12 layer stackup recommendation

[Rapport]

I would like to design a 12 layer stackup. Please suggest whether below mentioned is good one to follow.

Top
GND
Signal
Signal
GND
Power
Power
GND
Signal
Signal
GND
Bottom

When I searched browsed I found the below stackup but it has more than 4 signal layers. I need only 4 signal layers to use within 12 layer.
Top
GND
Signal
Signal
GND
Signal
Signal
GND
Signal
Signal
power
Bottom

 

[jayakrishnanj]

Is it Analog or Digital Board?

My suggestion

If Analog

TOP
GND
SIG
PWR
GND
SIG
SIG
GND
PWR
SIG
GND
BOT

If Digital

TOP
GND
SIG
PWR
GND
SIG
SIG
PWR
GND
SIG
PWR
BOT

 

[marce]

And what if its analogue and digital....
Both analogue and digital signals travel the same way across a PCB (there are differences in return paths related to frequency) but digital signals are effectively analogue signals at this level. Without knowing the full design specification, board area, how it roughly places, types of signals, speed of signals etc all anyone can do is guess....

 

[jayakrishnanj]

Marce, Yes you are right,

I guessed it from Rapports layer stack up, I saw his layer stack up required solid ground return for all the signals,

we should know the type of Design, signal Frequency, etc

I felt my stack up was more generic, may be I am wrong.

 

[marce]

I agree with a return layer for each signal layer, this could be either GND or a Power layer (preferably GND), the problem with power layers is they are often split so are not suitable for a return plane. Ass to the mix that really you also want each power layer paired closely with a GND plane to get some planar capacitance (the more the better) as you first point of supply decoupling (or keeping the supply inductance low at the desired frequency of operation, or supply decoupling as it is simply called).
The best compromise often is to have specific layers for the critical signals (these must have a solid contiguous return plane adjacent to them) and have some signal layers for non critical signals.