This part is a kind of semiconductor called AE1501.

Function of this product has PWM BUCK DC/DC CONVERTER.

Manufacturers : Chip-Rail

Image and pinout :

Some of the text within the PDF file :

AE1501 PWM BUCK DC/DC CONVERTER AE1501 ● Features 3.3V, 5V, two fixed output versions TO-263 package Output load current 3A Input voltage range up to 40V Requires only 4 external components 150 kHz fixed frequency internal oscillator TTL shutdown capability Low power standby mode, IQ typically 85 µA High efficiency Thermal shutdown and current limit protection ● General Description The AE1501 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V version. Requiring a minimum number of external components, these regulators are simple to use and inclu [ ... ]

AE1501 PDF Datasheet Download