Add custom DRC rule to exclude checking track inside polygon

[mameco3798]

Hello All,
I am getting a lot of these violations (many of which are intentional). How do I exclude these DRC violations. The footprint has a F.Cu polygon on top of a square pad (footprint downloaded from manufacturer).

  Application: KiCad PCB Editor

Version: 6.0.6-3a73a75311~116~ubuntu20.04.1, release build

Libraries:
	wxWidgets 3.0.4
	libcurl/7.68.0 OpenSSL/1.1.1f zlib/1.2.11 brotli/1.0.7 libidn2/2.2.0 libpsl/0.21.0 (+libidn2/2.2.0) libssh/0.9.3/openssl/zlib nghttp2/1.40.0 librtmp/2.3

Platform: Linux 5.4.0-121-generic x86_64, 64 bit, Little endian, wxGTK, xubuntu, x11

Build Info:
	Date: Jun 20 2022 15:49:56
	wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
	Boost: 1.71.0
	OCC: 7.5.2
	Curl: 7.83.1
	ngspice: 36
	Compiler: GCC 9.4.0 with C++ ABI 1013

Build settings:
	KICAD_USE_OCC=ON
	KICAD_SPICE=ON

Many thanks.

Edit 1: MAX77757JEFG435 is the part. I downloaded the footprint from their website.
https://vendor.ultralibrarian.com/Maxim/Embedded?vdrPN=MAX77757HEFG360%2B

[Jonathan_Haas]

Polygons on a copper layer aren’t the correct approach in KiCad, they can’t have a net so they should only be used for decoration or not at all.

If part of a footprint, convert these to custom pad shapes. If part of the PCB, convert them to copper fills. That would be the proper way instead of ignoring the DRC errors.

[mameco3798]

Thanks Jonathan.
I discarded the model downloaded from the manufacturer (which has polygons in the footprints) and started from scratch using kicad’s “Custom (rectangular base)” and “Custom Shape Primitives”.
The issue is that two pins are supposed to overlap. So I duplicated the pins and laid them on top of each other.
However that approach doesn’t work either.

Thanks.

[Jonathan_Haas]

You don’t need to create custom shape primitives, that’s obsolete functionality. You can simply right click a pad and go onto pad editing mode and draw whatever you want.

Overlapping pads should probably be a single pad. I think kicad will automatically merge them if needed.

(Not sure about exact terminology, if you need help I can send screenshots)

[mameco3798]

Ah. Just saw that option. Got that irregular pad shape sorted.
I was going about it the hard way.

I would appreciate your help (screen shots) on overlapping pads.
I still can’t start a trace with two overlapping pads.
Even though the schematic shows them as being connected to the same net.

[Jonathan_Haas]

@mameco3798

I would appreciate your help (screen shots) on overlapping pads.

There should be no problem with it.

Two pads placed normally:

Connect them using a rectangle (press ctrl+e with pad selected, add rectangle or other shapes, press ctrl+e again):

(obviously very simple, use better shapes if you want)

Place them on PCB and draw tracks:

If this doesn’t work please post example board or at least make good screenshots. Make sure there are no polygons left. You might want to give pads that are connected the same pad number if that’s not already the case.