This part is a kind of semiconductor called GS1085L.

Function of this product has 3A Low Dropout Voltage Regulator.

Manufacturers : Globaltech

Image and pinout :

Some of the text within the PDF file :

3A Low Dropout Voltage Regulator DEC. 2009 Product Description The GS1085L is a lo w drop voltage regulator able to provid e up to 3A output current. T he dropo ut voltage of the device is gu aranteed at a m aximum 1.3V at the maximum output current, decreasing at lower loads. The GS1085L is pin co mpatible with older 3-terminal adj ustable regul ators, but has better performances in term of drop and output tolerance. Features Three Terminal Adjustable or Fixed Output Voltages 1.5V, 1.8V, 2.5V, 3.3V and 5V  Guaranteed Output Current up to 3A  Typical Dropout 1.3V (at 3A)  Output Tolerance: ±2% at 25 ºC W ind Operating Temperature Range: -40 ºC to 125 ºC  Package Available: TO-220, TO-263, T O-252, and SOT-223  Applications  Post Regulators for Switching Supply [ ... ]

GS1085L PDF Datasheet Download