I am new to Kicad and have completed the tutorials I found online. I am using Kicad to design a PCB as part of my masters thesis.
I have the following problem, I have a symbol that contains 3 units. Unit A has 19pins, Unit B has 19 pins and unit C has two pins. I also have the corresponding footprint as a file in my library and its working and looks as expected.
Now my problem is, that I dont know how to assign the footprint to that symbol, as each of the units demands their own footprint to be assigned, otherwise I get an error message when updating the PCB saying that not all components have a footprint assigned.
However if I assign them all the same footprint I just get the footprint 3 times, containing the pins of all three units each but one footprint has only the connections from unit A, the other the connections from B and same for C.
I downloaded the footprint and symbols directly from the distributor for Kicad and except of the assigning everything works well.
To summarize: I cant figure out how to assign a 3 unit symbol the corresponding single footprint.
If you need any additional information I am happy to provide them.
If you are assigning the footprint to the symbol in the library you could look at a multi-unit symbol like the 74LS00 to see how it’s done. There is only one footprint field to enter.
If you are assigning the footprint at schematic time, then make sure you give the same Reference to all the units that share a chip on your board, e.g. U1A, U1B, U1C, and again there will be only one footprint field to assign. Otherwise you are asking for more than one chip. Did you select Annotate Schematic? You have to edit the Reference field yourself. BTW, the symbol must have the All units are not interchangeable box ticked.
Priotrs remark dos look like it’s the most logical explanation of what is going on.
The most logical would be if you zip the project and upload it here. Unfortunately you do have the rights to do so yet as a new user. You either have to spend some quality time reading (and maybe answering) posts, or you have to be bumped up a level by @moderators
I am not 100% sure how to verify this but when I check the symbol properties it says ‘Number of Units: 3’ and the box with ‘All units are interchangeable’ is NOT checked.
I checked what it looks like with the 74LS00 and there is indeed only one footprint field.
With my symbol however, there are three distinct parts appearing in the run footprint assignment tool. I did select annotate schematic. Another thing that is strange is when I edit the reference for example to U1a, U1b and U1c it changes to U1a1, U1b1 and U1c1 after I click annotate schematic.
In the footprint assignment tool I then have the three single parts that demand a footprint (here I selected the footprint for every part):
U1a1 - UEC5-019-2-X-D-RA-1 : UEC5-019-2-X-D-RA-1 : UEC5-019-2-X-D-RA-1
U1b1 - UEC5-019-2-X-D-RA-1 : UEC5-019-2-X-D-RA-1 : UEC5-019-2-X-D-RA-1
U1c1 - UEC5-019-2-X-D-RA-1 : UEC5-019-2-X-D-RA-1 : UEC5-019-2-X-D-RA-1
Ok I think I fixed it with your help guys, thank you very much for your input everyone.
The problem was that when I run the annotate tool it didnt understand that U1a, U1b and U1c belong together somehow. When I changed them all just to U1 they appeared as 1 symbol in the footprint assignment tool and it worked!
You should edit the Reference field to just U1 (in general just a number), and the A, B and C are set on the instances of the units appearing in the diagram. When you have succeeded there will be only one symbol to assign a footprint to, U1. Here’s an example from my schematic:
It contains the A and B (power) units of U4, a CD4060, and the A, B, and C units (of A-G) of U1, a 74LS14.
