I have an arduino micro. When running powered with USB from my notebook, I can input all distinct values between 0 to 1023 using a 10K potentiometer with the middle leg on an analog input and the outer ones at ground and 5V from the arduino board.
Somehow, when I use the VI pin for extern power without USB and I plug it to 9,6V (8xAA) the values from the analog input jump around like mad. The voltage seems to be quite unstable. I output the value on an LCD and it's impossible to read them, when running on the 8xAA pack.
Can this be a damage of my board, or did anybody else have similar problems?
Might it help to use a L7805VC to power the arduino micro, or maybe use a capacity on the analog input?
Normaly I never had problems with unstable voltage from batteries and I double checked them and also there is not much load on those batteries, actually only the arduino reading the potentiometer and the LCD, nothing to impress a fully charged 9,6V 2500mAh battery pack.
I hope I picked the right forum for this question, any help is welcome!