Splitting nets for different trace widths

Schematic
1

I know this is not a new question, but the answers provided no longer work in the new version of KiCAD.

If in one part of the circuit there are high currents and one wants wider tracks. If those tracks are all part of the same net, one can do that using Design Rules and add a new net class with wider traces. Then one can move these nets to the new net class.

However, sometimes only part of the net needs wider tracks: for example, the same net supplies high and low usage elements.

I would like to split such nets and use a different track width for each part. I have seen on the internet that this is possible with net ties. However, there are no net tie footprints in the new version of KiCad.

Also, these net ties should not raise issue with DRC control, even if they are under another electronic element.

So is it possible to effectively split nets to achieve different track widths for the same net?

2

NetTies are still the current solution to this.

I just checked and both schematic symbols and footprints for netties are still present in:

Application: KiCad Footprint Library Viewer

Version: 5.99.0-unknown-c33b2cfa8d~128~ubuntu20.04.1, release build

Libraries:
	wxWidgets 3.0.4
	libcurl/7.68.0 OpenSSL/1.1.1f zlib/1.2.11 brotli/1.0.7 libidn2/2.2.0 libpsl/0.21.0 (+libidn2/2.2.0) libssh/0.9.3/openssl/zlib nghttp2/1.40.0 librtmp/2.3

Platform: Linux 5.4.0-73-generic x86_64, 64 bit, Little endian, wxGTK, xfce, x11

Build Info:
	Date: May 17 2021 08:36:20
	wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
	Boost: 1.71.0
	OCC: 7.3.0
	Curl: 7.68.0
	ngspice: 31
	Compiler: GCC 9.3.0 with C++ ABI 1013

Build settings:
	KICAD_SCRIPTING=ON
	KICAD_SCRIPTING_MODULES=ON
	KICAD_SCRIPTING_PYTHON3=ON
	KICAD_SCRIPTING_WXPYTHON=ON
	KICAD_SCRIPTING_WXPYTHON_PHOENIX=ON
	KICAD_SCRIPTING_ACTION_MENU=ON
	KICAD_USE_OCC=ON
	KICAD_SPICE=ON

Which is 5 day’s old now.

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3

I use KiCAD for Windows, version 5.1.10, which was supposedly released in May 2021 and I just don’t see net ties… I see netties in schematics but no netties in footprints. Maybe I don’t know where to look?

Untitled
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4

V5.1.10 is currently the latest & greatest among the stable versions of KiCad :slight_smile:

The NetTie library should be listed right between MountingHole and OptoDevice

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image691×419 66 KB

However, I see lots of plural names (ending with an “s”) in your library setup, and that means you are working with footprint libraries from KiCad V4.

Another indication would be rectangular pads on lots of footprints. A lot have changed to pads with rounded corners in KiCad V5.

https://forum.kicad.info/search?q=library%20management%20category%3A19

5

Yes, I found the library in the KiCAD folder and added it manually.

This obviously remained after I installed KiCAD 5 over KiCAD 4. How can I update to latest libraries? Maybe I should completely delete KiCAD and install it from the start?

Additional problem is that if I put nettie under another element, I get courtyards overlap error. Isn’t it possible to make those net ties under other elements?

6

See the title of the dialog window – you are using the github plugin for libraries. It has been deprecated and even removed from the later development version 5.99 (future v6). You should replace the fp-lib-table (and sym-lib-table) from the configuration folder (see Where are the configuration files (settings, library tables)? and I had KiCad 4 installed previosly. Now i updated to v5. Now i have some problems with the library setup).

But WARNING: changing this will probably mess up your existing projects, at least for symbols. Footprints are safer because they are embedded in the board files.

7

Where did you get KiCad and how did you install it?

This stuff with old libraries and the github plugin should have been a thing of the past, and yet, in another post you state you’re working on your fist KiCad project.

8

It would be enough to test v4 once and years later install v5.1.

9

As eelik pointed out, I just tested KiCAD few years ago. This week finally decided to design my own PCB, because I finally got a project that was worth designing PCB. I downloaded KiCAD for Windows from https://www.kicad.org/.

So now I have this mess. What do you suggest - completely removing KiCAD and make a completely fresh installation?

10

If you don’t need to keep any user settings – and it looks like you don’t – just delete %appdata%\kicad. Then start v5.1 again, and it starts from scratch.

11

By the way, I also kind-of solved my problem by creating my own net tie that does have courtyard. I simply copied everything but courtyard into my own definition of net tie. Now I can connect high current and low current subnets under the elements…

12

It worked. I only had to reload my own schematic and footprint libraries and everything is fine. But I will not reload footprints because new fancy pads would require redrawing majority of tracks…

13

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