The LD1117S33TR is a low drop voltage regulator able to provide up to 800 mA of output current. The SOT-223 package optimizes the thermal characteristics even offering a relevant space saving effect. High efficiency is assured by NPN pass transistor. In fact in this case, unlike than PNP one, the quiescent current flows mostly into the load.
Internal current and thermal limit
75 dB Supply voltage rejection
Very tight output voltage tolerance by chip trimming