AnsweredAssumed Answered

AD9234 coplanar ground

Question asked by yka Employee on Jul 21, 2016
Latest reply on Jul 25, 2016 by UmeshJ

Customer is asking the following question. Please share your experience :

"We are trying to find a reliable way to manage signal Gnd return between a very wide bandwidth T & H and AD9234, through use of Grounded CPWs.  AD9234 has Pwr-S-S-Pwr arrangement of input lines, where we usually rely on Gnd-S-S-Gnd to preserve signal integrity at high frequency.  ADI’s pin arrangement can be more problematic if the source signal is delivered by a part with VDD that is different from 3.3V on AD9234 – Pwr and Gnd are both AC-ground and Pwr can be used for high-frequency ground return, but when AC-ground at one line end is at a different potential than at the at the other line end, we cannot easily preserve a uniform low-resistance return path for the sampled signal.  A non-uniform Gnd return induces signal distortion. 

   Has ADI investigated this issue at all, and if so, what is the recommended way to preserve signal ground return?"