Same polygon connected to multiple nets?

I have a pcb antenna design with a polygon that needs connections to two different nets. That creates a short at DC, but it’s what’s required for the 2.4 Ghz antenna.

How do I handle that? Do I add two pads on the same polygon with different pin numbers?

Yes, and then you must put the magic phrase “net tie” in the keywords field so DRC knows it’s ok for the footprint to short the nets.

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Thanks, but it’s been a few years since I used KiCad. Where do I find “keywords”. Footprint editor?

I see several video tutorials after searching on Kicad net tie. Bed time now, but I’ll check it out tomorrow.

Thanks for the tip!

Properties dialog in the footprint editor

Like this?

I assume the quotes were required (“net tie”) because of the space between net and tie.

Still DRC is complaining

The footprint includes the antenna and minimum ground plane polygons.

There’s a via that connects top and bottom polygons (gnd). I used a through-hole pad (2 in pic above) for that.

I used an smd pad for the feed point (1 in the pic above).

So, those two nets are shorted together in the footprint. Is “net tie” keyword the way to handle this?

Kicad 6.0.8

I checked out some antenna footprints in the Kicad RF_antenna library. None of them have “net tie” in the keywords field.

Maybe I just have to live with the DRC errors?

Have you tried adding them to the schematic?

No, quotes not required

I checked out some antenna footprints in the Kicad RF_antenna library. None of them have “net tie” in the keywords field.

Not sure why, either there’s another secret keyword I don’t know about or they predate DRC checking copper polygons and do indeed cause errors in modern KiCad. Probably the latter.

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Leaving off the quotes fixed the issue.

Thank you!

For what it’s worth, the “net tie” hack goes away in 7.0, replaced by a facility that states which pads combinations are allowed to short nets.

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“net tie” in footprints works, but it turns out that traces in footprints don’t get included in a HyperLynx export (which I need for import into openEMS).

So, I need something similar in pcbNew. I need to connect two nets to the same zone.

I really DO want to connect an zone on net ANT to the GND zone

I tried adding the net tie to the schematic, but it did not help:

image