[SI-LIST] layer stackup assignment

All,
For a 4-layer substrate package, if we assign the top layer
as signal layer, the second and third layer would be Power and Ground
planes.  We have VDD/VSS and AVDD/AVSS, so we have to split the second
and third layer for these two pairs of power and ground. 
 
It would have two options:
  Option 1. In second layer: two third of area as VDD, one third of area as 
AVSS, 
then in third layer:  two third of area underneath of VDD is assigned as VSS, 
the rest area -AVDD.

 Option 2.  In Second layer, two third of area as VSS, one third of area --AVDD,
 then third layer would be: two third of area underneath of VSS is assigned as 
VDD, the rest area --AVSS.

My question is:

Do both option work?  Which option is better than the other? 


Thanks,

Jie


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