Trying to unite traces, kicad doesn't allow me

Hi everyone, I am trying to unite the signals of three inputs, but kicad doesn’t allow me.
I changed the schematic symbol pins as bidirectional and passive to check if i can do it,… but it doesn’t work.

It happens too with a specific component, so the question here is: Can I unite different traces in a node somewhere?

Thanks in advance

Can you post a picture of the issue? Are you getting a error in the ERC?

…different traces like different net names? they must be kept separated by definition.
There is a component called net-tie that enable you to do so (if you are sure that that is what you want to do).

Misleading…

You can have multiple traces on the same net, if wanted.

I often load One Pin (on an Arduino) to get higher Current. Generally, about 40mA per pin so, 1 pin/Pad drawing from 3 pins yields 120mA.

Example screenshot show individual pins/pad and, combined pins to One Pad. No DRC errors or warnings.

Notice the Net Name on the Traces

ADDED: Don’t mistake Kicad’s ability to hookup to multiple pins as an Endorsement for all pins. Best to Not mix Ports (different Arduino’s have different Ports/Pins).

The ‘keyword’ was “Gennerally”. And, though 40mA/pin is Max, always best to keep loading down to about 30mA/pin

yes, that’s correct.

I interpreted the question

like:
can i unite traces (with different net names) in a node somewhere?

AFAIK no, you can connect traces only if they have the same net name,
or you can ‘trick’ it using a net-tie component.

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For me connecting inputs means driving 3 inputs from one source.
There should be no problem with it.

What does it mean?
May be your connection at schematic is not done. Sometimes people change schematic grid and they think they connected pins but they didn’t.

Are you thinking that you can just “add some wires” to the layout? You have to add them in the schematic first, otherwise KiCad will prevent you from joining distinct nets.

That’s the advantage of KiCad keeping the schematic and layout at parity. If your schematic is correct, you have a high degree of confidence that everything is wired up in the layout as you specified.

You don’t want to hear about the bad old days when I wired up valve circuitry and had to double check that the wiring was as specified by the schematic. Took out a few HV rectifiers before I learnt to be more careful.

I’m seeing a lot of speculation here about interpretations of what the actual problem is or could be.
I don’t like guesswork and believe it’s giliroller’s task to give more clarification about what he’s actually trying to do.

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Hi again, thanks for your fast reply,… I realize that i didn’t explained myself well…
clarification:
-The wires are already connected in the schematic in eeschema
-When I try to do the same in PcbNew, when i put the mouse over the other trace, PcbNew doesn’t allow me to unite those traces jumping to the side of the trace that is already drawed

Sorry for my english :slight_smile:

Also I realize that there are not names in my net, not at least that i see with my knowledge as a new user of kicad.

Thanks

There are junctions (green circles) between the wires, I checked and they are connected, also I know it because I had to change the schematic symbols to bidirectional and not just inputs to avoid conflicts when using the tool “perform electrical rules check”

Just tried with the net tie simbol in eeschema but still cannot connect the traces in PcbNew,… something I am missing but I can’t find what…

add pictures, please, makes understanding easier!

Which way you get footprints at PCB?
Do your PCB is synchronized with schematic. May be these are two separate things one not knowing about the other.
There is a function (one of icons at top toolbar) “Update PCB from schematic” you should use.

In “Tools”, top function.

I do update PCB from schematic every time i change schematic

I also labelled the nets with no positive result…

You write:

And then you post a screenshot of the schematic without labels.
Which also makes me doubt your other posts.

In KiCad you can also mirror schematic symbols (with either the X or Y shortcut key). When you mirror J4 (In Y direction) then you can connect both wires without them crossing each other.

I think you need a beginners course for KiCad. I do not know wat is a good source for that at the moment. It also depends on what works best for you. Do you prefer text or video?

Maybe this is a reasonable starting point, (even though it’s made for KiCad V5, so there will be some differences).

I suppose you didn’t read even Getting Started?

I saved different versions, and the one i sent was the original

Nice tip, thanks

The first I did was to follow the course of digikey on Kicad,… maybe i shall go deeper in the study of this program,…