Inputs required for the PCB Manufacturer to provide a stackup

[hioyo]

Dear Team,

I a building a board which is 4 layers(SIGNAL-GND-PWR-SIGNAL).

The layout is finished and I need to get the stack up from the Manufacturer.

My question is what are the inputs I need to provide the PCB manufacturer to get a
stack up for a 4 layer board.

Regards
HARI

 

[FlyingDutch]

Dear Team,

I a building a board which is 4 layers(SIGNAL-GND-PWR-SIGNAL).

The layout is finished and I need to get the stack up from the Manufacturer.

My question is what are the inputs I need to provide the PCB manufacturer to get a
stack up for a 4 layer board.

Regards
HARI

Hello,

you have to generate "Gerber" files for your project from CAD you used for doing the PCB. The "Gerber files, are standard use by PCB manufacturers (them are also used to import PCB projects between many CAD's software).

Best Regards

--- Updated Mar 12, 2022 ---

Hello,

you have to generate "Gerber" files for your project from CAD you used for doing the PCB. The "Gerber files, are standard use by PCB manufacturers (them are also used to import PCB projects between many CAD's software).

Best Regards

BTW: in many cases also BOM file (Bill of material) is used.

Regards

 

[hioyo]

Thank you...

PCB thickness and Copper thickness are given by the fabricator . Please correct me if I am wrong

 

[FvM]

PCB can be manufactured in a wide range of substrate thickness and copper weight, using different materials and surface finish. The choice is driven by application requirements.

You didn't yet mention specific requirements, did you consider using a default manufacturer stackup?

 

[hioyo]

PCB can be manufactured in a wide range of substrate thickness and copper weight, using different materials and surface finish. The choice is driven by application requirements.

You didn't yet mention specific requirements, did you consider using a default manufacturer stackup?

Mine is a simple board.
No controlled impedance traces.
99% are analog only

Only one digital interface is there.The only constraint is the maximum
capacitance on the digital data line should be less than 15pf

 

[FvM]

Simple 4-layer stackups vary in thickness of the outer prepregs. Low capacitance suggests to choose thinner core and thicker prepregs, like below

 

[betwixt]

Gerbers should be all you need, the layers will be identified by the Gerber filename and assuming the design was done on a decent CAD package, all the X-Y references should line up between layers. If in doubt, add an alignment marker to the same spot on all layers.

Normally, the fabrication plant will pick the layer thickness unless you specifically ask for non-standard construction.

Brian.

 

[marce]

4 layers standard basic board is often based on a 1mm core with approx 0.25mm pre-pregs with foil outers...

 

[hioyo]

4 layers standard basic board is often based on a 1mm core with approx 0.25mm pre-pregs with foil outers...

If we have different controlled impedance traces lets say 90 ohm,120ohm..may I know how to approach

 

[barry]

If we have different controlled impedance traces lets say 90 ohm,120ohm..may I know how to approach

1) you specify layer thicknesses/stack up, trace dimensions
2) you use mfr’s standard stackup, you specify trace dimensions

either way, you specify trace impedances and manufacturer will adjust things on their end to meet those requirements.

 

[marce]

You need a stack up, to determine the dimensions of the diff pairs to achieve the desired impedance. You also need to have an adjacent return plane for the controlled impedance signals. You will need Saturn PCB toolkit or similar for the calculations...
Most Importantly you need.
A PCB stack up with dimensions and Er of the pre-pregs/cores, you cannot even start a design without that information is using diff pairs...