Low drop fixed and adjustable positive voltage regulators application note (PDF!) from ST:
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, 1.8V, and 3.3 V. The device is supplied in: SOT-223, DPAK and TO-220. Surface mounted packages optimize the thermal characteristics while offering a relevant space saving advantage. High efficiency is assured by an NPN pass transistor. Only a very common 10 μF minimum capacitor is needed for stability. Chip trimming allows the regulator to reach a very tight output voltage tolerance, within ± 2% at 25 °C.
Application note? Whoops! This is pretty a old part…
Sure, this is useful if one is aiming for bottom-dollar BOM, but there are plenty of better alternatives for hobbyists. Even Raspberry Pi did the sane thing and moved to a modern switching power supply.
“Low drop” is terribly misleading, it was low drop a long, long time ago. Not any more! Note that some ollder datasheets say it’s low drop versus LM317, which is less misleading, but both still use NPNs.
Today it’s better to pick modern low-dropout regulators with internal compensation (more flexible on output capacitor options) or use a buck converter to avoid the heat load in higher current projects.