I am using KiCad V7.0.7 in a Win64 laptop. In my PCB layout, I have differential clocks. I am able to tune the length of these pairs very well. There are some caveats with trace length reporting between what is displayed in the tune tool, the message panel and the Net Inspector. I understand these differences and can get my pairs to a desired length.
My issue is with tuning the skew. I have ~14 mil of skew between the pairs and would like to reduce this somewhere between 5-10 mils. Using the 9 hotkey, I can select either pair, open the skew tune window and modify my skew distance (the default is 0). All of this is fine until I want to select my shorter trace and add to it. The tool will report this as the longer trace and will not add the small “bumps” to increases the length. Instead, the skew tuner calls the longer trace the shorter and will allow me to add the allotted skew to it. This makes my skew even larger. I am guessing this is a bug and am wondering if others have encountered this.
Others have used it. During the 7.0.x cycle I see a few bug fixes in length tuning.
You can submit your project confidentially on the issue tracker for the developers to have a look
I truly appreciate everybody’s replies. I’d like to first see if this is operator error. What dsa-t and craftyjon have said got me thinking. Specifically the “thin yellow line”. Below is a pic of my diff clock line. You can see that the yellow line stops on both P and N nets in different spots. Is this related to what craftyjon has said about extra track segments? Should I see the yellow line along the entire track length (via to via)?
Thanks craftyjon. I’ve been fixing track segments where the yellow line stops and can see the yellow line continue after that. That was a huge help. When I fix both pairs, I’ll report back on how the skew tune works.
Thanks all for your help!! It was operator error. After fixing my diff pairs and confirming the yellow line went from pad to pad, I was able to use the skew tune tool successfully.
