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RPett4's avatar
RPett4
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

Arria 10 SX LVDS SERDES with global clocks?

I am trying to determine if a certain FMC ADC board is compatible with a 3rd party Arria 10 SX FMC carrier card, transceiver speed grade 2, fpga fabric speed grade -1. The ADC board has 4 source synchronous serial LVDS interfaces, so 4 clock pairs and 4 data pairs. The serial clock rate is 600 MHz. Unfortunately the clocks are not being routed to any of the regional clock capable pins (*_CC) of the Arria 10. The Arria 10 handbook seems to indicate that you can promote a non-dedicated clock pin to a global clock:

"Intel recommends providing the I/O PLL reference clock using a dedicated pin when possible. If you want to use a non-dedicated pin for the PLL reference clock, you have to explicitly promote the clock to a global signal in the Intel Quartus Prime software. "

Does this mean it is possible to operate the LVDS SERDES using the ADC clocks, promoted to a global pin?

Could this method work, or is there a different way to interface with this serial stream?

9 Replies

  • Rahul_S_Intel1's avatar
    Rahul_S_Intel1
    Icon for Frequent Contributor rankFrequent Contributor

    Hi,

    I would strongly recommend to use a dedicated clock pin , if you are using Altera LVDS IP , other wise you may encounter some fitter issues when using Altera LVDS IP.

    • RPett4's avatar
      RPett4
      Icon for Occasional Contributor rankOccasional Contributor

      The boards are already designed so I can't move the pins. If I promote the pin to a global clock, use that for the SERDES, and the design still meets timing, will it work or not?

  • Rahul_S_Intel1's avatar
    Rahul_S_Intel1
    Icon for Frequent Contributor rankFrequent Contributor

    Hi,

    Hope the issue is resolved with solution provided in the private message

    • RPett4's avatar
      RPett4
      Icon for Occasional Contributor rankOccasional Contributor

      I have not seen a private message related to this issue. Can you resend?

    • RPett4's avatar
      RPett4
      Icon for Occasional Contributor rankOccasional Contributor

      Yes, thank you I have now received the private message. I will try what you suggest.