I'm pretty new to all this and I'm trying to get a simple analog to digital test circuit hooked up.
I have a +5V voltage regulator with a couple capacitors hooked up to supply power to at atmega16, and that all works great. However, when I introduce a variable resistor to vary the voltage being applied to one of the analog to digital pins of the chip, I see small changes in voltage throughout my circuit.
Without the variable resistor I see 4.95V being supplied as VCC. When I add the variable resistor I see VCC vary between 4.90V and 4.95V between the two extremes.
Is this expected? Will this cause problems if I added more variable resistors to some of the other ADC pins? How can I use a potentiometer to vary voltage to a pin, without changing the voltage in my entire circuit?