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iMX7D: Simulating LPDDR3 with Hyperlynx

Question asked by Noelia Scotti on Aug 4, 2017
Latest reply on Aug 9, 2017 by Yuri Muhin

I am doing pre-layout simulation in order to start the PCB design, but I have doubts.
1. I don't find the recommended trace impedance for the LPDDR3 memory in the hardware development guide. The recommended value is only for DDR3 memory, not for LPDDR3. Micron recommends 60 ohm for single ended and 120 ohm for differential pairs. Which value is the correct impedance for LPDDR3 memory?
2. The iMX7 IBIS model doesn't have the Diff pin section, it is a problem for the DDR simulation. Do you have a complete model? We added the diff pin section manually but I don't know if it is fine. I don't know the vdiff value.

[Diff Pin] inv_pin vdiff tdelay_typ tdelay_min tdelay_max
AF25 AE25 0.000V 0.000s NA NA
AG23 AG24 0.000V 0.000s NA NA
AC20 AB20 0.000V 0.000s NA NA
AD27 AC27 0.000V 0.000s NA NA
Y24 Y23 0.000V 0.000s NA NA