External Memory Interface Handbook Volume 2: Design Guidelines: For UniPHY-based Device Families

ID 683385
Date 3/06/2023
Public
Document Table of Contents

9.11.2.1. Slew Rates

You can obtain the slew rates in one of the following ways:
  • Intel performs PCB simulations on internal Intel boards to compute the output slew rate and ISI effects of various multiple chip select configurations. These simulation numbers are prepopulated in the Slew Rates based on the number of ranks selected. The address and command setup and hold times (tDS, tDH, tIS, tIH) are then computed from the slew rate values and the baseline nonderated tDS, tDH, tIS, tIH numbers entered in the Preset Editor. The parameter editor shows the computed values in Slew Rates. If you do not have access to a simulator to obtain accurate slew rates for your specific system, Intel recommends that you use these prepopulated numbers for an approximate estimate of your actual board parameters.
  • Alternatively, you can update these default values, if dedicated board simulation results are available for the slew rates. Custom slew rates cause the tDS, tDH, tIS, tIH values to be updated. Intel recommends performing board level simulations to calculate the slew rate numbers that accounts for accurate board-level effects for your board.
  • You can modify the auto-calculated tDS, tDH, tIS, tIH values with more accurate dedicated results direct from the vendor data sheets, if available.