In my first high-speed PCB design, I have an LPDDR3 RAM and my PCB have 6 layers with the below sequence:
the region between the SOC and RAM is totally covered by VCC-DRAM in the VCC_Plane layer. Considering all requirements of impedance controlling of all layers is truly fulfilled, My questions are:
Could I route my tracks in any of signal layers? aren't there any differences between referencing my tracks to GND or VCC?
Is there any special signal group for example differential pairs or data groups that I should exactly reference them to GND(routing only in layer 1 and 3) or to VCC(routing only in layer 4 and 6)?
If there isn't any difference between them, what is the fact behind that which makes VCC plane and GND plane behave the same in referencing signals?