Two Copper Pour Problems

Making PCB Layouts, Manual routing, Auto-routing, Copper pouring, Updating from Schematic, Manufacturing Output
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skrasms
Posts: 8
Joined: 25 Feb 2012, 22:18

Two Copper Pour Problems

#1 Post by skrasms » 14 Jan 2013, 00:45

These issues both show up in the attached file. It is a simple test case.

First, I can’t get a copper pour to fully surround vias when there are multiple vias close together. This appears to be an issue with the copper pouring algorithm. In the left-side BGA of the attached PCB, note that the ground copper does not close the gap between the two non-ground vias. As shown under the BGA on the right, I have enough space to run an 8 mil thick ground trace between the two vias and not flag any DRC errors. How do I make the copper pour fill that area?

Second, why do copper pours fail DRC when they are set to a clearance that matches DRC settings? Shouldn’t that be a guaranteed pass? I always have to make the pour clearance greater than the DRC settings or else I get errors. For example, in the attached PCB I have the pour clearance set to 7 mils while the DRC spacings are all 6 mils. That passes. However, if I change the pour clearance to 6 mils, matching the DRC settings, I get errors.
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RDC
Posts: 18
Joined: 26 Mar 2011, 20:17

Re: Two Copper Pour Problems

#2 Post by RDC » 14 Jan 2013, 01:40

First - In the Copper Pour Properties, change your Line Width from 0.025in to 0.004in

Second - Good question.

phangmoh
Posts: 22
Joined: 27 Jul 2010, 10:38

Re: Two Copper Pour Problems

#3 Post by phangmoh » 14 Jan 2013, 04:27

RDC wrote:First - In the Copper Pour Properties, change your Line Width from 0.025in to 0.004in
Some manufacturer will charge your higher price for using thinner line width. I think 8-10 mil is pretty standard. 25 mil is huge!

RDC
Posts: 18
Joined: 26 Mar 2011, 20:17

Re: Two Copper Pour Problems

#4 Post by RDC » 14 Jan 2013, 05:34

8-10mil doesn't surround the Via on his design, that's what he wanted to know, only a 4mil setting does.

skrasms
Posts: 8
Joined: 25 Feb 2012, 22:18

Re: Two Copper Pour Problems

#5 Post by skrasms » 14 Jan 2013, 21:58

Thank you for that solution. That is confusing about the fill characteristics since I am not using a hatch pattern. It seems like only the clearance should matter. What do line width and spacing settings mean for a solid plane?

Setting line width and spacing to zero (which the software then changed to 0.004" - why?) works fine.

Strangely, that change to line width and spacing also has the design passing DRC when the plane clearance matches the DRC spacings.

Alex
Technical Support
Posts: 3261
Joined: 14 Jun 2010, 06:43

Re: Two Copper Pour Problems

#6 Post by Alex » 16 Jan 2013, 09:56

Copper pours consist of many lines. User can enter line width and line spacing. Smaller parameters increase coper pour accuracy but slow down the software while updating, DRC, etc and increase file size.

Minimum line width is 0.004", if you enter zero settings software corrects this.

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