I would like to use the Arty, but I need more differential pairs than are available through the high speed PMOD connectors.There are other differential pairs available, but I don't know how they are routed and what the trace lengths are. Is this information available anywhere? As an example, JA2 and JA3 are two signals of a diff pair. I could change R5 and R9 to zero ohms, so that is no problem. The next question is are the traces the correct impedance? They will be if they are on the same layer and use the same trace width as the signals to PMOD connector JB which is presumably standard 100 ohm LVDS. If that all turns out to be true, then all I need is the trace lengths and I will be able to match them by using the correct lengths on my daughter board to make up any difference.

So the question, is there any PCB data available that I could use to determine the answers to these questions?

I would like to use the Arty, but I need more differential pairs than are available through the high speed PMOD connectors.There are other differential pairs available, but I don't know how they are routed and what the trace lengths are. Is this information available anywhere? As an example, JA2 and JA3 are two signals of a diff pair. I could change R5 and R9 to zero ohms, so that is no problem. The next question is are the traces the correct impedance? They will be if they are on the same layer and use the same trace width as the signals to PMOD connector JB which is presumably standard 100 ohm LVDS. If that all turns out to be true, then all I need is the trace lengths and I will be able to match them by using the correct lengths on my daughter board to make up any difference.

So the question, is there any PCB data available that I could use to determine the answers to these questions?

Thanks

Dave Miller

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