This part is a kind of semiconductor called LD1117A.

Function of this product has Low drop fixed and adjustable positive voltage regulators.

Manufacturers : ST Microelectronics

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Some of the text within the PDF file :

LD1117A Low drop fixed and adjustable positive voltage regulators Datasheet - production data SOT-223 • Available in ± 2% (at 25 °C) and 4% in full temperature range • High supply voltage rejection: – 80 dB typ. (at 25 °C) • Temperature range: 0 °C to 125 °C TO-220 Description DPAK Features • Low dropout voltage: – 1.15 V typ. @ IOUT = 1 A, 25 °C • Very low quiescent current: – 5 mA typ. @ 25 °C • Output current up to 1 A The LD1117A is a low drop voltage regulator able to provide up to 1 A of output current, available also in adjustable versions (VREF = 1.25 V). In fixed versions, the following output voltages are offered: 1.2 V, 1.8 V, and 3.3 V. The device is supplied in: SOT-223, DPAK and TO-220. Surface mounted packages optimize the thermal characteris [ ... ]

LD1117A PDF Datasheet Download