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  3. Variable trace width during serpentine routing for PCIe...

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Variable trace width during serpentine routing for PCIe 5.0 (PCB Editor 23.1)

bengelJF
bengelJF 8 hours ago

Our electrical team was discussing the recommendation below from Texas Instrument's app note "High-Speed Layout for PCIe Gen 5":

It's easy enough to change the width of a given cline segment by hand, but ideally this would happen automatically during delay tuning so we don't have to do this by hand (takes more time, easy to miss a segment). Additionally, we run into the "snowman problem" when just changing trace widths, where the larger segment doesn't blend nicely into the smaller segment:

So, our question is this: In PCB Editor 23.1, is it possible to set up trace widths to adjust automatically to match TI's suggestion in their app note, and if so, is it further possible to get nice blended transitions from thinner to wider segments?

Thanks all!

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  • DavidJHutchins
    0 DavidJHutchins 7 hours ago

    I developed some skill code for this issue years ago, the solution for the 'snowman' issue was to split the 45' segment as the location of the width change, as show below:

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