This part is a kind of semiconductor called LM317L.

Function of this product has Positive Voltage Regulator.

Manufacturers : ON Semiconductor

Image and pinout :

Some of the text within the PDF file :

LM317L, NCV317L 100 mA Adjustable Output, Positive Voltage Regulator The LM317L is an adjustable 3−terminal positive voltage regulator capable of supplying in excess of 100 mA over an output voltage range of 1.2 V to 37 V. This voltage regulator is exceptionally easy to use and requires only two external resistors to set the output voltage. Further, it employs internal current limiting, thermal shutdown and safe area compensation, making them essentially blow−out proof. The LM317L serves a wide variety of applications including local, on card regulation. This device can also be used to make a programmable output regulator, or by connecting a fixed resistor between the adjustment and output, the LM317L can be used as a precision current regulator. Features  Output Current in Excess [ ... ]

LM317L PDF Datasheet Download