AVdd is the analogue supply voltage. If it's to be the same as Vdd, it's usually a good idea to filter it with a RC (or other) to reduce the clocking noise fed into the ADC reference.
AVdd is the analogue supply voltage. If it's to be the same as Vdd, it's usually a good idea to filter it with a RC (or other) to reduce the clocking noise fed into the ADC reference.
Yep, but there may not be a need to amplify it. Set the Vref for 2.048v resolution which will then be 2mV or 0.2'C resolution.
Then average 16 readings over a period of one mains cycle, so the few mV noise picked up by the mains is negated, BUT it also adds a +/- varying factor to the ADC volatge so when you average it you can get double the resoltuion with a fair degree of accuracy.
So you add 16 readings over a mains cycle, then divide the total by 8, (giving you double the resolution) so it is now at a resolution of 0.1'C.
Good point. Oversampling can be used to get a better resolution.
I read somewhere that you only need 4x sampling to get an increase of a bit (of course what you wrote is correct though). So if you have a mains cycle of sampling at 40kHz you can get 14bit resolution (using 10bit ADC)