So the spec sheet says the external reference voltage can only go as low as 2.0V. Anyone have any idea what exactly happens if it's oh, 1.8V? Does the ADC do nothing? Does it just lose precision? Does the chip explode?
Also the table explaining the bits to set to use it mentions "internal reference turned off". So if I want to us the bandgap reference as the input channel and AREF as the reference is that still fine?