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Connecting symbol shapes to internal layer

TH Designs

On the connector shown below I want to connect the shapes around the perimeter to the internal gnd layer. I have selected each shape and assigned the net "gnd" to each but I get no ratsnest showing a connection needs to be made. The status command does not show them as unconnected either.

Previously I would have edited the copper area to assign the net, then placed a "free via" to connect to the gnd plane. I don't see a method to get a small hole into the shape.

I tried to add pins to the library part, but that requires adding additional pins to the schematic symbol. Plus, can you even have a pin inside a shape?

Tom

(I sure picked the right avatar........)

  • fxffxf

    Ratsnest are not displayed to shapes. There is an Isolated shape report that you can acccess via the Reports or Status dialog. If the shape is isolated then you will need to tie it to the appropriate net by via routing from the shape to an object on that net. If could just mean that you need to add a via from  shape to another layer to tie it to a already connected shape. This can be done via the add connect command.

    This assumes you are using positive planes.

  • TH Designs

    Maybe this is how it is done, maybe I just stumbled onto something.......

    After I assign the 10 shapes around the connector to the "GND" net, I was expecting to see a ratsnest that I could clikc on and route from. Didn't have one. Since I have spent close to three hour on this, my frustration level is climbing so I just tried Route - Connect, clicked on the shape and made a short trace, double clicked to insert a via and the connection was made to the GND plane!

    I tried the same thing on a shape that did not have any net associated with it. It allowed me to route a trace and place a via, but no connection was made to either plane (which I would expect).

    So it looks like assigning the shape to a net and the MANUALLY putting in a trace from the shape to a via will connect it to the gnd plane. (I would really like the via in the shape, I'll try that also)

    I don't know if this will remain when a new netlist is loaded, but I'm hoping it stays.

    Tom

  • TH Designs
    fxffxf said:

    Ratsnest are not displayed to shapes. There is an Isolated shape report that you can acccess via the Reports or Status dialog. If the shape is isolated then you will need to tie it to the appropriate net by via routing from the shape to an object on that net. If could just mean that you need to add a via from  shape to another layer to tie it to a already connected shape. This can be done via the add connect command.

    This assumes you are using positive planes.

    Looks like we were typing at the same time................ You stated what I think I figured out.  Thanks!

  • TH Designs
    fxffxf said:

    Ratsnest are not displayed to shapes. There is an Isolated shape report that you can acccess via the Reports or Status dialog. If the shape is isolated then you will need to tie it to the appropriate net by via routing from the shape to an object on that net. If could just mean that you need to add a via from  shape to another layer to tie it to a already connected shape. This can be done via the add connect command.

    This assumes you are using positive planes.

    Looks like we were typing at the same time................ You stated what I think I figured out.  Thanks!

  • ScottCad

    Tom on those connectors that have mounts, you might want to think about making the pads as an actual padstack, i.e adding a pin for each one. On the schematic side you can either hide those pins or re-draw the symbol to include them.

    My preference is one from electrical/drc checking. Thing is the symbol might not look ideal on the schematic but doing those mounting pads as pins has the added advantage that your schematic will exactly match that board, plus you will also get a net.

    I think having floating pads in a footprint can lead to errors on the board, sometimes costly ones.

    Anyway just a suggestion.

    Thanks Scott

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