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

Stratix 10 Transceiver IP Data rate - CDR ref clock relation

Hi,

What is the mathematical relationship between the transceiver PHY data rate and CDR reference clock frequency.

When I specify the data rate in the PHY IP,In RX-PMA tab for CDR reference clock frequency it lists the permissible CDR ref clocks.

I would like to know this relation.

Is there a way to know the supported data rates for a particular CDR reference clock frequency?

1 Reply

  • CheepinC_altera's avatar
    CheepinC_altera
    Icon for Regular Contributor rankRegular Contributor
    6 years ago

    Hi,

    As I understand it, you would like to ask about the data rate and CDR refclk. It is recommended for you to use the Native PHY, set your target data rate and then you will find the supported refclk frequency for that data rate under the drop down list. There is no specific equation available in the documentation to relate the refclk and data rate. However, as I understand it at high level, there are a number of counters and blocks in between which determine the supported values. Those values under the drop down list are verified valid by Factory.