Author Topic: Interactive Differential Pair Routing Not Adding Vias  (Read 1253 times)

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Offline hal9001Topic starter

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Interactive Differential Pair Routing Not Adding Vias
« on: April 15, 2021, 12:00:00 pm »
Im using the interactive differential pair routing tool. Whilst routing when I switch layers, I expect 2 vias to show and space according to the rules like when using  the regular interactive routing tool, but vias are not showing up when switching to any layer. There aren't other traces or components near by.

Did I change an option by mistake? Has any body seen this before?
 

Offline hal9001Topic starter

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Re: Interactive Differential Pair Routing Not Adding Vias
« Reply #1 on: April 15, 2021, 12:05:33 pm »
The differential nets names end in _N and _P and contain differential directives on the nets in the schematic.
 

Offline T3sl4co1l

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Re: Interactive Differential Pair Routing Not Adding Vias
« Reply #2 on: April 15, 2021, 04:32:22 pm »
Right, the nets must be named and classed correctly otherwise you can't use P, I at all.

Also, the rules are consistent between layers, right?  Obviously, you can't route pairs on layers they're prohibited on...

Interactive routing is weird, sometimes you can hit L and it just places vias wherever (at current follow/look-ahead position, or last solid traces), sometimes it whines and gives you nothing, in which case you have to undo the L (hit it a few more times) and press 2 instead to lay down some vias.  And then you might still not be able to switch layers and have to cancel, select the vias and resume from the desired layer.

Is that what's happening, or have you been through that and it's still not working?

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 
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Offline hal9001Topic starter

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Re: Interactive Differential Pair Routing Not Adding Vias
« Reply #3 on: April 15, 2021, 08:15:18 pm »
L did not make any vias so I hit 2 and that finally added the vias but had to switch layers as you said. Weird behavior indeed  |O, wonder why 2 is the only method that works.

Saved me hours of trial and error, many thanks Tim!
 

Offline T3sl4co1l

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Re: Interactive Differential Pair Routing Not Adding Vias
« Reply #4 on: April 15, 2021, 10:25:18 pm »
I think it depends on what you started routing from, or something?  It feels weird and inconsistent, so I never stopped to take note of what is actually doing it, and just stop and re-route like that. :shrug:

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 


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