Intel® Cyclone® 10 GX Transceiver PHY User Guide

ID 683054
Date 4/14/2023
Public
Document Table of Contents

3.9.4. Skew Calculations

To calculate the maximum skew between the channels, the following parameters are used:

  • PMA to PCS datapath interface width (S)
  • Maximum difference in number of parallel clock cycles between deassertion of each channel's FIFO reset (N)

To calculate the channel skew, the following scenarios are considered:

  • Non-bonded

    In this case, both the PMA and PCS are non-bonded. Skew ranges from 0 UI to [(S-1) + N*S] UI.

  • PMA bonding using x6 / xN clock network

    In this case, the PCS is non-bonded. Skew ranges from [0 to (N*S)] UI + x6/xN clock skew.

  • PMA bonding using the PLL feedback compensation clock network

    In this case, the PCS is non-bonded. Skew ranges from [0 to (N*S)] UI + (reference clock skew) + (x6 clock skew).

  • PMA and PCS bonding using the x6 / xN clock network

    Skew = x6 / xN clock skew.

  • PMA and PCS bonding using PLL feedback compensation clock network

    Skew = (reference clock skew) + (x6 clock skew).