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

ID 683385
Date 3/06/2023
Document Table of Contents
Give Feedback Write to Memory in Slot 1 Using an ODT Setting of 75-ohm

The following figure shows the double parallel termination scheme (Class II) using ODT on the memory with the memory-side series resistor when the FPGA is writing to the memory using a 25-ohm OCT drive strength setting on the FPGA. In this scenario, the FPGA is writing to the memory in slot 1 and the ODT feature of the memory at slot 2 is turned on.
Figure 36. Double Parallel Termination Scheme (Class II) Using ODT on DDR2 SDRAM DIMM with a Memory-Side Series Resistor