Hi Dan and thanks again for your message, Yes you are right, my bad. The devices i am thinking of driving are a second ADS4225 as the target DSO is a quad channel. Also i want to drive that clock to the FPGA off course which will process the ADC data. The solution you are suggesting regarding the clock would be great if i was driving only one device. Would there be a chance to accomplish that (driving multiple devices from LMK61PD0A2) by using low noise high bandwidth opamps to distribute the signal across many devices or just use (better i think) a solution like the clock i have suggested BUT with better jitter performance? There is actually a formula that dictates the max jitter allowable for an ADC based on resolution (number of bits) and input signal frequency: This off course becomes, as follows, if the numerator is 1 or the input signal is just full scale: As i read, this formula calculates the value of jitter that will result in no more than 1/2 LSB (N+1) noise for the given params which are N=12bits & Fin=100MHz. The calculated value (max allowable jitter) was 389fs. Now if i solve for Fin=50MHz the max allowable jitter gets double the previous one: 777fs. What do you think? So, thinking that the clock i suggested has a 300fS which if combined with the ADC aperture jitter (140fS) gives me a total of 331fs => sqrt( CLKjiter^2 + APERTUREjitter^2) means that i am close to my target for 100MHz or 2 times lower for Fin=50MHz.. Does TI have a similar clock solution so that i can feed at least 4 devices with the clock signal? I know that given the length of the signal traces they are considered as "transmission lines" and must be terminated accordingly. I know for a fact that in practice values will be a little worse and that is why the clock should be a little better than 300fs (for 100MHz). Can you pls suggest if i am doing this wrong? The truth is that i have been working as an engineer for 20 years but regarding high speed signalling and high speed ADCs, my experience is not that good. Please be kind to revert with any suggestions you might have. Regards Manos
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