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- I even saw a couple of applications where digital FPGA pins (actually a LVDS receiver and a LVTTL output) were used to implement A/D conversion, through an external RC. Anyway this is a non conventional design and I don't think it leads to a straightforward implementation.
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Hallo,
what you mean is a simple Sigma-Delta ADC like this
http://www.altera.com/support/examples/dsp-builder/exm-sigma-delta-converter.html?gsa_pos=1&wt.oss_r=1&wt.oss=sigma .
There are several examples for those ADCs on web, but they are not easy to understand!
Greets