AVR-Chat

>> - Should I be using VCC as my AREF?
>
>Only if it is low noise. Atleast feed it thru an RC filter.
>
>> - Should I be using something other than the Int.Ref 2.56v for AREF?
>
>Not needed. Filter AREF with a cap tho.
>
>> - What would be regarded as a 'smooth' VCC or AREF? My VCC at the moment
>> is fluctuating by about 20mV according to the scope.
>
>4 bits is 40mVpk for AREF=5V. Make sure the REF is 1/10th as noisy atleast.
>
>> Any comments, tips suggestions or advice would be most welcome.
>
>Make sure ground pins are connected to a good grounding system.
>For extra low noise, don't switch any loads on the same port as
>the ADC pins during sampling.

Thanks for the info Russell, I will check out RC filters and try smooth the VCC some more.
 
Stuart Whelan