DRC: Clearance issue of a default footprint

I hereby certify that I am not simply asking someone else to design a footprint for me.

here what’s occurring with that footprint (default one)
Capacitor_SMD:C_0201_0603Metric_Pad0.64x0.40mm_HandSolder

here the faulty footprint

Application: KiCad Schematic Editor x64 on x64

Version: 7.0.1, release build

Libraries:
wxWidgets 3.2.2
FreeType 2.12.1
HarfBuzz 5.0.1
FontConfig 2.14.1
libcurl/7.83.1-DEV Schannel zlib/1.2.13

Platform: Windows 11 (build 22000), 64-bit edition, 64 bit, Little endian, wxMSW

Build Info:
Date: Mar 11 2023 03:41:46
wxWidgets: 3.2.2 (wchar_t,wx containers)
Boost: 1.80.0
OCC: 7.6.2
Curl: 7.83.1-DEV
ngspice: 39
Compiler: Visual C++ 1934 without C++ ABI

Build settings:
KICAD_SPICE=ON

Not a faulty footprint, it’s just too small for the clearance you’re using. You will need to decide if you can make your minimum clearance on that net smaller, or if you need to use a different footprint.

An 0201 capacitor is pretty small, it doesn’t surprise me that the clearance between pads is small enough to cause problems with reasonably large clearances.

I need a 0603 for the capacitor

I’m not exactly sure what you’re saying in this post - are you saying you need to use that footprint?

If so, you will not be able to use a 0.2mm clearance for any net that needs 0201 (0603 metric) caps. You’ll need to change the clearance on the Default netclass to 0.18mm or smaller, or assign that net to a different netclass with a smaller clearance.

Sometimes you can edit the footprint to have more clearance, but that would likely compromise the manufacturability of your design. I don’t recommend it without knowing more about DFM for 0201 caps.

ok I changed footprint …

3 times bigger than 0201 and 6 times bigger than 01005.

I’m not sure if you just corrected selection to 0603 or changed to something else.

I went into the Schematics, changed the footprint with a 0603. that’s it.

So I updated it and positioned.

HOwever the name of the “”“wrong one”“” is

C_0201_0603

That 0603 inside the name tricked me :-/

It’s C_0201_0603Metric if you don’t crop off the “Metric” part

This dual-naming is not unique to KiCad, it’s just an unfortunate fact of life in passives.

e.g. digi-key:

image

In 2017 when I moved to KiCad I decided to use only metric. So my main footprint I use for resistors has the name: 1608. But even years passed I still think of it as 0603.

in all projects I used metric … and the size was correct. … but then I discovered today that 0603 is contained also in other cases … and ok … just I changed it …

I am thinking instead of changing it just don’t use the “HandSolder” footprint use the one above, the pads will be a bit smaller but you might not get the error and I have found that the component can still be soldered by hand if you have been doing it for a while. It seems to me that the hand solderable pads can be very generous. This of course is subjective but it’s just a thought :smiley:
:mouse:

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I guess I’m the only person who has run into this error and wondered why it exists while also selecting the correct footprint? That makes it even harder to track down an answer, but I gleaned what I need from this post.

I think there should be some sort of note attached to the DRC error report when it’s about two pads on the same default footprint. It’s not immediately obvious that the default clearances and the default footprint are incompatible with each other. It seems counterintuitive to make such a contradictory situation the default setting without some note attached.

It’s a very hard balance to keep . . . there are other things to consider, do the defaults work with your chosen PCB manufacturer ? I think I’d rather have DRC errors/warnings part way through layout than rejection from the PCB manufacturer at the point when I think my PCB’s layout is done.

The defaults are just that, defaults that might work for you, really you should be adjusting them to your project’s individual needs with the capabilities of your PCB manufacturer in mind.

Alternatively choose components with footprints that are less challenging to work with.

What is default footprint?
I have never heard about such something.

It’s your job as a designer to select design rules that are appropriate for the circuit you’re designing and the parts you’re using. If you pick a footprint and KiCad’s DRC complains that the footprint violates your design rules, that’s a hint to you as the designer that either your design rules are inappropriate for your design, or the part you chose is inappropriate for your design rules. That’s the point of DRC.

To use an example, consider a fine pitch BGA part. If you need to use this part, you’re going to be paying extra to your fab to get finely pitched traces and spaces on your board. KiCad’s default design rules will be too coarse for this board, and with the default design rules you’ll have clearance violations on the BGA footprint.

Should KiCad’s libraries not include that BGA footprint, or any other parts that don’t work with the default design rules? Of course not - it’s a perfectly useful footprint, but the designer needs to choose a reasonable minimum clearance.

KiCad’s default design rules are just defaults. They’re intended to be reasonable for many situations, but they are just defaults. It’s up to you to make sure they make sense in your design and adjust them if necessary.

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I suggested nothing about not including footprints or DRC checks or anything of the sort. I merely suggested an extra option, one that’s not even an option, just a note so that people who don’t know everything about kicad don’t wind up confused and searching the internet for answers because two default settings conflict with each other.

Let’s try to avoid semantic games here. The included global footprint library here counts as a default option. Every footprint and symbol is jam packed with default settings. Let’s just make them play nice together or at least let us know why they’re fighting (on the same component that’s packaged with kicad by default no less). I know, it’s a controversial idea. I just thought I’d throw it out there since I had to go web searching for it, and clearly I’m not the only one.

As far as choosing less challenging footprints… In my opinion they’re all equally challenging. I place the footprint and it gets a part put on it. The size doesn’t make it challenging beyond one’s ability to solder it to the board, and I find there are no parts I cannot solder in place with enough patience. I guess we all have different ideas of what’s challenging.

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I realize now I’m not on the kicad development forums, so I suppose I should have saved my feature recommendations for the developers’ forums. Enjoy each others’ company, you’re a very pleasant bunch.

I think it’s the correct place where to post this. I see many devs following this forum. And in the past, I saw also solutions taken. Not without prior discussions eh … this should also be clear, but some solution was implemented.

I didn’t mean less challenging to you I meant less challenging to your PCB fabricator. If they require 0.25mm clearance and you are using footprints that have features 0.2mm apart then your fabricator cannot make your PCB.

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