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So I'm making a shield for a Raspberry Pi, and as you all Know the GND pins are internally connected inside the Raspberry. How can I tell that to Altium, so that It don't asks me to route them?

Altium thinks that pins 6 and 9 are not connected, but they are. (Internally)

enter image description here

Full PCB image: enter image description here

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  • \$\begingroup\$ Is the plane split in half, or is it actually connected through? \$\endgroup\$
    – ThreePhaseEel
    Feb 13, 2017 at 0:40
  • \$\begingroup\$ Just added a Photo of the upper part of the PCB. \$\endgroup\$
    – Sebastião
    Feb 13, 2017 at 0:45
  • \$\begingroup\$ Just Spot the problem. Near Pin 10 on the right side of the PCB the connection were broken. Thanks @The Photon for discovering it! \$\endgroup\$
    – Sebastião
    Feb 13, 2017 at 0:49
  • \$\begingroup\$ @Sebastião How wide is the clearance between the copper pour and traces? \$\endgroup\$
    – Nick Alexeev
    Feb 13, 2017 at 1:53
  • \$\begingroup\$ I have set 0,5mm \$\endgroup\$
    – Sebastião
    Feb 13, 2017 at 1:56

2 Answers 2

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You should not do that. You should connect both pins to ground on the board. This reduces the impedance between the ground node of the Pi and the ground of the circuit, reducing ground bounce and the risk of "unintended operation".

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    \$\begingroup\$ That makes sense. Can you explain me why Altium is saying that they are not connected? From what I can see they are connected through the ground plane. Full Image \$\endgroup\$
    – Sebastião
    Feb 13, 2017 at 0:40
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    \$\begingroup\$ It looks like connectivity might be broken near pin 10 of the SIP footprint along the right edge of the board. Try looking at it in single-layer mode or with the silkscreen layer turned off. \$\endgroup\$
    – The Photon
    Feb 13, 2017 at 0:43
  • \$\begingroup\$ You were right. Altium is to smart.... \$\endgroup\$
    – Sebastião
    Feb 13, 2017 at 0:47
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    \$\begingroup\$ +1 That's still a fairly thin and distant connection- you might want to stitch the pieces of ground plane together with fat traces on the opposite side. It costs nothing and will improve the ground integrity. \$\endgroup\$
    – Spehro Pefhany
    Feb 13, 2017 at 3:18
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I think the easiest way is to delete the net from the pins in the schematic (make the pins unconnected to any net in the schematic). Then it would not reference them in the layout view.

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  • \$\begingroup\$ That was the only way I know. But for sure there an other way to do it... \$\endgroup\$
    – Sebastião
    Feb 13, 2017 at 0:14
  • \$\begingroup\$ @Sebastiao I'm not so sure. But let's wait for other answers [or lack thereof] and see. \$\endgroup\$
    – Nick Alexeev
    Feb 13, 2017 at 0:22

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