How to use the jumper symbol

I think you are barking up the wrong potato. wait… (??)

I don’t know why kicad have jumpers when it is so difficult to implement them. I have an idea which may work but have not tested it yet.
You take 1 jumper, say a solder jumper, and connect one end to a track from, for example, an op amp output. This is the solder point at this end. The other end of the jumper is not connected because this is attached to the jumper wire. Then the connecting wire at the other end is connected to another jumper. Again one end is left unconnected and the other end is connected to a track from perhaps another op amp. This then is the solder point at the other end.
Each unconnected end of the jumper can be referenced the other end of the jumper wire using the component editor.
If you only use 1 jumper you are going to have to draw a track on the schematic which will later be seen as a track on the circuit board.
In all of the above I am referring to using a jumper on the schematic.

On a schematic you don’t need jumpers for this. Just draw a wire from the first point to the second. If the wire crosses over other wires then it doesn’t matter. They aren’t joined unless you explicitly want them to be.

@petercl14

Here is another section of a Schematic showing how jumpers are used:

Jumper 1 shows that there is a jumper somewhere between R5 and Pin5 of U2. This is a schematic, so it does not show where or why the jumper exists. All it shows is that there is a jumper, that on the PCB, will give a break in the track between R5 & U2B.

Jumpers 2 to 5 would serve a different purpose. These would act like switches… select 1 of the 4. In this case there would probably be some written instructions as to how these jumpers should be used.

NOTE: On the schematic, jumpers have nothing to do with any wires crossing other wires, they are treated just as any other symbol on a schematic. Which wires are soldered to which pads, how when and why, have nothing to do with the schematic.
There is nothing very difficult about implementing jumpers on a schematic, you just place them and attach wires.

I think we have an XY problem here.

My hunch is that OP wants to make a single sided board using jumper wires for unavoidable crossings, but is obsessed with putting a jumper symbol in the schematic. But I don’t know until they explain more.

Here are typical footprints assigned to jumper symbols. First a pinheader jumper without the shorting thingy.

pinheader_jumper

Next a solder jumper that is soldered before first use.

solder_jumper

Yes, agree.
That is why I posted the schematic above. :slightly_smiling_face:

My jumpers 2 to 5 are represented by @retiredfeline s first 3D image. 3 jumpers have the “shorting thingy” omitted, the 4th has it fitted.

For the jumper no.1, if I wasn’t sure of the distance between the pads needed, I would not bother creating a footprint for now. Instead, I would just place two orphan pads on my PCB, draw up the PCB and use the orphan pads to find the correct distance required for the final result. When I was happy with the result, I would create a footprint consisting of two pads (the required distance apart) plus a graphic line on the silkscreen layer joining the pads. I’d then delete the orphan pads and replace with the new jumper footprint that I had assigned to the jumper symbol.

How with only 1 jumper will the wire connection no where to stop? That is your other pad. Do you somehow give the jumper instructions as to where the wire should finish. How would you do this?
It may be possible to do this with another jumper at the destination of the jumper wire but I don’t see how you can do it with one jumper.

Are you saying that if I cross tracks in the schematics they wont cross in the pcb editor. Will they be shown then as a dead end of the track on the pcb editor? Then having to manipulate the symbols on the pcb editor to make them join up again?

No, generally those two “ifs” are unrelated. You can have either one without the other. BUT. When you do pcb layout you may find that you want a jumper to jump one track over one or more others. You can then add that jumper to the schematic. But the schematic would generally not show that the jumper is spanning those tracks. (A schematic in which a jumper is jumping over certain wires would probably be unclear. You usually do not want schematic wires crossing through a component. A jumper on the schematic is a component.)

Digipot SEPIC 12-11-2021b.zip (519.8 KB)
I have attached a design of mine from 1-2 years ago. You can see that it has jumpers in the schematic and on the board. The jumpers are there to jump over tracks, but the schematic does not indicate the tracks being jumped over. You may need to up convert…I think this was probably designed in version 5.99.

Or just design the schematic without jumpers or h******s (sorry must not mention the taboo word) and layout on a two layer PC.

For anyone who cares enough to open up my zipped project (I do not blame anyone if you do not care enough) you can see that mine is a 2 layer board. I used jumpers because I wanted to keep the ground plane more solid than it would have been if I used bottom side tracks.

“Wire U using jumpers?” :slight_smile:

BTW I used to be skeptical of any need for jumpers to be oriented in angles other than 0, 90, 180, or 270 degrees. But in this design I found it helpful to use some odd angles. Perhaps this is just consistent with my tendency to produce layouts that look like I was drunk when I did them. (I was not.)

I’m not at my computer so can’t open your project; not all of us have KiCad open all the time ready to pounce on questions. The fundamental issue is OP seems to think that if you want to have wire jumpers then you need jumper symbols.

Just draw the schematic as normal and then lay it out for a 2 layer board. It may be that no crossings are required to keep all tracks on one layer. If they are tracks required on the second layer indicated by uncompleted ratsnest lines then go back to the schematic and add pairs of THT single pads where crossings are required. Hopefully there will only be a few. Then submit the order without the 2nd layer. No jumpers needed on schematic.

Or just order 2 layer boards. The don’t cost any more than 1 layer boards these days.

No need to make bridges until you have to cross them. :wink:

It seems it is the position of the dot which is important. On the final printed circuit board you would just get a track from 10 to the dot at jp2 pin2. At the other end just a track from the dot to 8.
Now I see it. Any connection between jp2 pin1 dot to 8 dot would not be shown as a track on the printed circuit board.

Only at the kicad forum are people trying to make a hammer out of a shovel) all in one heap)) jumper is jumper)) jumper is a jumper and these are different things)) from the word at all… Usually, for those places where a connection break is required, a resistor 0 om… Jumpers with the ability to quickly break or connect the track are called jumpers… Jumpers in the classical form are usually used to strengthen power lines, such as tinting a track… There are also current-measuring shunts in the form of jumpers, but this is another topic…

If you look at the jumper symbol, you will note that it has two pins. When this jumper symbol is converted to a footprint, it will also have two pads. On the PCB, one pad will connect to one end of the jumper wire and the other pad will connect to the other end of the wire, just like a resistor or capacitor has two pads in a footprint.

The position of the pads for the jumper are often difficult to determine until you know how many and what thickness the tracks that the jumper needs to cross are. This is explained in my above comment.

The same reasoning applies to a Through-hole 1/4 W resistor. Say you have a footprint that is 7.62 mm between pads, but you wish to run 10 tracks under that resistor. Instead of using the 7.62mm footprint, you may use a larger length footprint of 15.25mm between pads. You are using the same resistor, just more lead is showing on the PCB.

Yes, but in a schematic there are no tracks, there are only wires. As I stated wayyy up:

All a schematic does is show the components that make up a circuit design, and the way these components need to be attached to each other and the outside world.

No, there are no dead ends, unless you forget to join a wire to a symbol.

There are no symbols in the PCB editor. There are only footprints.

Footprints and tracks on a PCB
Symbols and wires on a Schematic
Components and board on a 3D image.

A dot represents a junction. All wires meeting at a junction are joined together. If there is no junction (dot) the wires are just lying on top of each other.

and also to the left hand resistor below.
You would also have a track from pin 11 to pin 2 JP5 and also the right hand resistor.

No, there would be a track from pin1 JP5 to pin1 of JP4 & 3 & 2 and Pin 8 of the comp. and VCC. Take note of all the junctions.

No. All wires will show as tracks and all wires with junction dots will show as connected tracks. Wires crossing each other , without junctions will show as tracks that are not connected to each other, only connected to the footprints. The only places there will be no tracks is between pins 1 & 2 of all the jumpers.

Kicad, being FOS attracts all types of users, from the retired after 50 years in the industry (who cannot, or will not, afford the 5 figure price for a seat in an upmarket commercial product), to brand new, still to find out that a breadboard is not something on which you make a sandwich.

If you are not prepared to show suitable patience when needed, please refrain from posting.

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a jumper as a footprint is not intent to jump over other tracks. maybe that clarifies a bit.

To my view, the easiet to use a jumper to jump over track.
Do a PCB with more layer than your board.
Use one of the inner layer to represent your jumper, (and do only simple straight track on this layer.
Use a via to be the first pin of your jumper wire. then the straight track that represent the jumper, then another via to go back to your board.

If you have a 2 layer board, then select 4 layer in the setup to give you the extra layer to represent your jumper.

The DRC checking will be OK. And kicad will not care if you actually build a 4 layer board, or a 2 layers plus an extra layer that you make yourself with the jumper wire.

Doing that, you don’t show the jumpers at all on the schematic, were they should not be anyway.

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