GTS Transceiver PHY User Guide

ID 817660
Date 4/01/2024
Public
Document Table of Contents

3.6.2. Recommended tx/rx_coreclkin Connection and tx/rx_clkout2 Source

Recommended Connection and Source table below shows recommended i_tx/rx_coreclkin connection and o_tx/rx_clkout and o_tx/rx_clkout2 source, based on the datapath clocking mode and double-width transfer selection.

Table 39.  Recommended Connection and Source
Datapath Clocking Mode Core Interface FIFO Mode Enable TX/RX Double Width Transfer Recommended tx/rx_coreclkin connection Recommended tx/rx_clkout or tx/rx_clkout2 source Division factor
PMA Phase Compensation No o_tx/rx_clkout Word clock N/A
Yes o_tx/rx_clkout2 Word clock 2
Elastic Yes o_tx/rx_clkout2 or any other clock source from user Word clock/User clock 2
No o_tx/rx_clkout or any other clock source from user Word clock/User clock N/A
System PLL Phase Compensation No o_tx/rx_clkout Sys PLL clock N/A
Yes o_tx/rx_clkout Sys PLL clock 2
  • When using system PLL clocking mode, both o_tx_clkout and o_rx_clkout can clock i_tx_coreclkin and i_rx_coreclkin.
  • When using PMA clocking mode, o_tx_clkout/2 must clock i_tx_coreclkin. o_rx_clkout/2 must clock i_rx_coreclkin. The only exception to this requirement in PMA clocking mode is for chip to chip applications where TX and RX share same reference clock source (that is, 0 PPM difference), o_tx_clkout or o_rx_clkout can clock both i_tx_coreclkin and i_rx_coreclkin.