I have several level shifter chips with unconnected ground pins, like for instance SN74AVC8T245PW, it has 3 grounds and 3 power pins. Is it possible to fix those connections in the layout.
Or is it necessary to fix libraries.
Here is one example of the problem
Layout shows that grounds are unconnected
Edit: There are also several SMD chip with ground connections but no ratsnest is shown, but that is an layout problem, I think.
Your U17 has 24 pins, while your U5 has 14 pins.
It is relatively common to use “pin stacking” in KiCad’s library symbols.
If you look closely at pin number 11 of your U17, you see some bluish text. That are the pin numbers of the other stacked and hidden pins.
For the ratsnest issue.
You’ve turned visibility of zones off. I assume those other GND pads are connected via the invisible zone.
Thank you. I have to check how many pins my ICs have later, I can’t do it now.
Layout issue is strange, I think I have not connected those pin anywhere yet. But that too has to wait a bit. Is Kicad creating creating vias automatically?
I could not resist and came back to the Kicad, allthough its getting late. I edited the library symbol and managed to get the GND pins separate and visible, it was surprisingly easy, nice.
About Layout problem, I think I know the problem, I am sorry but I don’t think it is necessary to put this in correct forum. There are remains of copper GND plane below the IC. Some pins tough the GND and are happy with that, and some others need routing. It looks like some pins are shorted to GND too. I have to create a new top copper. Do you know how it is done?
Read KiCad’s manual?
Or just press b to re-calculate internal zone geometry.
If neither of those two methods work, then post a screenshot with the zones actually turned on so others can see what it looks like.
B did it
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