VSS versus GND connection on PCB

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Hi,

I am very new to Kicad and have been looking at some of the “Made By Kicad” designs.

I downloaded the project file for the ATMEGA_328_Motor_Board as an example and then unrouted the board so that I could see how the different routing operations work.

I noticed however that the VSS nets and GND nets were connected on the ratsnest but could not be physically connected via routing. This makes sense because they are not tied together on the schematic.

So why are the nets connected? Specifically P13 pin 1 and D8 pin 2.

Almost seems as if Kicad expects VSS to be connected to GND?

Thanks

Regards Graeme

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If you look closely you’ll find D7 (B.Cu) sitting right behind D8 (F.Cu).

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The Ratsnest doesn’t differentiate between footprints at the front and back. So if you place pads with different nets right on top of each other you get what you observed.

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Ah, great thanks. Completey missed that.

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A handy tool is “Highlight net”. Click on a pad and all pads, vias and tracks in that net are highlighted. Also works on unconnected pads. I find it very useful for checking unexpected connections.

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