Custom pad using DXF import


#1

G’day,

I’m new to footprint editing using KiCad, and I’m having some trouble putting together a non-standard pad for a component. The pad in question is shown here:

I’ve created the pad in FreeCAD, per the dimensions shown above, and imported it as a DXF in KiCAD:

EDIT: I can only post one image for some reason, I’ll add the next two images in subsequent posts below.

A couple of issues/questions:

  1. The DXF appears to be a wireframe only; do I need to apply fill in FreeCAD or can this be done in KiCad?
  2. Is F.Paste the correct layer on which to import the DXF?
  3. When I view the imported pad in 3D viewer, the number of segments in the arc is drastically reduce (see below). What’s the issue here/is this normal?

EDIT: See third post for this image.

Any guidance here would be great!


#2

If you use kicad stepup you should ve able to directly export it from freecad to a footprint


#3


#4

There might be a better solution available. Take a look at my dfn/qfn generator script: https://github.com/pointhi/kicad-footprint-generator/pull/149

And a heads up: the drawing you copy is the “lead” of the package. The pads will not look the same as this would result in 0 fillet even if every measurement is at nominal. (Most likely negative fillet if any dimension has a bit of tolerance)

You should look at the suggested footprint to determine pad sizes. If there is none then you will need to rely either on industry standards or expirience


#5

Thanks Rene, much appreciated.

As you stated, I somehow got the package detail confused with the recommended footprint. I’ve gone with an industry standard QFN footprint, as a recommended footprint for this particular IC is not available from the OEM.