Combining multiple pads in a single shape pad

[AB007]

Hi, I have a footprint that contain pads with multiple numbers that overlap (I use Kicad 5.1.6). Can you please let me know the best way to combine those in a single pad with custom shape (eg. pin1 and pin10 combined in a single pin with number 1)? I’m not sure if the best way is to have multiple pins with the same number in terms of global thermal property; there is a way to combine actual pins?

Thanks,
Andrei

[Ralph_Loveday]

Posts here suggest combing pads with the same number.
Also, the experts here will suggest updating to 5.1.9 to take advantage of the latest bug fixes.

[Rene_Poschl]

Easiest option is to just give the overlapping pads the same pad number.

Alternative is to use polygon pads (complex shapes) but they are less intuitive to make and can not use thermal spokes connection to copper planes.

[eelik]

@Rene_Poschl

can not use thermal spokes connection to copper planes.

In the unstable development version 5.99 they can, though.

[Rene_Poschl]

The user specifically told us they are on v5.1.6 so the feature set of nightly builds is irrelevant here.

[eelik]

Sure, but it doesn’t hurt to advertise what lies ahead. Do whatever you want with that information.

[paulvdh]

I also make some advertisements for KiCad-nightly V5.99 when applicable, but here it does not seem very useful.

I found Ralph’s answer quite adequate and that is why I did not respond earlier.
I do wonder about the footprint though. It seems unlikely that the screenshot is as advertised in the datasheet.

For examples, open the Footprint Editor, and then have a look at any of the footprints from the default libraries with the word “thermal” in them (you can search for that in the FP editor) and study them. Multiple overlapping pads are normal practice in KiCad.

[AB007]

Thanks all for the answers. it is a weird package but is exactly what they advertise in the datasheet. Please see here: https://www.ti.com/product/LMR36506-Q1

The reason why I’m using KiCAD V5.1.6 is because I use High Serra on my mac and this is the latest version supported under this OS. The upgrade is complicated so I plan to do-it when the 6.0 stable version will be available.

Thanks again,
Best Regards,
Andrei

[paulvdh]

@AB007

but is exactly what they advertise in the datasheet.

Euhm, not really.
From the datasheet you so kindly linked to:

There are two significant differences.
First, the datasheet has no mention of pad numbers above 9, which overlaps with the advise given here before.

Second:
The datasheet recommends rounded corners for the pads. (Also supported by KiCad). This is quite important with such small pads. The rounded corners are mostly important for the solder stencil. Solder paste has a bit of a tendency to stick into corners of the stencil, and when there are no corners, it won’t stick. This results in an easier release of the solder from the mask, and a more uniform amount of solder on the pads, which improves production reliability.

[AB007]

@paulvdh You mean something like this?

Thanks,
Andrei

[eelik]

That looks good. -----