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Electronics => PCB/EDA/CAD => KiCad => Topic started by: paulca on February 17, 2018, 10:08:24 am

Title: DRC Unconnected Issue
Post by: paulca on February 17, 2018, 10:08:24 am

Can anyone explain why KiCad thinks this pad is unconnected?

You can see the rat nest line going down to the IC +5V net.  However it is securely connected to the +5V net on the LEDs adjacent to it.  It is in a row of 6 LEDs and the others all seem fine.  I have remade both the connection on the LED and on the IC but the error will no clear.

Also, I assume connecting an SMD IC's ground to the back plain with an orphaned Via is acceptable?

(http://i.imgur.com/E2TD0V4.png) (https://imgur.com/E2TD0V4)

Title: Re: DRC Unconnected Issue
Post by: awallin on February 17, 2018, 10:58:53 am

I've seen similar things, the DRC just thinks your net is broken somewhere along the line. Redrawing it piece by piece is a 'stupid' solution but seems to work. Particularly if you redraw/edit things a lot, or re-name on the SCH-side and import a new netlist to PCB this tends to happen...

sorry not much of a solution here.. just a feature not a bug ;)

Title: Re: DRC Unconnected Issue
Post by: paulca on February 17, 2018, 11:05:42 am

Yea, I figured it was just a bug/feature.  Assuming the manu leaves copper there it will be connected.

Title: Re: DRC Unconnected Issue
Post by: donotdespisethesnake on February 17, 2018, 11:09:14 am

Beware that the air-wire is not necessarily where the problem is - KiCad draws the shortest line connecting isolated nets, the problem could be somewhere else.

Also worth noting is that the "new" canvas has different code to the legacy canvas, and there have been some bugs with the connection algorithms.

Title: Re: DRC Unconnected Issue
Post by: paulca on February 17, 2018, 11:11:51 am

Ah... yes...   :-[ :-[ :-[

I found a whole section of +5V net unconnected, half the board!  "Highlight Net" comes in handy for that :)