Visible to Intel only — GUID: hco1416491440891
Ixiasoft
Visible to Intel only — GUID: hco1416491440891
Ixiasoft
7.2.4.1. Setup and Hold Derating for UniPHY IP
For RDIMMs, the slew rate is defined at the register on the RDIMM, instead of at the memory component. For LRDIMMs, the slew rate is defined at the buffer on the LRDIMM, instead of at the memory component.
The following table lists the setup and hold derating parameters.
Parameter |
Description |
---|---|
LPDDR2/DDR2/DDR3 SDRAM/RLDRAM 3 |
|
Derating method |
Derating method. The default settings are based on Intel® internal board simulation data. To obtain accurate timing analysis according to the condition of your board, Intel recommends that you perform board simulation and enter the slew rate in the Quartus Prime software to calculate the derated setup and hold time automatically or enter the derated setup and hold time directly. For more information, refer to the “Timing Deration Methodology for Multiple Chip Select DDR2 and DDR3 SDRAM Designs” section in the Analyzing Timing of Memory IP chapter. |
CK/CK# slew rate (differential) |
CK/CK# slew rate (differential). |
Address/Command slew rate |
Address and command slew rate. |
DQS/DQS# slew rate (Differential) |
DQS and DQS# slew rate (differential). |
DQ slew rate |
DQ slew rate. |
tIS |
Address/command setup time to CK. |
tIH |
Address/command hold time from CK. |
tDS |
Data setup time to DQS. |
tDH |
Data hold time from DQS. |
RLDRAM II |
|
tAS Vref to CK/CK# Crossing |
For a given address/command and CK/CK# slew rate, the memory device data sheet provides a corresponding "tAS Vref to CK/CK# Crossing" value that can be used to determine the derated address/command setup time. |
tAS VIH MIN to CK/CK# Crossing |
For a given address/command and CK/CK# slew rate, the memory device data sheet provides a corresponding "tAS VIH MIN to CK/CK# Crossing" value that can be used to determine the derated address/command setup time. |
tAH CK/CK# Crossing to Vref |
For a given address/command and CK/CK# slew rate, the memory device data sheet provides a corresponding "tAH CK/CK# Crossing to Vref" value that can be used to determine the derated address/command hold time. |
tAH CK/CK# Crossing to VIH MIN |
For a given address/command and CK/CK# slew rate, the memory device data sheet provides a corresponding "tAH CK/CK# Crossing to VIH MIN" value that can be used to determine the derated address/command hold time. |
tDS Vref to CK/CK# Crossing |
For a given data and DK/DK# slew rate, the memory device data sheet provides a corresponding "tDS Vref to CK/CK# Crossing" value that can be used to determine the derated data setup time. |
tDS VIH MIN to CK/CK# Crossing |
For a given data and DK/DK# slew rate, the memory device data sheet provides a corresponding "tDS VIH MIN to CK/CK# Crossing" value that can be used to determine the derated data setup time. |
tDH CK/CK# Crossing to Vref |
For a given data and DK/DK# slew rate, the memory device data sheet provides a corresponding "tDH CK/CK# Crossing to Vref" value that can be used to determine the derated data hold time. |
tDH CK/CK# Crossing to VIH MIN |
For a given data and DK/DK# slew rate, the memory device data sheet provides a corresponding "tDH CK/CK# Crossing to VIH MIN" value that can be used to determine the derated data hold time. |
Derated tAS |
The derated address/command setup time is calculated automatically from the "tAS", the "tAS Vref to CK/CK# Crossing", and the "tAS VIH MIN to CK/CK# Crossing" parameters. |
Derated tAH |
The derated address/command hold time is calculated automatically from the "tAH", the "tAH CK/CK# Crossing to Vref", and the "tAH CK/CK# Crossing to VIH MIN" parameters. |
Derated tDS |
The derated data setup time is calculated automatically from the "tDS", the "tDS Vref to CK/CK# Crossing", and the "tDS VIH MIN to CK/CK# Crossing" parameters. |
Derated tDH |
The derated data hold time is calculated automatically from the "tDH", the "tDH CK/CK# Crossing to Vref", and the "tDH CK/CK# Crossing to VIH MIN" parameters. |