Eagle and Vias

[drog_trog]

in Eagle, do you need to have different via pad sizes for different trace widths?

[culturejam]

I believe the pad size for vias is set in the design rules. And you can always select the via and adjust the drill diameter on a layout. There's got to be a way to set it globally, but I've not figure it out (nor have I tried).

[madbean]

You via diameters should be at least as large as your trace width. I set all my vias to a drill size of 27.x mil and that covers the two trace widths I use: 10 mil audio and 24 mil power.

[drog_trog]

Ok, what would happen if your vias were too small

[gtr2]

I believe the pad size for vias is set in the design rules. And you can always select the via and adjust the drill diameter on a layout. There's got to be a way to set it globally, but I've not figure it out (nor have I tried).

You update the eagle.scr

Mine is heavily modified now over the years.  I have custom menus and scripts for my entire workflow.  Sadly, all the workaround time spent I could have just migrated to Altium.  Especially doing 3D mocks.  I know the new version is more streamlined but I paid for 7 and am not moving into the contant update subscription model.

Anyhow, add this to your eagle.scr anywhere in the BRD portion of the script (change to whatever size via you want, use in instead of mm if using Imperial)

Set drill 0.4mm; #Make vias 0.4mm;
Set diameter 0.7mm; #Make diameter 0.7mm
Change Shape Round; #Make vias round

Josh

[culturejam]

You update the eagle.scr

Ah! See, I knew there was a way.

Thanks, Josh. That's a real pro-tip.

[gtr2]

Here is another via thing for 4+ layer PCBs

You'll need to set up the DRC for the inner layers for the vias.

You'll need to uncheck the box to eliminate the non-functional pads (NFP) if you have any diameter set other than "auto".

There is much debate about NFP, but for analog, they are fine to leave if you don't want to mess with the DRC.