For a precision experiment, I'm considering using AD9650 as the ADC. The input signal from the analog front-end would be of the order of ~ 140 uV. Using the internal reference of the ADC 1.35 V, then a LSB would be ~ 40 uV. I would like to have a LSB value typically < 10 uV, for which I'm planning to use an external reference of the order of 250 mV to obtain a 7 uV LSB.
Will this work in principle? What are some important things that I have to pay attention to when designing this way ? Does ADI recommend any voltage reference ICs for this application?
Guidance would be appreciated greatly!