External Memory Interfaces Stratix® 10 FPGA IP User Guide

ID 683741
Date 4/01/2024
Public
Document Table of Contents

11.1.1.2.4. DQS Gating / Postamble

Postamble timing is a setup period during which the DQS signal goes low after all the DQ data has been received from the memory device during a read operation. After postamble time, the DQS signal returns from a low-impedance to a high-impedance state to disable DQS and disallow any glitches from writing false data over valid data.

The Timing Analyzer analyzes the postamble timing path in DDRx memory protocols only through an equation which considers memory calibration, calibration uncertainty, and tracking uncertainties as shown in the following figure.

Figure 91. DQS Gating Timing Analysis

DQS Gating timing analysis