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DS80PCI810: redriver is not working

Part Number: DS80PCI810

Hi Experts,


we have used the two redriver on the path & it is not working, eye is always closed at 8Gbps when we run PRBS31

Test method/channel:  FPGA --> Redriver --> Redriver  --> looped back. 

FYI : tested with 1G, It worked & 8Gbps is working at PRBS7 (with small eye opening) .

We have tried fine tuning the equalizer, But it didn't help to solve the issues.


As per our test method, 4 times redriver used in the path, Will  redriver (DS80PCI810NJYR) suggest to use 4 times. 


Please provide your advice 



  • Hi Karthik,

    We typically recommend a single redriver in the signal path. Having more redriver in the signal path makes it hard to fine tune the EQ settings. 

    I am not sure if this is possible but you can put scope at the output of the first redriver and optimize EQ settings. Then using this EQ setting optimize the second redriver.

    However, this also depends on the how much loss you have between these two redrivers. I suppose the more loss the better.

    Given PRBS7 seems to work better than PRBS31, you may want to increase value of your AC coupling Cap to see if you note any improvement.


  • Hi Nasser,

    Thank you for the updates.

    We will try and update you.