Allow an odd layer number / asymmetric stackups (lp:#1829379)

changed weight to 14

added pcbnew prioritywishlist statusconfirmed labels

Wayne Stambaugh (stambaughw) wrote:

The other option would be to use the old standby method of creating a four
layer board and not adding anything to one of the inner two layers.  Of
course you have have to be careful not to route on the unused layer and to
send the correct inner layer to have your boards made.  It's not very
elegant but it can and has be done.  As for supporting an odd number of
layers, the only odd number of layers I've ever seen used on a board design
is 3.

Hildo Guillardi Júnior (hildogjr) wrote:

Yes,@ Wayne I am doing this.
It is not elegant but works fine.
I think the DRC could warning the user "there a copper layer created
without any element". So in my workaround, I will know if is right and may
be useful in other situations (the design forgot something...).

jean-pierre charras (jp-charras) wrote:

For my info, what is the reason to ask for 3 layers instead 4 layers?
(AFAIK, the price to fabricate the board is the same)

If, for some reason, you do not want tracks and zones on a given layer,
just add a keepout zone for tracks and zones on this layer.

No need to change the DRC.

Hildo Guillardi Júnior (hildogjr) wrote:

My housing in Brazil use different price for 3 and for 4 layers.

The DRC doesn't need to change, but add a checking of empty copper layer to
warning the user that could be created empty Gerber files.

Jon Evans (craftyjon) wrote:

3 layer (and odd or unbalanced layer stacks in general) is also reasonably
common in flexible circuits.

mentioned in issue #3949 (closed)

Tacking on here...

The P-CAD importer can accept an odd number of layers and generate a KiCad board happily. However, the board then can't be opened because of this. See #3949 (closed) for more details of my specific situation.

!60 (merged) will add an Altium importer so it may be that a similar situation could become more likely (?).

I could think of a few different places where this could be handled, but I'll stick to just reporting the issue here since it seems related to this topic and Seth suggested it.

Hobbyist and some students start using Pcbnew with 1-layer single boards.

Not just hobbyists.

I design a lot of LED boards professionally (and I mean, a lot of them) and the vast majority are single layer designs (usually with aluminium subtract).

In the substrate design of BGA chips, odd-numbered layers are common

marked #8709 (closed) as a duplicate of this issue

marked this issue as related to #8709 (closed)

changed milestone to %7.0

removed milestone %7.0

marked #14709 (closed) as a duplicate of this issue

marked this issue as related to #14709 (closed)

marked #15380 (closed) as a duplicate of this issue

marked this issue as related to #15380 (closed)

Allow an odd layer number / asymmetric stackups (lp:#1829379)

Designs

Child items ...

Activity

Allow an odd layer number / asymmetric stackups (lp:#1829379)

Relates to

Activity