I used a NetTie to connect my Signal GND to GND. Similar to connecting AGND to DGND at one point. No problem, ERC & DRC were fine; on the Schematic Editor side, in the “Edit Symbol Fields,” I made sure to select the DNP check to prevent a generic block from showing in the “PCB Editor->3D Viewer”.
The problem is the NetTie solution did not propagate to the “IPC-D-356 Netlist file (FileName.d356).” When I imported this file into another GERBER viewer, a Netlist Error was reported between the two Signal GND and GND.
Is there something else I need to do to satisfy this IPC output file type? It doesn’t seem to handle the NetTie between the two GNDs.
What are your expectations?
The purpose of a net tie is to separate a net into two sections, even though they are a single piece of copper on the PCB. So it is only logical that an external tool gets confused and shows two different nets shorted when it analyzes the gerber files. A netlist is just a netlist. It has know knowledge that two copper nets are connected by the net tie.
A similar situation would be if you want to simulate a circuit that has net ties. For the simulator you could mimic them to be a 0 ohm resistor. (or estimate track resistance if the the simulator chokes on 0 ohm)
I thought that at least one function of the IPC-D-356 file was to do a physical probe check of the manufactured board against the net list. Probing a board that has connected copper elements that aren’t reflected in the net list sounds like it could be a problem to me.
I don’t know much about IPC-D-356, but I do know that the Gerber X2 standard has some extra features for flying probe tests. For example there is an ‘EtchedComponent’ keyword that can be used for items like PCB inductors, fuses, net ties etc. I just know of it’s existence. I do not know whether KiCad supports this or details of it’s use. If KiCad does not handle this attribute according to Gerber standards, then it is worth a feature request on gitlab.