconductor Inc. www.ait-ic.com A7596 DC-DC CONVERTER/ BUCK (STEP-DOWN) 150KHz, 3A PWM BUCK DC-DC CONVERTER DESCRIPTION FEATURES The A7596 series of regulators are monolithic  5V and adjustable output versions integrated circuits that provide all the active functions  Adjustable version output voltage range 1.23V for a step-down (buck) switching regulator, capable of to 37V driving a 3A load with excellent line and load  Input voltage range up to 40V regulation. These devices are available in fixed output  Guaranteed 3A output current voltage of 5V and adjustable output version.  150KHz fixed frequency internal oscillator  Built-in thermal shutdown and current limit The A7596 operates at a switching frequency of protection 150KHz thus allowing smaller [ ... ]

A7596 PDF Datasheet Download