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Donut Pad to Ground Connection

rmerrill

I am using the Pad Editor in Ver. 17.2-2016 S011 at the moment.

I am trying to create a Pad Stack for a Non-Plated Mounting Hole that has a Donut Pad on the Outer Layers to connect to Ground.

Chassis Ground are on Internal Layers so, within the Board, I will be placing a Via and then adding a Trace to the Copper Donut Pad.

Once I define the Outer Layers as a Donut, the Usage Options at the bottom the Summary Page adds "Enable connect by touch: No"

As I seem to need to use Touch, to connect it to a via, without a DRC violation, I am expecting that this should say "Yes".

Richard

  • In order to make the mounting hole able to connect to a net you will need to create a part (.dra) and add the pad as a pin. You can then create a part in capture and make the necessary connections.
  • I did make a "Mechanical" Part and added the Pad Stack as a pin.
    I then placed the Part manually onto the board.
    Then I tried to connect a via to it. Visually it looks fine, but the DRC Marks it as an error.

    I did try and add it, as you mention, as an "Electrical" part, and, added within Capture with a connection to Ground, but, by doing it that way, the Inner Layer Planes would connect also.
    As it is a non-plated hole, even without inner layer pads, it would create thermal ties to the hole.
  • In the Symbol Editor, Edit>Properties, Pins On in Find, pick the Pin with a left-click, locate the Dyn_Thermal_Conn_Type entry in Edit Property and select it, use Assign, and set None for the Type for Cdn_Inner_Plane and Cdn_Inner_Signal, for example to prevent connection. (You can set other layers and options for the Thermal Connection Type)
  • Yes, thank you, that will work for me until a Hotfix comes through to perform the operation as documented.

  • One thought is to define the Donut Pad padstack as Plated and enable smaller multiple drills that land inside of the donut pad boundary which would connect to the internal plane layers.  All you would need is to place a separate non-plated drill padstack in the middle of the Donut Pad padstack.  It could be done all in the same package symbol with the Donut Pad connection driven by the netlist.

    Hope this help,

    Mike Catrambone


     


     


     

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