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Assigning net to copied Via+Cline? Alternate method for custom fanout?

Gipper

I'm in the process of laying out a series of DDR4 devices consisting of two ranks of five devices each. There will be a lot of repeated routing, even within the same device. Being as I want to match the trace lengths, I also want to match the tuned fanout at several pins. Some of the fanout is shown in the image below. The tuning is there to match other lengths within the DDR4's address bus.

I want to copy these Cline and vias to other pins within the routing of this device. 

Currently, if I copy the Via+Cline and move it to the pin I want it to connect to, it automatically assigns the Via+Cline to "GND". I assume this is because my ground plane is directly under this layer. Then, if I re-assign the net of the via to match the desired pin, the Cline goes to "No Net" and cannot be changed or modified - at least I don't see an option to assign a net to the dummy trace. I struggle to manually route a perfectly matched trace, so I am hoping to copy these traces.

After I complete the routing for the first device, I would like to copy the Clines and vias to the next device as this is a fly-by topology.

Is there a method for copying a Cline+Via, then re-assigning the net on the pasted Cline+Via? 

My tool set is OrCad PCB Designer Pro 17.4 S007.

  • steve

    The best way to do this is to use a Via Structure. Look under the Route - Structures - Create

  • Gipper
    in reply to steve

    I will try that out. Thank you!

    On a slightly related note, I also need to copy the Clines to the bottom layer with the same net. The idea of Z-Copy sounds like it would work, but it does not appear to work for Clines. Is there an appropriate tool to perform this function?

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