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Changing Line Width of a Trace in a Net without DRC Errors

TC2019

Hi,

I would like to know a way to change the line width of a trace within a larger net without DRC errors.

I have a net with 100mil line width assigned to it. There are several traces branching off from this main 100mil line that I want only 8mil thick (e.g. pull-up resistors/decoupling caps). When I manually change the line width for these traces (and they are long traces), I get millions of L><W error markers on them. Is there a proper way to do this in OrCAD PCB Designer Standard 17.2 version (and I am new to it).

Any help would be greatly appreciated. Thanks.

TC

  • in reply to TC2019

    You will need to force an update to the DRC checker any time you change constraints on existing routing or placement.  When you rip up and re-route the dynamic checker (which needs to be on) will re-run as soon as you route.  There is an icon typically at the top of the screen that is the DRC check button and the command is buried in one of the menus as well.

  • in reply to excellon1

    Hi Excellon1,

    What you said is a very good practice. In this design, I have a few BLMxx ferrite beads for EMI and net separation. I also use nano PTC fuses for protection. It's similar idea but was not really intended for the routing purpose (didn't see these errors coming).

    Over the last few days, I moved things around a bit and used many copper polygons to enclose those high-current nets. The Neck Mode routing together with longer neck length as you suggested did the job. The board is now fully routed without error. I need to learn how to post process it as my next task. I am pretty sure I will need help on this.

    Thanks for your help again.

    TC

  • in reply to redwire

    Hi Redwire,

    I see DRC Update icon on the top left, not sure if it is the same one you talked about. Unfortunately, every time I click on it, the software simply closes/crashes. I am not so sure what it is causing it. It also does the same when I click on Update DRC button in the window after Check - Design Status.

    I am new to this OrCAD PCB, still learning but so far I cannot really say it is the most user friendly or efficient software. It sure needs a lot of mouse clicking, too many really for a single task. It seems like I have clicked over a few millions Oops and Done doing this board.

    TC

  • in reply to TC2019

    Hi,

    maybe you are using"product" software without patch ? It can explain crashes; "base" software without update are generaly not stable.

    Help->about: return

    17.2-2016 S059

    with actual updates

  • in reply to TC2019

    Hmmm...correct button.  Crash should not be happening.  As JC Tess mentions, check your release.  The other thing that occasionally can happen is a corruption to the pcb database.  Run the tool called database doctor (standalone) or Tools->Database Check which will scan the database for some incorrect entries.  Personally, I just don't see a crash on this so something sounds whacked.

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