A 16-bit delta-sigma analog-to-digital converter (ADC) easily multiplexes eight differential or 16 single-ended channels thanks to a settling time that's shorter than the time for a single ...

The RP2040 is not even close to my first choice for an ADC application. However, you can supply your own VRef to the Pico. I believe that mitigates a lot of the switcher noise people are ...