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In PCBnew, there is a ratsnest that I cannot comprehend why its there. This is it:

enter image description here

As you can see, there is supposedly connection between pins 3 and 4. However, if you look at the schematic, pad 4 is NOT connected to the non ground pin of the capacitor:

enter image description here

EDIT: This is the symbol of the IC: enter image description here

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  • \$\begingroup\$ Look at the symbol and make sure there isn't an invisible pin, or a duplicate pin 4. Also check for a stray track or something hidden under the pad in pcbnew. \$\endgroup\$
    – Hearth
    Aug 25, 2023 at 23:18
  • \$\begingroup\$ @Hearth Thanks for the comment. I am not sure what you mean... I opened up the symbol but it didn't seem like there was a duplicate pin. I updated the question with a picture of the symbol. \$\endgroup\$ Aug 25, 2023 at 23:23
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    \$\begingroup\$ Did you try running a DRC ? That may point out a crossed trace or net. Did you edit the schematic after starting to route? That could also leave wayward traces in bad positions. To check for a small piece of misplaced trace under a pad go to the side Appearance tool, select the Objects tab, then either switch off the Pads view (eye) or set the opacity slider to get a partial transparent view. \$\endgroup\$
    – Nedd
    Aug 26, 2023 at 2:39
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    \$\begingroup\$ They're both assigned to the same net; I would try removing all the connections to both pads in schematic view, updating the PCB, verifying that the pads change nets, and then re-connecting the pads on the schematic and updating the PCB. \$\endgroup\$
    – vir
    Aug 26, 2023 at 5:40
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    \$\begingroup\$ @vir I did just that and the ratsnest was removed. If you want, you can make an answer so I can upvote and mark as accepted. Thanks! \$\endgroup\$ Aug 26, 2023 at 17:18

2 Answers 2

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They're both assigned to the same net; I would try removing all the connections to both pads in schematic view, updating the PCB, verifying that the pads change nets, and then re-connecting the pads on the schematic and updating the PCB.

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Look at the middle picture. There is a line with "GND" just above it. It is possible that this line got named GND. To test this idea there is a button that selects nets. Select the pin3 net and all lines with that name will light up. If pin3 and 4 both light then you know the problem.

enter image description here

It is very likely that while editing the PCB you left a very short trace under pad3 or pad4. You need to turn off the pads to see what is under it, or move the IC and look for a very short trace left behind. The extra trace will have a net name of GNS or the net name of the trace on pin3.

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