Electronic – How to have both PCB components and external components in the same KiCad project

kicadpcb-designschematics

I am using Kicad (5.1.4) and would like that the schematic contains all the component wiring required for a PCB board as well as the wiring for components external to the PCB board (such as switches, displays etc.).

Previously I have set up an additional project for the external wiring. However, trying to manage both projects (e.g. ensuring consistency) is error prone.

I have tried not associating footprints with the external components. This seems to work in that Pcbnew does not attempt to layout the external components – meeting my goal – but still comes up with errors about the missing footprints. Secondly, it does not seem to be a “transparent” method in that it is not immediately obvious from the schematic which are the external components.

Is there a better way, for instance using hierarchical schematics?

Best Answer

You can do a few things here. One option is to use the graphic drawing tools to include off board components in a nice way.


Another is to use a strange KiCad feature mostly used for power symbols. If you add a symbol and prefix its reference with "#" then KiCad does not include that symbol in the netlist (a symbol of that manner does not get a footprint)

You can then use normal wires to make connections to this off board symbol. For example if you have a connector then you might want to include the plug as an offboard connection, the cable by use of wires and the off board component itself.

One would hope that v6 will have a more intuitive alternative for such a feature. (example an explicit symbol setting for virtual or offboard components and possibly a separate setting for inclusion in the netlist and inclusion in the BOM)


In the professional world system level drawings are however mostly created in separate tools like eplan (an open source alternative would be https://qelectrotech.org/) This is the way to go if your system is has more than one PCB or if the offboard cabling is too complex to realistically be shown with the limited tools of KiCad.


I now also made a more detailed writeup on the forum FAQ https://forum.kicad.info/t/off-board-components-in-kicad-5/22286