Analog to digital converter confustion

[Kevin Sevcik]

Originally Posted by Adam Y.

The ability to measure 5 volts and 20MSPS are the only requirments I really care about. I'm pretty sure that Im botching something up or looking at the wrong specification because I can find the 20MSPS but I can't find the five volts. Im assuming that 2Vp-p means 2 volts peak to peak. Im even apt to using a DSP.

Unfortunately, that's a pretty extreme specification and I don't think you're likely to find anything that will meet both of those at the same time. You'll probably have to relax one of those requirements to get a chip you can work with. If you really absolutely have to measure signals in the 10MHz range for some reason, then I think your best bet is to run your signal through a high bandwidth op-amp first with a gain of .5 or some such so you can look for ADCs with a smaller input range. I'm pretty certain that even switching to a DSP won't help, as the faster DSPs tend to need 3.33V supplies or less.