ESP32-U4WDH , 2 cores, which I recommends
We used a Low consumption LDO
Others iC powered on the board.
...
First we disabled all peripheral we do not need .
In menuconfig and in C-Code because sometime need some peripheral.
Disable 8Mhz internal clock.
Disable everything and let only RTC active.
Wake up every 20 seconds, read ADC or wake up by input on etc pin, depends of the scenario, then go hibernation mode (not easy to setup). But working well with a very low consumption
We achieve 12uA all included
