Hello !
I’ve a schematics with 3 parts on the same sheet : An amplifier with various through the hole components, an input switch attenuator for which I do not need a PCB because it will be wired on the switch, and a function switch (power switch, battery testing, and “power on” ) for which I need a different PCB.
I’ve assigned the foot prints for all the components (except the one irrelevant PCB wise like the batteries) and generated a netlist.
But if I import this netlist in the PCB editor, all component show, even the one I do not need.
Question by a real newbie : How do I make two PCB from a set of 3 schematics parts ?
Many thanks in advance for your help and advice !
Have a nice and bright day !
The “official” answer is, KiCad currently supports only one PCB per project. Which means you have to split your project into two projects, and the simplest way to do that is to copy the whole project directory, and then delete in each directory the parts you do not want on the PCB for that project.
Another possibility is to put all the parts you want on a single PCB, and then cut or saw the PCB in two after etching. If you want this, then reserve some room on the PCB for the width you are cutting.
To prevent a component from being put on the PCB, you can omit it’s Footprint, but this will generate an error. It’s better (but also a hack) to put a hash sign in front of the the annotation of a schematic symbol (Also Called RefDes from “reference desginator”).
For example, in the screenshot below, the 180k Ohm resistor will not be placed on the PCB:
A recent post about experimenting with multi-pcb projects:
which also links to my older Idea:
But I am under the impression that georgesgiralt does not have much experience with KiCad yet, and my earlier (and simpler) answers were more suited at the moment.
Hello Paulvdh,
Yes I have experience with Kicad ! This is my second project ! (the first one being the one associated with the French tutorial from Mr Perronin on Youtube…)
And I often used, at work, the idea of a master document linking to a lot of smaller documents each one being written by different persons. So your concept of hierarchical project rings a bell. But it will be overkill IMHO in this case. I prefer your tweak with the # sign in front of the component reference for avoiding to place them on the PCB. After all there are just a bunch of resistors and a capacitor.
BlackCoffee suggested I do not assign a foot print to a component I do not want in the PCB. This works well for the batteries in my project or with the switch in the attenuator but is more difficult and prone to errors for the resistors. I’ll try this after my coffee when I’m fully awake
So I’ve got solutions from drawing to PCB, and I can find one for cutting the PCB in two parts. Maybe using the “Edge.cuts” layer to signal the maker I need two parts ?
Thank you all for your help ! It is very valuable to me !
P.S. : I still have to check the post from BlackCoffee for multiples PCB in the same project.
As you can see, I plan to have wires going to the two 9V batteries, two wires from the amplifier output and two wires going to the 29 µA meter. The resistor and adjustable are meant to adjust the reading to give “1V” reading when I test two fresh 9V batteries nearing 10V each. So I would know what the average voltage is on the batteries.
When I import the Net list on the PCB this gave me this :
As you can see, on the left there is the amplifier part of the schematics and on the right the little part with the switch.
Question : Is it possible not to draw anything between the condenser on the left and the J17 pad ? Is it possible to suppress the link between the two part of the PCB ?
(I plan to route the two parts of the circuit in two different “circuits” then duplicate the PCB file and suppress one part on each duplicate before generating the Gerber files for the PCB maker. I wonder if this is doable…)
So i would like your advice and guidance on this, as you see, I’m a Kicad expert
Many thanks in advance !
Have a nice day !
That said, the only connection between the two groups is the GND net. So to seperate them you could use “GND” for the left part and “AGND” on the right part.
If you are trying to be cheap and get this as one design from a manufacturer it may not be possible. Some which make cheap prototypes for a few $ for n boards handle it as two designs when they notice the attempt. Some people circumvent that by adding extra connections which make them look like one design.
It looks like that is the “ground” or 0V reference. Use a different GND symbol between the two schematic sections. And take note of the advice from others to watch out for PCB houses that will want to charge you for combining two boards into one design. Not all board houses will, but some will.
Probably doable, but awfully kludgy. I’d just do the two circuits as separate designs to make things simple in the file-management aspect.
