External Memory Interfaces Agilex™ 7 F-Series and I-Series FPGA IP User Guide

ID 683216
Date 9/19/2024
Public
Document Table of Contents

11.5.5. Operate at a Lower Speed

Test the interface at a lower speed. If the interface works at a lower speed, the interface is correctly pinned out and functional.

If the interface fails at a lower speed, determine if the test is valid. Many high-speed memory components have a minimal operating frequency, or require subtly different configurations when operating at a lower speeds.

For example, DDR4 SDRAM typically requires modification to the following parameters if you want to operate the interface at lower speeds:

  • tMRD
  • tWTR
  • CAS latency and CAS write latency