How does one remove non-functional pads in vias?

Question

How does one remove non-functional pads in vias? I’m not finding the requisite check box(es) or other settings.

I need to minimize the discontinuities in at least the higher frequency paths, want to somewhat shrink the resulting anti-pads on the ground and supply layers to improve current return impedance, and it can often contribute to better routing in the vicinity of vias.

I was hoping to even set it by layer and perhaps set the restring by layer, having it depend upon whether there is a trace connected or not.

The only alternative seems labor-crazy intensive, effectively:

Setting normal via restring values and applying the appropriate teardrops to the various layers
Minimize the restring values to the smallest NFP values wanted for the board, and
apply a circle to each and every capture pad where there is a trace to be connected
subsequently approving the circle overlap DRC errors

Please describe a better way…?

autodeskguest · Answer

On 12/04/2015 2:33 a.m., Bruce Mellen wrote: How does one remove non-functional pads in vias? I’m not finding the requisite check box(es) or other settings. I need to minimize the discontinuities in at least the higher frequency paths, want to somewhat shrink the resulting anti-pads on the ground and supply layers to improve current return impedance, and it can often contribute to better routing in the vicinity of vias. I was hoping to even set it by layer and perhaps set the restring by layer, having it depend upon whether there is a trace connected or not. The only alternative seems labor-crazy intensive, effectively: Setting normal via restring values and applying the appropriate teardrops to the various layers Minimize the restring values to the smallest NFP values wanted for the board, and apply a circle to each and every capture pad where there is a trace to be connected subsequently approving the circle overlap DRC errors Please describe a better way…? -- To view any images and attachments in this post, visit: http://www.element14.com/community/message/146824 So you mean " How does one remove the unused restrings from the inner layers" This is all about 'pad stacks' and the ability to specify the restring by layer or even pad/via. Historically this feature was requested many times and has not been delivered by Cadsoft. Jorge did mention recently that they were working on keep-outs for the inner layers so perhaps that implies pad stacks are coming. As an aside; I note that many of the power users who were vocal about their need for pad stacks either are known to have moved away from eagle or are not heard from very often these days suggesting they have voted with their feet. You may care to investigate the following ideas: (1) Edit/delete these unwanted restrings in your Gerber editor. (2) Don't place the circle, that you subsequently have to approve in the DRC, on the signal layer but rather on a user defined non signal layers and merge the signal and non signal layer when you generate the Gerber for that copper/signal layer. (3) Create a ULP to automate the 'labor-crazy' part. Again, start as you have with minimised inner restrings. Use the ULP to locate the inner restrings that have traces connected. The ULP then adds a polygon (circle) over that restring of the required size. The polygon is given the same signal name as the trace so there are no DRC errors. HTH Warren

autodeskguest · Answer

On 11.04.2015 16:33, Bruce Mellen wrote:> How does one remove

non-functional pads in vias? I’m not finding the

> requisite check box(es) or other settings.

This subject is non trivial. Some manufacturers need these rings to

prevent de-lamination of the stack and/or to make a proper via at all.

The ones that don't need it may or may not remove them wihtout asking.

The moral is to always specify what you want with them, wether or not

they are in your gerbers. The specification of the pcb manufacturing is

a process to be taken seriously, especially when you are talking about

high speed signals. Don't go easy on it.

On the other hand, if Eagle supported a way to remove them, it would

direct tell the manufacturer that you don't want them, and allow the

manufacturers DRC to notify if their process doesn't allow.

How does one remove non-functional pads in vias?

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