Tune track length issues on differential pairs
Bug #1428290 reported by
Nick Østergaard
This bug affects 1 person
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| KiCad |
Fix Released
|
Medium
|
Tomasz Wlostowski | ||
Bug Description
Using rev 5475.
Steps to reproduce:
1. Make a differential pari
2. Tune the length of the one track
3. Tune the length of the other track of the same pair is in 2. (It may matter to make sure that they are not of equal lenght)
4. Use the tune differential pair lenght tool on that pair
Expected result:
it would in a sensible way override the tuning doine by the individual tunings
Result observed:
Some of the track from the previously made meanders become straight lines, that does not in any sensible way seem to be impedance matched anymore. See the attached screenshot. A pcb to test on is attached.
Also some other wierdness where the tracks will be invisible occours on attemps to tune after the above steps.
Revision history for this message
| Nick Østergaard (nickoe) wrote | #1 |
Revision history for this message
| Nick Østergaard (nickoe) wrote | #2 |
| Changed in kicad: | |
| assignee: | nobody → Tomasz Wlostowski (twlostow) |
| Changed in kicad: | |
| importance: | Undecided → Medium |
| status: | New → Confirmed |
Revision history for this message
| Tomasz Wlostowski (twlostow) wrote | #3 |
| Changed in kicad: | |
| status: | Confirmed → Fix Committed |
| Changed in kicad: | |
| status: | Fix Committed → Fix Released |
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Hi Nick,
The straight line and invisibility problems have been fixed some time ago. We can't do tune overriding for the moment - it needs a file format modification to store info which segment belongs to which diff pair. For the same reason, we don't have yet DP gap constraints (just a single width/gap). I'll fix it when the stable is out.
Tom