FEDEVEL
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Mshakeri65 , 01-19-2018, 02:14 PM

Hi

For 12 layers PCB I have seen below stackup in different places and also at this fedevel link( https://www.fedevel.com/welldoneblog...clearance-via/ ):

• 12 Layers
  • L1 – Signal
  • L2 – GND
  • L3 – Signal
  • L4 – Signal
  • L5 – GND
  • L6 – Powers
  • L7 – Powers
  • L8 – GND
  • L9 – Signal
  • L10 – Signal
  • L11 – GND
  • L12 – Signal

the question is when we shield 2 adjacent signal layers (e.g. L3, L4) with 2 ground layers (e.g. L2, L5) the 2 internal signal layers will not have crosstalk (or any other EMC interferences) effect from each other when traces on one signal layer is routed in parallel way with another trace on second signal layer? When I checked the IMX6 PCB project I saw you shield all signal layers from each other with GND planes.
If I am going to use above stackup, should I follow a specific point in design (e.g. trace routing way on adjacent signal layers or prepreg or core thickness in stackup or ...)?
and at the end is there any priority for IMX6 stackup over above stackup?

Thanks.

robertferanec , 01-21-2018, 09:00 PM

They will. You need to be careful if you have two neighbor signal layers and if possible do not route tracks in parallel. Also, you may want to place thicker dielectricum between the signal layers and place the signal layers closer to the GND layers (use thinner dielectricum).

This link may help you more (the stackup which you attached doesnt have full specification):

Mshakeri65 , 01-25-2018, 12:14 AM

How much should I cost for a stackup with this specs for a quantity of 10pcs?

robertferanec , 01-25-2018, 10:59 AM

You will need to talk to your PCB manufacturer. There are many factors what influence PCB price. However, generally if you are using through hole only, then expect price around 500 - 1500USD, if you are planning to use uVIA it starts around 3,000USD and can go up to 10,000USD. A lot depends on size of your PCB.

You can also use the cheap websites to order PCB, but then you may not be able to control stackup and impedances.