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I am using an older version of Altium (14.1) and I cannot stop the short-circuit errors from being flagged.

I am trying to route an eMMC BGA that has many pads that are NC (internally not electrically connected) and I need to trace over some of them to escape the signal. When I try to use interactive routing, unless I use the Ignore Obstacles mode, I cannot trace over them. That is not the main issue however.

My main issue is how do I get the rules check to ignore the short-circuit errors and/or the clearance violations that I am getting? I do not know which rule to set nor how to setup the query to properly handle this issue.

Any help would be greatly appreciated.

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Running traces over NC pins is still very poor practice, and I do not recommend doing this. It would be VERY unprofessional. I suggest finding a way to avoid the pads, even if it means adding another layer to your board and putting in some vias. That would be the correct way to do it.

That being said, if you absolutely MUST trace over pads, you will need to add the NC pins to the schematic symbol and in the schematic assign them the same net as the track that you intend to lay over them. They will appear in the PCB design as a required connection point, so select your nets and place the tracks wisely.

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  • \$\begingroup\$ Thank you for the suggestion. I realize that it is not the best practice to trace over other pads but if the space between the pads are too small to put vias between them, this is really the only option. That being said, I discovered that I can individually change the nets of the individual pads of the component itself on the PrjPCB without having the connections on the schematic. But, this will not help track the original pad. Is there a way to do the same thing but by setting up the rules proper? \$\endgroup\$ – Experiment-626 Feb 8 '18 at 20:35
  • \$\begingroup\$ You can change the nets of the pads themselves in the PCB editor, yes, but then you will get errors indicating the PCB does not match the schematic. In my answer I told you how to make it work without throwing errors. \$\endgroup\$ – DerStrom8 Feb 8 '18 at 20:45
  • \$\begingroup\$ If all else fails, I will definitely change the schematic symbol to connect the pins I need to overlap to the net it uses because I do not really like to see any errors. However, is there a way to set a rule to do the same thing? I have made some pretty creative rules but I cannot seem to find the correct language to get this design rule issue to comply. \$\endgroup\$ – Experiment-626 Feb 8 '18 at 20:58
  • \$\begingroup\$ You would have to get impractically specific with the query. Just change the schematic. \$\endgroup\$ – DerStrom8 Feb 9 '18 at 1:24
  • \$\begingroup\$ I do not mind getting impractically specific with the query. As I said, I have done things like that before. I just do not know what to put in the query nor which rules I would need to query to get it to work. Does anyone have any idea as to what to put in the query to make this work via design rules? \$\endgroup\$ – Experiment-626 Feb 9 '18 at 13:52

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