Hi! I bought two AD676. The first one is supposed to be an original, it shipped from the US. But the second IC I bought on eBay from China, it costs more than three times cheaper. I haven't tested it yet since I would like to explore the difference…
People want faster, more bits, and smaller packages, so more and more ADCs are serial. However,
you could look at the AD676, AD1674, or AD7880. If you want an AD574, you will have to buy
the 5962xxxx full mil part.