PCBnew DRC error

Thread Starter


Joined Jun 30, 2019

I am so glad I got autorouting to route this. My hair would have been so long before I would have finished.

So, I ran RDC and got this error:


Joined Jan 18, 2008
Those errors describe things that were not routed, like pad 8 on U4:

The images are too small for me to see the other error. In many programs, if you click on the error, it will be highlighted.

Often, one can manually route just the error or rip-up a few other routes and do them manually.


Joined Apr 11, 2010
Your ground plane has isolated islands. Thus the connection from U4:7 to U4:8 doesn’t. Look at the ground plane pour and make sure there are to isolated islands. If you find any (and I’m betting you will), you’ll need to jumper them together. Either with jumpers, or vias to a track on another layer and back again. I’d add several jumpers for each isolated section of the ground pour.


Joined Jan 18, 2008
You can put the ground plane on top and bottom. Be sure to "knit" them together with vias. I sometimes also use a power plane (different priority), but that depends on the circuit. For the example I showed above, I have ground top and bottom. Power is just a somewhat wider "rail" trace.


Joined Jan 18, 2008
Knitting top and bottom together will not show up on DRC. Only one via may be necessary to avoid an error. You will see lots of examples in datasheets.

For example, the small new chips will often have their ground planes knitted to a much large area of copper on the bottom. That is for heat transfer. As for electrical, it's not entirely the more the better, but do be generous.