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Re: Additional Patch for via properties dialog (2)

 

Oh I did not realize that gmail does not reply to the mailing list, but to
you directly.

I know how the progress of creating boards work. I know that you can only
have symmetrical stackups.
What I don't know is why KiCad limits micro-vias to outer to first inner
layer only.

To know where different via types can start and end, we have to be able to
either select start- and end-layer
arbitrarily for each via and keep it to the user to make sane decisions. Or
we have a dialog that can be
configured for the board that sets it globally.

The tricky thing with micro-vias is that you can have them stacked, or
staggered. When you have
them stacked you can go several layers deep. When you have them staggered
you can only move
one layer for each via and can not have one directly below.

Another option would be to allow micro-vias to be only one layer deep, but
make it possible to start on
inner layers. Right now I can only create one that connects the outer layer
to the one below it. That would
lead to multiple via elements put on-top of each other.

I am designing a board with this stackup:

so having arbitrarily selectable start- and end-layer is quite useful.

​The stackup I attached shows staggered vias on the outer 4 layers. For
stacked vias you can go through the 3
prepreg layers on each side of the board. But it is more expensive to
fabricate because the vias
have to be filled each run.

Cheers

2017-08-20 19:44 GMT+02:00 jp charras <jp.charras@xxxxxxxxxx>:

> Le 20/08/2017 à 17:12, Bastian Neumannn a écrit :
> > On the issue of layers and via types.
> >
> > The current system allows micro-vias from the outer to the underlying
> layer. blind and burried vias
> > from the second to the second-last layer and regular vias through all
> layers.
> > In my current design I have micro-vias going from the outer to the third
> and third-last layer
> > because I have three layers of sequential buildup.
> >
> > SIGANL
> > GND
> > SIGNAL
> > IN.4
> > IN.5
> > SIGNAL
> > SIGNAL/GND mixed
> > SIGNAL
> >
> > For now I decided to make start- and end-layers arbitrarily selectable.
> Maybe we should have a layer
> > stackup dialog that gives rules for that?
> >
> > Let it be a dialog with the three types and start- end layer for
> through, start end-layer for blind
> > burried and two start- end-layers for micro.
> >
> > What are your thoughts on that?
>
> First, please, *send your mails to the developers ML*.
>
> Before working on blind and buried vias dialog, please have a look at:
> https://www.eurocircuits.com/blog/Blind-and-buried-vias
>
> and like you can see, "make start- and end-layers arbitrarily selectable"
> is not a very good idea.
>
> >
> > 2017-08-19 16:47 GMT+02:00 jp charras <jp.charras@xxxxxxxxxx <mailto:
> jp.charras@xxxxxxxxxx>>:
> >
> >     Le 19/08/2017 à 15:20, Bastian Neumannn a écrit :
> >     > Ok so basically the dialog asking to change the sizes should come
> when you change the type in the
> >     > dialog, not when you press OK?
> >
> >     Changing the via type is more tricky:
> >     - One can use the net size as default when changing between micro
> vias and other types.
> >     - But the vias layers must also be set in any case. There are
> constraints on layers for each type.
> >
> >     Obviously, this dialog will need a bit of experiments.
> >
> >     >
> >     > And no dialog should come when the via is smaller than it's net
> class when pressing OK?
> >
> >     OK (only an error message the via is smaller than design settings)
> >
> >     >
> >     > Should be easy to implement it that way.
> >     >
> >     >
> >     > Cheers
> >     >
> >     > Am 19.08.2017 2:14 nachm. schrieb "jp charras" <
> jp.charras@xxxxxxxxxx <mailto:jp.charras@xxxxxxxxxx> <mailto:
> jp.charras@xxxxxxxxxx
> >     <mailto:jp.charras@xxxxxxxxxx>>>:
> >     >
> >     >     Le 19/08/2017 à 09:37, Bastian Neumannn a écrit :
> >     >     > Hi Jean-Pierre
> >     >     >
> >     >     > The other patch I submitted let's you change the via type.
> Changing from micro to through
> >     >     gives you
> >     >     > a through hole via that has the size of a micro via. This
> additional patch warns the user if that
> >     >     > ist the case.
> >     >
> >     >     I understand.
> >     >
> >     >     However I still am thinking:
> >     >     1 - using a via/track size smaller than its net class value is
> a very frequent case
> >     >     2 - If changing from micro to through ( or the opposite) gives
> you a through hole via that has the
> >     >     size of a micro via (or the opposite) (or do not correctly
> update the layers) means the dialog in
> >     >     badly designed.
> >     >
> >     >     >
> >     >     > Cheers
> >     >     >
> >     >     > Am 19.08.2017 8:23 vorm. schrieb "jp charras" <
> jp.charras@xxxxxxxxxx <mailto:jp.charras@xxxxxxxxxx>
> >     >     <mailto:jp.charras@xxxxxxxxxx <mailto:jp.charras@xxxxxxxxxx>>
> >     <mailto:jp.charras@xxxxxxxxxx <mailto:jp.charras@xxxxxxxxxx>
> <mailto:jp.charras@xxxxxxxxxx
> >     <mailto:jp.charras@xxxxxxxxxx>>>>:
> >     >     >
> >     >     >     Le 18/08/2017 à 20:47, Bastian Neumannn a écrit :
> >     >     >     > Hi,
> >     >     >     >
> >     >     >     > the last patch for this function was not correct I am
> sorry. This patch gives the correct
> >     >     >     > functionality to notify the user when die via size is
> smaller than the minimum size given in
> >     >     >     the net
> >     >     >     > class.
> >     >     >     >
> >     >     >     > Cheers
> >     >     >     >
> >     >     >
> >     >     >     Hi Bastian,
> >     >     >
> >     >     >     I don't really understand your patch:
> >     >     >
> >     >     >     the only one DRC error is when a via/track size is
> smaller than the minimal via/track size
> >     >     given in
> >     >     >     design settings, that does not depend on the net class.
> >     >     >
> >     >     >     using a via/track size smaller than its net class value
> is a very frequent case.
> >     >     >
> >     >     >     --
> >     >     >     Jean-Pierre CHARRAS
> >     >     >
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> >     >     Jean-Pierre CHARRAS
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> >     Jean-Pierre CHARRAS
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> --
> Jean-Pierre CHARRAS
>

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