SAM D20 maximum voltage of ADC reference

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#1
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Datasheet says the maximum voltage for the ADC external reference is VDDANA-0.6V, that is 2.7V if VDDANA=3.3V. Of course this maximum voltage applies to ADC inputs too.

 

What happens if the voltage (on ADC inputs o reference) is in the range [VDDANA-0.6V to VDDANA]? The ADC conversion will surely result in a all-ones value, but is there a risk to damage the device?

In other words, is this maximum value an absolute maximum rating?

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What does the absolute maximum ratings say for the reference input pin?

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I've had a similar issue with the SAMD20 series controllers. We were able to successfully configure the peripheral to scale the reference to VDDANA/2 and half gain to see "full resolution" to the analog pin.