Excuse me for my English I’m French
I’m using a Nano Every for measuring temperature with NTC. I first use USB port to supply the Arduino. When I convert the analog signal with 10 bits ADC of the Arduino the digital value is very stable (+/- 1bit) everything fine till then…
But when I supply the device with a 12V power supply passing by the onboard 5V regulator (MPM3610) the digital value becomes more instable (+/- 10bits).
I can see on my scope the ripple of 5v supply is more than 100mv !
I tried using a very precise laboratory power supply with same result.
When I supply the arduino directly with 5V power supply the problem disappears…
The onboard 5V regulator seems very noisy ! The datasheet of MPM3610 shows a maximum output ripple of 10mv for 1A load, my circuit needs only 100mA !
It may be a faillure on this particular Arduino or anyone already had this kind of problem ?
Many thanks for helping me !