I feel like I missed something …
Do you have a net that is called GND? Then it should be listed where
<no net>
GNDA
is listed. If you have a net that is called GND, then could you upload a small example project with that problem?
It is possible that OP connected GND and GNDA so for KiCad they stayed one net with semi-randomly one of names selected as the net name.
Yes did. My project is to create a custom board based on 2 stm32 nucleo boards, so I just took what was needed from their schematic and add some changed but on their schematic there were “earth”, “gnd” and “gnda”.
Anyway here is what you asked :
pcb_gng788-MCU.pdf (255.4 KB)
analog conditioning and current protection circuit.pdf (252.5 KB)
He asked for project, not pdf.
In one of my sheet there is GNDA connected to GND through a 0ohm resistor
It should be not a problem. They should stay being separate nets.
I don’t think I’m allowed to send the project
The question was about
You copy your project and delete, delete, delete checking if problem still exists. Then you send something that has really nothing common with your project.
I deleted as much as I could but now i’m stuck with one issue which make no sense
OT: Do you really want to have a separate net AGND? Wouldn’t it make more sense to use a single GND net?
Creating different GNDs can be problematic for EMC reasons and should be avoided in general (there are some use cases, but they are rare and then you have to be careful. For example you should not route any track above plane GNDA to a place above GND).
The problem with 2 GNDs is that you create a dipole antenna with a IC in the middle that will use this antenna to radiate in a very hard to predict way
I honestly don’t know I just followed the schematic of these boards :
https://www.st.com/resource/en/schematic_pack/x-nucleo-ihm08m1_schematic.pdf (everything beside the connectors CNx)
https://www.st.com/resource/en/schematic_pack/mb1136-default-c04_schematic.pdf (the MCU sheet only)
I wouldn’t have used GNDA nor Earth but only GND if it wasn’t because of these CAD resources
Note : I’m a student
How accurate do you need your analog/ADC parts?
If you use a single GND, still make sure the power parts are in their own region, the analog parts are in their own region and the digital parts are in there own area.
That means you probably don’t make a EMC test and don’t really care if it radiates?
When you are student, why can’t you share your project?
I apologize for not answering earlier
Well I’m in intership and that project belongs to the company I’m in. But as you suggested I will delete a lot then share the it. It will just look like the schematic sheets from the nucleo boards then
I don’t know what EMC stands for to begin with, so for now I guess no.
Do you mean located on the board?
First, you probably want to remove that zip file from filetransfer website quickly. It as some 10+ backed up versions of your project in the “backup” directories.
Next your schematic is a bit of a mess. In KiCad global labels (and power symbols are global labels too) are connected though the whole project. There is no reason (and it is confusing too) to use both hierarchical labels into a hierarchical sheet, and then use global power labels on those sheets too.
This whole project has the feel of a beginner with KiCad trying to do a first project that is too complicated. After a bit of browsing though all your sheets I found the part below:
If you delete that part and update the PCB, then you have both a GND and a AGND net.
But you should really figure out what you want to do with those “different” GND nets. Designing a proper GND distribution is an extremely important part of any PCB and just copying stuff from other projects without understanding how to handle GND is a recipe for disaster.
Thank you for letting me know, I deleted it.
Oh I didn’t know. Could you give me few advice then? What labels should I remove?
That is exactly what it is. In my intership, I’m learning the job of a pcb designer and it became a bit too complicated while I’m still a beginner.
Thank you ! You were right, power symbols are global labels. I thought it was exclusive to the sheet, like local labels.
I honestly don’t know 
I don’t understand the purpose of having different gnd and how to determine them. I just copy what seemed useful from my development boards to make my custom board
So 3 days ago I was right 
:
Electromagnetic Compatibility.
Devices offered at market must meet formal requirements in this regard.
Long time ago (2002…2004) I was searching in internet for articles about how to design PCBs in accordance with EMC and signal integrity needs. One articles serie I qualified as the best (in my opinion). That articles later became not accessible for some years and then later they were once more accessible. I hope links I gave 3 years ago are still valid:
In my opinion if you read these articles you will learn enough about PCB design as for your needs.
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Yes you were right
Thank you ! So maybe yes but it will not be my job to do this. My intership is about to develop code for the microcontrollor (which I finished) and now I have to make my own board. This EMC wasn’t mentionned to me.