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Copper over footprint pins

Olek
I use Allegro/OrCAD PCB Editor for pcb design.

I have problems with irregularly shaped pins.

“Shapes” not always can be used to define padstack for such pins.

In such cases I have to add copper over the pins.

Example:

Vishay POWERPAK-1212-8 footprint requires exposed copper that overlaps partially two pins.

I would like to show 8 pins on the schematic part, so the footprint must have the same 8 pins.

I have added copper (etch) partially overlapping these pins.

I got DRC errors.

After I placed symbol on the board the DRC errors remained.
The question is: How to get rid of these errors?Can I do something with the copper to get rid of errors, or maybe I can turn off DRCs for the specific pins (or copper) on board level. Another example when I can't use "Shapes": Padstack pad that are “C” shaped with the pin origin located outside the shape (beyond the copper).

I think that routing to such pin will be impossible.
  • redwire

     You've got several "mixed" solutions here... all will probably work.

    But to answer the question you directed at me -- a shape/pin violation will go away when netlisted.  You need to be aware of shape-shape clearance rules that have to be met.

    Or -- add the shape/paste to the board after you've placed the part -- your choice.

  • redwire

     Here is a zip file with a part I made up with two copper shapes... one shorts across pins 7&8 and the other across 5&6

    In the board file with _no_nl (no netlist) you see there are DRC errors with the pins touching the shape.

    In the other board I attached a netlist to short the pins and the DRC errors go away.

    Hope that helps.

    shorted_pins_demo.zip
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