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DRC Troubles. Same net spacing. Thermal connects

Delf13

Hello everyone!


I got stuck with two troubles in Allegro PCB.

Look at the figure. The line between SMD and Throu hole pad was made manually. DRC show an error, because the clearance between the line and the copper pour less than 20 mil. I don't know how to convince the Allegro to increase this clearance. Of course, I can do it manually by adding Voids. But I reckon if Allegro pours a copper automatically, it have to follow its rules automatically also.

The second 'bug" you can see below. Allegro made the thermal connection and broke his clearance rules. And it didn't show violation! I got the question from manufacturing company about clearances!

Is that "bug" of Allegro? Or I did something wrong?

  • steve
    The issue is because you have routed a cline of the same net throough the plane (It's not using the thermal relief connection here). You need to use Edit - Properties then select the cline segment and add a property void_same_net to that cline, then update the DRC's and the DRC should clear.
  • Boma

    Ivan,

    Try changing your Global Dynamic Shape Parameters under Void controls Minimum aperture for gap width to 10.00.  Also,for thermal relief connects use a minimum of 1 for Smd pins and vias so not to loose connectivity.  Re-smooth your shapes and update DRC and both problems are gone.  Good luck.

    Boma

  • Delf13
    Thanks for answer! It really solved the clearance issue. But I can't figure out why Allegro didn't see a clearance violation between thermal connection and a line (the bottom of my picture).
  • steve
    There is no DRC because it's using the Line-Line Spacing rule which is currently set to 12 mils. FYI use Display - Constraint then window the two clines to see the ruleset that is being used
  • Delf13

    Steve,

    I attached the incorrect file. I hurried to resolved the problem and correct errors in other way.

    When I wrote message I tried to reproduce the bug and didn't noticed that bug was disappeared. :(

    For now, I can't reproduce it. There were Air gap about 10.5 mils, but the rules were 12 mils.

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