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nicola67761 , 08-24-2016, 01:56 AM

hi All
I have 2 question about Lession 3 and 4 of Advance PCB Laytout.
1 - If i ask a stackUP document from PCB manufacturer, what i have to send them about information?
So, how they can generate that document?
2 - About data ram signal, i thinked to route every data block without matching length.
In second time, redraw every tracks with the same length of too longer track found, is correct?
Thanks

mairomaster , 08-24-2016, 07:01 AM

1. The more information, the better. Things to consider:

- General information about the board.
- Layer count.
- Type of the different layers - signal, power, planes.
- For the signal layers, do you have controlled impedance signals on a particular layer and what is the impedance supposed to be. You might have a few different impedances on a single layer as well - for example single ended 50 ohm, differential 100 ohm, differential 90 ohm, etc.
- What types of vias do you need - do you need blind/buried/micro vias and between which layers.
- Estimation of what constrains you need - track width/gap on particular layers, via sized, etc. Of course the final track geometry will be provided with the manufacturer's stack.
- Anything else that could be useful.

2. This strategy sounds alright to me.

robertferanec , 08-24-2016, 06:05 PM

Hello @nicola67761.

1) This may help you: How to design PCB stackup

2) yes, this is one of the ways how you can do it. Many times I do it the way, the I found the shortest track one and I try to make it as long as the longest is. If that is not possible, I do it as long as possible and find another shortest track. I repeat this until all the tracks are the same length.

nicola67761 , 08-27-2016, 03:34 AM

thank you very much, maiormaster and Robert
i will try to do this with my pcb manufacturer.