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Re: [10GMMF] TP3 Meeting minutes, November 23rd



re:
>         ACTION: Tom and Piers agreed to work towards closing
> off jitter on our Nov 30 call
...
>         4. TP3 Jitter testing   Tom L.
...
> Tom and Piers still working on pk-pk UI figure for high
> frequency test.

We have made progress.  We agree that most jitter is of kinds that we (in LRM) should not emulate by high probability Tx clock jitter.  We get different answers from different calculation methods.  Mandating an extremely small amount of SJ seems like complexity for little benefit.  We are now trying to choose between no added jitter and 0.05 UIpp.

An in-between approach that I haven't yet discussed with Tom would be to state in the narrative the RMS jitter we might expect a tester's clock to have (say ~2 ps RMS), and say that if a tester has an exceptionally good clock, one can consider dithering it.  This might improve consistency between testers.

Piers