'Line to Same net spacing' error and disconnects

In Allegro there are multiple DRC modes that can be enabled / Disabled.

Suggest you disable "Same Net Spacing" as it is only useful if the physical nets are actually the same type.

Go to Setup > Constraints > modes to access it.

Try that out and see how it works for you.

Thank you Excellon1,

However there is an issue, the design is with a multi-national company AND the checkers replace the rules with a corporate set which would have the 'Same Net Rules' turned on and they would refuse the checking process! This is not a viable option.

The nets appear disconnected and this is a problem with the design/software and not a DRC issue. The software broke the connections to the pads and then failed to remove the trace, but both the trace and pad are the same net???

Thank you Excellon1,

However there is an issue, the design is with a multi-national company AND the checkers replace the rules with a corporate set which would have the 'Same Net Rules' turned on and they would refuse the checking process! This is not a viable option.

The nets appear disconnected and this is a problem with the design/software and not a DRC issue. The software broke the connections to the pads and then failed to remove the trace, but both the trace and pad are the same net???

  I feel your pain, I am always fighting others in my design, suggestion that might help.  Once you get you constraints set, export them to a dcf in a personal saved space, and you can reread them back into Allegro anytime you need to?  Sorry, not a fix, but an work around..  ?? maybe

Did you change the design units or accuracy at any stage? If so this may have caused the disconnects if you didn't allow enough decimal places when changing units. If you do this you actually change the design.

This sounds like some sort of ECO was performed on the board and after the ECO process etch remained on the board which would happen if etch removal was not checked prior to generating a new netlist.

I assume you are using Orcad Capture as the front end on your design.

Maybe try this. If etch exists on the board but there is no net associated with that etch etc then go ahead and delete the offending etch. Next either re-generate the netlist or use the existing one. In the PCB editor you can use import logic to pull in the new netlist and update the board. There is an option when either generating the netlist in capture to allow etch removal. This same option exists if just pulling in the netlist via "Import Logic"

Before you do this. Save your existing board as a new name. Apply the netlist to the new board name. If all goes good then you can do a save as and use the real board design name.

To me right now based on what you indicate there is a problem with the actual board, schematic sync so I think that would be a good place to start to try resolve the issue. The last thing you want on any board is dead etch that is not part of any net.

Let us know how the above works out for you.

All the best.

Hello Steve,

There were two different Grounds AGND and DGND which were shorted on the later design and the Global Short was used  to allow these to be joined.

The pads are now all called AGND (Some were DGND) and the traces (which were DGND) are also called AGND. The design was made in Design Entry Allegro and not Capture. The design was routed before the grounds were joined and an ECO was run and the result is the trace changed to AGND and the Pads were changed to AGND but the connection was broken and not reconnected.