External Memory Interface Handbook Volume 2: Design Guidelines: For UniPHY-based Device Families
2.3.1. Terminations for Single-Rank DDR3 SDRAM Unbuffered DIMM
The following table lists the recommended termination and drive strength setting for UDIMM and Stratix III, Stratix IV, and Stratix V FPGA devices.
|   Signal Type  |  
         SSTL 15 I/O Standard (1)  |  
         FPGA End On-Board Termination (2)  |  
         Memory End Termination for Write  |  
         Memory Driver Strength for Read  |  
      
|---|---|---|---|---|
|   DQ  |  
         Class I R50C/G50C (3)  |  
         —  |  
         60-ohm ODT (4)  |  
         40-ohm (4)  |  
      
|   DQS  |  
         Differential Class I R50C/G50C (3)  |  
         —  |  
         60-ohm ODT (4)  |  
         40-ohm (4)  |  
      
|   DM  |  
         Class I R50C (3)  |  
         —  |  
         60-ohm ODT (4)  |  
         40-ohm (4)  |  
      
|   Address and Command  |  
         Class I with maximum drive strength  |  
         —  |  
         39-ohm on-board termination to VDD (5)  |  
      |
|   CK/CK#  |  
         Differential Class I R50C  |  
         —  |  
         On-board (5) 2.2 pf compensation cap before the first component; 36-ohm termination to VDD for each arm (72-ohm differential); add 0.1 uF just before VDD.  |  
      |
|   Notes to Table: 
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You can implement a DDR3 SDRAM UDIMM interface in several permutations, such as single DIMM or multiple DIMMs, using either single-ranked or dual‑ranked UDIMMs. In addition to the UDIMM’s form factor, these termination recommendations are also valid for small‑outline (SO) DIMMs and MicroDIMMs.