I’m a fairly new KiCad user, but I’m pretty happy with it. I am achieving results, which is more than I can say about my previous attempts to learn two other commercial electronics CAD packages.
I need to place a rectangular EMI shield box around some amplification circuitry. The shield, or alternately, shield clips, will be soldered to the PCB, and there will be components inside. I am trying to figure out what the best way is to define my shield.
I would prefer to make a custom footprint for the shield, which would include four pads and the outline of the shield. That way I could drag the footprint around and be assured that the spacing between the pads does not change. What I do not know is whether KiCad will allow me to place components INSIDE this footprint. Will it generate an error?
Alternately, I could just define a single solder pad object, make our of them, and drag around each of them separately. I know this will work, because this is how I define ground plane stitching vias. But I will have to check my spacing very carefully. Every time I move a solder pad, I could mess something up. I think it would drive me crazy.
It isn’t important for me to see the EMI shield box itself in the 3D rendering, I just need to know that the pads are in the right places.
Yes kicad will allow that.
Currently kicad only checks copper layers. (It only shouts if you place two pads or traces of different nets to close to each other.)
And this example is one reason why. Another is that parts can extend beyond the Edge Cuts eg buttons and LEDs. Courtyard collisions would generate so many false positives
You get one “Attaboy!” reward for making your own footprint.
Depending on the extent and complexity of your shielding enclosure, you may find that putting all the details onto the silkscreen uses up real estate that could be used for other things. I often use one of the “technical layers” (typically “Margin”) to show details that won’t appear on the board itself. In your case, that may include things like the location of the access hole where you adjust the trimmer capacitor inside the shield . . . . or the area where a connector penetrates the EMI shield, and must be kept clear of parts (but not necessarily traces) so you can connect/disconnect the mating connector.
Thanks Dale, I made the footprint for the shield, and it seems to have worked. The rendering looks correct. I’ll know for sure when I receive the PCB’s.
I hadn’t seen your post yet. You were right about the silkscreen layer, at first I drew the complete rectangle, but I wanted part labels in the same space. So I reduced the shield outline on the silkscreen to just marking the corners. Next time I will investigate the use of the technical layers.
