Can arduino zero read 0.5mV reliably using 1v internal reference?

I would like to know if the arduino zero's analog pins can reliably read 0.5mV increments using the 1v internal reference?

at 12bits it should be possible, but mine did not arrive yet, so i cant test it

What does the processor data sheet say?

I have not checked because doubt they would be accurate because a lot can affect ADC reading performance, the pcb layout, and component selections play a lot. Especially the powersupply.

hence i am asking for first hand experience.

In practice noise limits the smallest steady level you can measure. So integrating a sensitive A/D converter on a chip with lots of digital switching going on is never going to be the best solution.

Yes, i agree with you.

Thats why i want to know the steady level of the arduino Zero that is using 1v internal reference :slight_smile:

The whole point of an internal reference is to minimize dependence on the power supply voltage. A small board like the Zero won't have much in the way of signal conditioning for an A/D conversion, if anything. But it's unlikely that very many people here have quantified the noise in depth. What is your application?

It can do that.

The analog input(s) of the ESP8266 and the ESP32 are very bad, but the analog inputs of the AVR and SAMD processors are very good.

I recently learned that the SAMD can do oversampling in hardware. But you can always use the average of many analogRead() values. That way you get more resolution. The linearity of the ADC and overall accuracy does not increase. It is nevertheless a big improvement.

You have to determine the actual value of the 1V reference and use that value in your sketch.

It is very easy to lift the GND a few millivolts with a ground current, so you have to know about ground currents to get the best result.