Noob question about trace to pad connection


#1

Hi,

First time I’ve used KiCad, so I’m curious if there is a step I’m missing. I’m trying to terminate a relatively wide trace at a thinner pad. The trace over-runs the pad if i connect them, and comes up with a not connected error if i stop it short. Hopefully the picture illustrates my problem (highlighted in yellow). Any easy way to resolve this?

many thanks


#2

They do look like rather narrow pads, but if you are sure they are correct then one way to resolve the issue is to stop the trace short so that it does not overrun the pad and then, to satisfy DRC, use a much narrower trace to connect the center of your trace to the center of the pad.


#3

The pads are technically correct, though i suppose i could also widen them a little. I’ve printed these once before, and just lived with the slight over-run.


#4

If the discrepancy between the wide trace and the narrow pad is so great that the short length of “much narrower trace” creates an undesirable bottle-neck effect, you could define a small fill-zone to make the transition. Even that is more work than I’d like to do for more than a few instances of this footprint.

If you widen them, adjust the center location so the additional width falls outside the component body. That will preserve the gap between pads - i.e., pad 1 to pad 3, and pad2 to pad3, in your picture. (This is often done to create a layout that is friendly toward hand-soldering.)

If you modify the footprint, consider adding short stubs to pads 1 and 2. Make the stubs wide enough to smoothly terminate the wide traces. There are several posts on the Forum talking about how you can create pads that are more complex than simple circles or rectangles, by defining multiple overlapping pads.

Dale


#5

Hi Dale,

This is exactly what i ended up doing. Problem solved, love this program so far.