but since the ADC only draws 160 nA when reading an analog input I doubt it is a problem.
I don't see what that has to do with what I said, I was just showing the voltage at each node would be and how useless it would be to try and use it.
The answer is what I told the OP before but he didn't seem to be listening.
The other answer is to use a R 2R ladder like this:-
