NVDIMM Pull-up Resistor Recommendation

By Colby Parkinson - 2017-08-17

JEDEC specifies that the pull-up resistor for the SAVE_N pin on NVDIMMs belongs on the motherboard.

Micron designs NVDIMM with and without the pull-up resistor to support all customers, since some current motherboards do not include the SAVE_N pull-up resistor.  However, we believe this recent specification pushes NVDIMM architecture in the right direction, because it eliminates ambiguity.  

Diagram of JEDEC Specification
Diagram of JEDEC Specification (click to enlarge)

Placing the pull-up resistor on the motherboard allows that resistor to be tuned to the specific SAVE_N load of each design.  This gives customers the flexibility to develop their systems for their specific requirements.  

Micron recommends customers place the SAVE_N pull-up resistor on the motherboard for all future designs and follow JEDEC specification.

Colby Parkinson