LImits AREF pin

Hi, I am doing a project which need a high resolution of voltaje and I have seen that I can obtain more accurate results using the function analogReference(EXTERNAL). I have been using analogReference(INTERNAL) but the voltaje I obtain is less than 1V, so I would like to know if I can apply less than 1V to the AREF pin. I see in internet that it can give some problems. Can I apply less than 1V or an amplifier?

Thank you.

Yes! However read the data, you can damage the chip if not done correctly. You can program some of the Arduinos to use there internal voltage reference, I believe is in the 1.1 volt range with the statement it is not to stable. I do not know if that means from chip to chip. My experience in the past with other manufacturers is it is the voltage is stable on a chip by chip basis but not from chip to chip. Consider using an external amplifier to adjust your signal to the 0 to 5V needed and DO NOT connect other loads to the 5V output as this will cause errors. In software you can actually get the VREF voltage and adjust your readings according to this value each time you do a conversion.
Good Luck & Have Fun!
Gil

ElGranMostaza:
I would like to know if I can apply less than 1V to the AREF pin. I see in internet that it can give some problems. Can I apply less than 1V or an amplifier?

The Atmega328 datasheet (assuming you are talking about an Uno) states AFAIK a minimum Aref voltage of 1volt. You can go lower than that, but no guarantees that it will work as expected.

An amplifier could work, but you first need to tell us more about your project.
Leo..

gilshultz:
You can program some of the Arduinos to use there internal voltage reference, I believe is in the 1.1 volt range with the statement it is not to stable.

Most common Arduinos have a 1.1volt Aref, some have more than one Aref.
The 1.1volt Aref is stable, but not exactly 1.1volt.
Because it's not factory calibrated, you must do that yourself for each individual Arduino.
You could simply write it on the board once you know.
Leo..