Esp32 s2 and s3 ADC calibration

[Sheepling]

Hello all, am currently working with the ESP32-S2-DEVKITC (I have an S3 on hand too, but would much prefer a solution on S2 at the moment) . Would it be possible to use the ADC in deep-sleep mode to measure its own voltage source? Given the reference voltage is burnt into the efuse, there seems to be no documentation regarding how to change this internal voltage reference except for the legacy esp_adc.c file.

https://docs.espressif.com/projects/esp ... s/adc.html

[MicroController]

I don't think I quite understand what you mean, but could the ADC Calibration Driver be what you're looking for?

[Sheepling]

Thanks for the updated link, but I was looking for the adc_ll_vref_output function found here: https://github.com/espressif/esp-idf/bl ... l/adc_ll.h

It appears the equivalent to this in the s3 only functions as an abort:
https://github.com/espressif/esp-idf/bl ... l/adc_ll.h

Unfortunately, the l1 is not public API still under heavy development, so I guess I can't really use it reliably at the moment.