Deep sleep mode with nano every 4809

[remis]

Hello
I try to turn the nano every in deep sleep mode. The ''old" 328P use a dedicated lib, not applicable for nano every. For atmega 4809 I follow these solution with RTC:

Help needed sleeping the Atmega4809 Arduino Nano Every

My project is a soil moisture sensor, powered by a battery, that is charged with a solar panel, sending data over ethernet-over-nRF24l01 radio (parts under $25, without housing $?) to an MQTT broker (RPi). I have this running on an older Nano and radio. Now I'd like to use the Nano Every. My question is pretty much the same closed question at Sleep Mode Atmega4809 Arduino Nano Every LowPower.h provides a simple way to power down the non-mega CPUs. Granted the max sleep time is 8s, but you c…

I can not go under 9mA current consumption : I disable all 3V3 power on board, I remove also Q1 on TX , RX line: no success.

Does anybody succes turning atmega 4809 in deep sleep , with power mesurement confirmation?
Thank's

[Andonoc]

Hi Remis,
i learned a lot from this post
https://www.avrfreaks.net/comment/2782306
I try to learn the sleep mechanics too.

I never measured the current consumption of the onboard programmer and all the other components but i think they will suck the most current.
Better try with a bare chip (there is a DIP version too) and use the internal oscillators.
you can use the megacoreX core and a microUPDI as a programmer

hope it helps