Nettie connections in internal layer - or workaround

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I couldn’t find an answer to this but hopefully someone can give me a better workaround. I have a 4 layer PCB with a 2 post TH PCB terminal on the top layer. Pin 1 is -Ve (return to power supply). On the top layer I connect a ground trace to the pin - NET PWRGRND. On layer 2, I have a Ground plane which I want to connect at this pin. On layer 3 I have another Ground plane which I want to connect to this pin. The planes should NOT be connected to each other at any other location.

Currently, I created a 3-pin NETTIE in the schematic and edited the footprint so that it had one SMD pad and two TH pads. I then connected the grounds to a seperate pin of the NETTIE. In the PCB this works: the SMD pad connects to the top trace, the other two pads route down the board and connect at each layer. I can edit the pads to give a solid connection (i.e. no thermal relief) which works for the TH but not the SMD pad for some reason - the copper fill just flows around it, attaching at one edge. Take a look at the image to see what I’ve currently got. Red is top layer, Yellow is layer 2, Pink is layer 3. The image was taken with layer 3 active; layer 2 pad is connected in exactly the same way to the yellow copper fill.

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It’ll work, but what I really want to be able to do is just tie the grounds to the pin at each layer - almost like I want a NETTIE on the internal layers. I don’t really want this NETTIE ‘spur’ on the top layer. I can reposition it, in that general area, and I suppose I could edit the footprint to make the connecting trace shorter.

Is there a better approach?
If not, is there a way to make pad 3 a solid connection to the copper fill?

Thanks,

Andrew

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Select the SMD pad and hit E for edit.

Second tab ‘local clearance and settings’ under ‘connection to copper zones’ set ‘pad connection’ to solid.

That should fix it.

Cheers

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Thanks Jos, but I already have done that - it’s how I got the other pads to fully connect. I think it’s because there is a track between the pads. As the Nettie is on the top layer, fills there route around because they see the track, but on internal layers there is just the through hole pad so it connects up solidly.

What I’m really looking for is a better way of doing it. I feel like joining multiple nets at one point is a fairly common requirement with laying out PCBs (star grounding, star power) so I was hoping someone has a good solution. Something like defining a pin/pad as belonging to multiple nets.

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Multiple nets is exactly what those net-ties are meant to tie. Sounds like you need to whip up your own very specific footprints.

Then again the current implementation of net ties is only temporary. The next major release will address this so the story goes.

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Something like that will (probably) be possible in 6.0, but not yet.

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Thanks guys. Looks like I’ll have to play around with foot prints then. May work better with the Nettie on the bottom layer with all TH pads.

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