thank you both for your replies. I have both a battery monitor and a sensor with a DC offset I wish to read. The DC offsets make most of the ADC's usable range in the upper 1/4 of the ADC counts. Batteries tend to be "dead" long before 0V so in affect have a DC offset as well. I was creating a "level shifted" in analog and came up with this ideal. I was going to just stack a few diodes and a cap on the VeRef- and enable it with an I/O port via a limiting resistor to get something around 1V. All of the reference papers I seen always connect this line to AGND so I wanted to check to see if anyone had done this before or not. looks like it worth a try prototyping and see just what it's performance is. 10bits for 0.5V range is still better than what I have now. PS: Old yellow Cow first helped me online back in 1989 +- 1 year. Thanks a LOT for all of the answers to question I had before I need to even ask! The archives are full of them.
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