External Memory Interface Handbook Volume 3: Reference Material: For UniPHY-based Device Families

ID 683841
Date 3/06/2023
Public
Document Table of Contents

1.17. UniPHY Calibration Stages

The DDR2, DDR3, and LPDDR2 SDRAM controllers with UniPHY Intel FPGA IP, the QDR II and QDR II+ SRAM Controller with UniPHY Intel FPGA IP, the RLDRAM II Controller with UniPHY Intel FPGA IP, and the RLDRAM 3 UniPHY Intel FPGA IP, go through several stages of calibration. Calibration information is useful in debugging calibration failures.

The section includes an overview of calibration, explanation of the calibration stages, and a list of generated calibration signals. The information in this section applies only to the Nios® II-based sequencer used in the DDR2, DDR3, and LPDDR2 SDRAM Controllers with UniPHY versions 10.0 and later, and, optionally, in the QDR II and QDR II+ SRAM and RLDRAM II Controllers with UniPHY version 11.0 and later, and the RLDRAM 3 PHY-only IP. The information in this section applies to the Arria II GZ, Arria V, Arria V GZ, Cyclone V, Stratix III, Stratix IV, and Stratix V device families.

Note:
  1. For QDR II and QDR II+ SRAM and RLDRAM II Controllers with UniPHY version 11.0 and later, you have the option to select either the RTL-based sequencer or the Nios II‑based sequencer. Generally, choose the RTL-based sequencer when area is the major consideration, and choose the Nios II-based sequencer when performance is the major consideration.
  2. For RLDRAM 3, write leveling is not performed. The sequencer does not attempt to optimize margin for the tCKDK timing requirement.