Adjacent zones with different properties

[0rotas0]

I am trying to make a layout with a single ground plane but with one half using thermal relief connections to pads and the other solid (to sit underneath a heatsink). I have two zones with the right properties but the trouble is when they touch they merge into one. I am working around the issue by leaving a small gap and running several tracks between them but is there a better way to do this?

[Rene_Poschl]

You can overwrite the zone properties on the footprint or even pad level. So give your heatsink footprint the zone connection property “Solid” while keeping “Thermals” for the zone.

[0rotas0]

Ah I knew I had to be missing something. Thank you very much.

[SembazuruCDE]

You may also be able to make sure the zone with the solid connections override the larger one that uses thermal reliefs where they overlap. Play with the relative priorities of the two zones and watch your zone connections with the filled area showing. But, because the two zones are the same net, they will flood together.

I just did a quick demonstration:

Here is a screen shot of the filled areas with “Do not show filled areas” selected in the left tool bar:

You can see there is a filled zone around Q1 on the F.Cu layer (red) that is withing a larger filled zone that I have drawn outside my board edges.

Here is the settings window for this smaller filled zone:

The two fields to take note are I have the Default pad connection set to “Solid” and the Zone priority level is set to “1”. (In my main zone these two fields are set as “Thermal relief” and “0”, respectively.)

Here is what that section of the board looks like with “Show filled areas in zones” selected in the left tool bar:

You can see that the GND pad of Q1 now has a solid connection to the ground plane, but otherwise there is no fill differentiation between the ground planes.

If this is what you are looking for, it might be a simpler task of adjusting the zone settings vs. going in and hand editing all the pads, through holes, and vias that you want a solid connection to the ground plane.

Hope this helps.