As far as I know, there is only one place in the lower US that has a
requirement for the pilot to carry a current (paper) chart on board - and if
memory serves, the requirement is for a terminal area chart - and that is
when transitioning the VFR corridor over the Los Angeles, CA International
Airport (LAX). There may be others like this one but it's the only one with
which I'm familiar.

There are several other rules specific to this corridor (specified VOR
radials and altitude for direction of flight, e.g., NW or SE, Xponder squawk
1201, blind position announce on special freq. while in corridor, no ATC
clearance required, lights ON, and maybe a couple of others as well - it's
been a while since I regularly flew in that area).

These are all the result of regaining the use of the corridor following it's
closure after a collision between a GA aircraft and a Mexicana Airline DC-9
over a LA suburb some years ago. (The crash was not in the then existing
corridor but it was closed for a long time anyway).

Bottom line: if you plan to fly in the LA area, have the current paper TA
chart on board.

Dan Schaefer