DS160PT801: Intra Pair Skew, and Inter-Pair Skew

Hi Roger,

Please refrain from discussing secure documentation on E2E public forums. I have removed comments regarding secure information.

Specified intra-pair skew is the maximum tolerated at each datarate.

Best,

David

Thank you David, sorry -i did not realize this was an issue on this forum.

i need to specify a cable assembly, where do i get the numbers from? i don't find them in the data sheet.  thanks

Hi Roger,

Do you have a model available of your cable assembly? From my understanding, your concern is with intra-pair skew (not inter-pair skew), correct? We have an IBIS-AMI model available if you'd like to model your current cable assembly with the retimer.

Best,

David

hi David

no i am hoping to start with a specification to give to Rosenberger.  It would be good to know what is the maximum skew the phy can tolerate intra pair. so as to get a head start.  I am asking them for data.  Now i have two technologies one is PCIE Gen 4 and one is 100GE. 100GE is very common out there.

you can see in the spec of the 100GE for instance what the number is 10ps/m ( let us assume this is close to what i will get ) 

AmphenolFCI-ca_qsfp_copper-datasheet.pdf (mouser.com)

so can the part do 10ps /m or better?

thanks

roger

h iDavid

would an S-parameter set help you do the simulation? i can ask the vendor's permission to allow me to share the 5 meter s-parameter (4 ports)

trouble is one measurment is not statistically significant.  I woner if we can crate a lab experiment where we introduce skew at fine steps to measure tolerance .  trouble is with psec kinda numbers, breathing on the board, and the temp in lab and.... affects it all.

thanks