This part is a kind of semiconductor called AX1212A.

Function of this product has 1.2V Output 1A LOW Dropout Linear Regulator.

Manufacturers : AXElite

Image and pinout :

Some of the text within the PDF file :

AX1212A 1.2V Output 1A LOW Dropout Linear Regulator  GENERAL DESCRIPTION AX1212A is a low dropout positive 1.2V output regulator with minimum of 1A output current capability. The product is specifically designed to provide well-regulated supply for low voltage IC applications. AX1212A is also well suited for other applications such as VGA cards. AX1212A is guaranteed to have lower than 1.5V dropout at full load current making it ideal to provide well-regulated outputs of 1.2V with 2.6V to 12V input supply.  FEATURES Fixed 1.2V + 2% output voltage 1.5V maximum dropout at full load current Low-ESR Ceramic Capacitor (MLCC) Required for Stability Fast transient response Output current limiting Built-in thermal shutdown Good noise rejection Pb-Free Packages: SOT223, TO252  BLOCK DIAGR [ ... ]

AX1212A PDF Datasheet Download