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  4. AR# 59035: Design Advisory for 7 Series FPGA GTX/GTH Transceivers - QPLL not supported for PCIe Gen1/Gen2

AR# 59035

Design Advisory for 7 Series FPGA GTX/GTH Transceivers - QPLL not supported for PCIe Gen1/Gen2

Description

This Design Advisory covers the recommended PLL usage for PCI Express Gen1 and Gen2 rates in the 7 series FPGA GTX/GTH Transceiver.

Solution

The 7 Series FPGA GTX/GTH Transceivers User Guide v1.9.1 (UG476) or earlier revisions indicate that both CPLL and QPLL can be used for PCI Express Gen1 and Gen2 rates.

However, the PCIe Gen1 and Gen2 solution was only tested and validated using the CPLL. 

Using QPLL in PCIe Gen1 and Gen2 mode is not supported. 

The 7 Series FPGA GTX/GTH Transceivers User Guide is updated in the next revision v1.10 to reflect this.

Note: The above recommendation does not affect Xilinx 7 series Integrated Block for PCI Express core as it supports CPLL only.

Linked Answer Records

Master Answer Records

Answer Number Answer Title Version Found Version Resolved
42944 Design Advisory Master Answer Record for Virtex-7 FPGA N/A N/A
42946 Design Advisory Master Answer Record for Kintex-7 FPGA N/A N/A
AR# 59035
Date 09/12/2014
Status Active
Type Design Advisory
Devices