Hello, I need help with the PCB layout. I don’t understand the error message “Annular with(board setup constraints min annular width 0.1mm; actual 0.05mm)”. Although I have tried different values in the Design Rules (see markings in the enclosed PDF) the error remains. If needed I can upload the project. I am happy to pay for help. I using 7.0.9
Thank you Jakob
DRC_problem2.pdf (311.8 KB)
Annular Width is the distance between the side of a hole, and the outside edge of a copper pad. It is important because the location of the drilled holes always has some tolerance and the complete hole has to be within the copper area even when the location of the hole shifts a bit.
For the rest, your screenshot is not very helpful. The error message is for a via, while you are showing a pad. The probable solution is to either make the via’s bigger, or the hole in the via’s smaller.
The minimum via diameter seems very low at 0,2mm when considering the 0,1mm requirement for the annular width. Via diameter is exactly twice the annular width, in other words there is no space left for a hole. I don’t remember from the top of my head what the smallest manufacturable conventional (drilled, not microvia) via hole diameter is, but say it is 0,2mm. Then you have a minimum annular width of 0,1mm, so your minimum via diameter becomes 0,2+0,1+0,1mm = 0,4mm. Check with your manufacturer what they can produce at a price point you are comfortable with, and insert the numbers.
Thank you for your responses. If I change the via minimum diameters, the number of error messages do not change, just the values reported by the DRC. Probably my workflow is wrong. Is it correct just changing the diameters in the constraints and run DRC again? Or do I need to go a step more backward. I looked into examples of the demo files. I see there via values which are in the range you recommend. DRC runs in those examples without errors. I have to say, it is my first time I build a board with this complexity (Arduino nano with about 30 components) Jakob (could I post the project?)
This is your minimum annular width:
To make DRC happy, you need to:
Make your annular widths on your footprints/vias/whatever larger than .1mm
or Change your minimum annular width in the Board Setup to under what you are using (0.05).
After completing your changes you then need to re-run DRC.
Board Setup is found under File.
The DRC errors indicate that you have already placed vias with 0,05mm annular ring. These do not change when you change the minimum values in Board Setup → Constraints. You will need to manually replace these vias with larger ones if you want to keep the annular ring width minimum at 0,1mm. They do not get automatically modified or replaced.
1 Like
Thanks Henrik,
I didn’t think of that required action when I wrote above. I just assumed, silly me 
Thank you all for your input. It helped me to understand the dependencies. Jakob
1 Like
The constraints shown above are just average numbers filled in to make it easy to get started. They are much the same as the line thicknesses and colors and hotkeys and everything else for that matter.
They are there to alter as you wish or require. 
This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.