Pretty, L and M library file

We just successfully started to import component library from a well known distributor site.
Is this for different version of Kicad? Below is from another well known distributor and it is different with pretty folder and then three files inside, L and M.


We are on Kicad version 8.0.1 Many thanks

I don’t really understand your question. My own preference is to use KiCad’s default libraries as much as possible. From what I know, they tend of much better quality then (most?) 3rd party libraries.

And concerning your KiCad version. You should not stick with KiCad V8.0.1. The current version is V8.0.2, and V8.0.4-rc1 has also been released. Increments in the third number are bug fix updates, and these are released approximately once each month. KiCad is being developed very actively, and in a month it’s common that 50 to 100 bugs are fixed. Often more then two per day on average.

These are probably variants of the footprint for different IPC density levels (low/medium/high)

Many thanks. Just googled IPC density and it points to size of extra land protrusion for different situations. Presumably, minimum protrusion depending on level of PCB manufacturing and PCBA / Soldering. Any idea on what level is the norminal-service (not advanced) for PCBWAY making PCB and doing asembly. They say imperial 0201 (0.6 by 0.3mm) size is supported. Trace width and spacing between traces are minimum 0.1mm and perferably 0.15mm. From video on their web, seem for order of initial test debug run, one or few pieces, pick and place are done by highly skilled workers under optical magnification aid. Many thanks


Google says, "Soldering techniques: Many packages can be soldered either by reflow-, wave- or hand-soldering, which usually require different land patterns. For every suitable soldering technique there could be a corresponding footprint variant.

Density levels: IPC-7351 specifies three different density levels for footprints:

Density Level A: Maximum (Most) Land Protrusion

Density Level B: Median (Nominal) Land Protrusion

Density Level C: Minimum (Least) Land Protrusion"
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Many thanks for explaination. We would take your advises to use Kicad footprint for standard size components. Presumably, you ment those with industry standard name, 0201, DFNxxxx, etc.
The component I mentioned is a breakout module. It is a custom PCB with BGA and dozen of supporting parts in a metal can. Googled QFN_90687 and seem not an industary size code? Many thanks

New to KiCad…
An example library part from TI…same device (SO23) but three footprints that look very similar…see the same with other imported library parts…what is the difference ??

ul_TLV61048DBVR
SOT-23-6-DBV_TEX
SOT-23-6-DBV_TEX-L
SOT-23-6-DBV_TEX-M

Thanks
Phil

Sounds like the same question as this topic: Pretty, L and M library file

I’m using one SOT23 footprint and never noticed any problems with it.

When I am designing footprint for devices that each manufacturer suggest a little different footprint I’m trying to collect as many examples as possible and make something that satisfies them all and then use it for devices from several manufacturers.

Most of the differences will be because of the Density Levels mentioned in the post linked to by retiredfeline. For the rest, pads with rounded corners are better, and also recommended by IPC. Always use rounded corners in pads if your software supports it (And KiCad does). The remaining differences are probably just due to the mood of whomever designed the footprint, but there may be special cases with special requirement. Solder turns liquid during reflow and it will conform to whatever shape the pad is. As long as the pads are in the right locations and approximately the right size already 80% or so of the requirements are already met.

What is the historical origin of the term “pretty” for footprint libraries? I just have a footprints folder, because otherwise it just seems pretty silly.

A joke by one of the previous members of the development team.

hah, that’s pretty funny!

Pretty sounds better than “nice” and is quicker to type than “beautiful”? :slightly_smiling_face:

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