Consider an ESP-01 that is powered by a 3.3v (OR LESS) regulator hooked to a 18650 battery (3.7v ~ 4.2v) hooked to a TP4056 charger randomly obtaining power from 2 solar panels in series giving approx 5.5v when in full sun exposure.
Now ordering a KA75330 to also prevent an UNDER VOLTAGE condition, in the hope of preventing an ESP-01 brownout, which I just learned, almost always ends up completely stalling/halting the ESP-01. I was pulling my hair out today trying to figure out why the ESP-01 LED was lit, but the damn thing was doing nothing. This happens very often at random in the morning when the battery begins to charge up in the first sun rays and reaches around 2.5v and then the ESP-01 boots but it just immediately AND SILENTLY halts with its LED still on, giving the false impression that it is still running, but it's not! When this happens, I disconnect the 3.3v pin and wait an hour for the battery to charge a little more and reach the ESP-01 base voltage threshold (approx. 2.8v) and then I hook the 3.3v pin again and this resets the ESP-01 and it works for the rest of the day perfectly fine.
I saw this tutorial and it explains exactly that issue plus a solution (KA75330) but the video omits to explain what resistor value is needed if the Vcc is 3.3v or less.
QUESTION IS: What resistor value is needed in this case?