I am using PCB123 to do a PCB layout and I have a part with some oddly shaped pads specified in the part's recommended footprint. It seems that in the footprint editor, there are only 3 options for pin shapes. Therefore, I chose the closest one (square pad) and then extended them to match the recommended footprint using filled polygons in the metal layer.

The footprint in question belongs to the Luminus Devices XNOVA 3020 led, datasheet here

Package & Footprint Drawing

My problem is that I get DRC errors indicating that the polygons are too close to the pins. I cannot find a way to tell the footprint editor that the polygons share the same net as the pins. Normally on the general layout, I can specify to which net the polygon belongs, however in footprint editor, this menu is grayed-out.

Does anyone know how to solve this problem?

  • \$\begingroup\$ have the polygons got a Net assigned to them properly? Perhaps on the PCB itself can you detach/unlock/explode the primitive objects and manually assign the nets if you cannot do it in the footprint editor? I can see how the footprint editor will not let you select nets, it doesn't know what nets will be in all your future projects ;) haha \$\endgroup\$ – KyranF Oct 17 '14 at 5:53
  • \$\begingroup\$ As a really ugly workaround you could assign each of the polygons a pin number and tie them together in the schematic. Hopefully there is a better way. \$\endgroup\$ – Spehro Pefhany Oct 17 '14 at 6:04
  • \$\begingroup\$ Is there a problem with just making the pins huge and cover those areas without the little notches/gaps? \$\endgroup\$ – KyranF Oct 17 '14 at 7:48
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    \$\begingroup\$ @KyranF I don't really understand the recommended footprint that the manufacturer has provided. Personally, I don't see a problem with making the pads larger, rectangular, and fully inclusive of the specified pads. The other thing I find odd about the footprint is the specificity of the dimensions; One dimention is specified to .005mm even though the tolerance specified is only .05mm. \$\endgroup\$ – kjgregory Oct 17 '14 at 16:55
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    \$\begingroup\$ @KGregory yes, it is strange. If it was me, I would just make two nice big fat pads for thermal and physical reasons, and the fact it's annoying to make them like that \$\endgroup\$ – KyranF Oct 17 '14 at 19:28

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