Configuring the AD9826

Document created by analog-archivist Employee on Feb 23, 2016
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I want to use the AD9826 to sample pixel data coming from a NIR-sensor. The
pixel data is between 1.2V and 3.2V. Is it possible to use external Bottom- and
Top-references (1.2V and 3.2V) to get the full 16bit resolution for the pixels?
If not, how do I have to configure the AD9826 to have the best


Yes, it is possible to modify the reference voltage swing of the AD9826 (and
9814, 9822, 80066) by using an external reference. Please see the attached app
note as a recommendation- the op-amp in this note is a little old, and chosen
for low cost, so of course you could substitute a higher performance amp if you
wish. The main point is the CAPT and CAPB pins must be driven using a buffer,
they should not be connected directly the R-divider.