The L4941 seems absolutely excellent. How come the arduino board doesn’t use something like that? I mean the dropout seems to be only a couple of hundred millivolts…
Low dropout regulators are more expensive and some are very finnicky about the ESR of the capacitors on
the rail - get it wrong, they oscillate. Unless you need that LDO performance, you tend not to want to pay for it,
either in money or in compromised performance in other specifications.
Also the L4941 is only available in huge package sizes, so would need lots of board area.
And it has 4mA quiescent current, rather large percentage of an Arduino board’s current draw.