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unexpected DRCs after changing mechanical pads of USB-C connector

Manfred1

I am refering to the USB-C connector JAE DX07S016JA1. It's symbol contains a non-plated hole and slot. presumably for improving mechanical ruggedness.

The symbol is drawn with imperial units, but our pcb manufacturer uses metric drills, which are avaiable in 50µm steps of diameter.

So I made a backup copy of the symbol (the .dra-file) from within the file-explorer. Then I opened it, identified the pad-files of the hole and the slot. I opened both pad-files, adjusted and changed them to metric units and saved them with a different name, refering to the metric units.

In the symbol, I replaced the hole and slot (pins) with the newly created pads and saved the .dra-file with the same name as before.

In the layout I chose "Placement edit" as application mode, selected the USB-C connector's symbol and in the context menu chose "Quick utilities" / "Refresh symbol".
But now a lot of new DRC errors emerged, even several Pad Soldermask to Pad Soldermask Spacing errors between pads that I did not even touch!

I tried to find out about possible reasons for new DRC errors in the documentation "Help" / "Documentation" burger menu "Allegro PCB Editor" / "Allegro User Guide" / "Creating Design Rules", but did not suceed.

Can you guide me into the right direction?

  • Andrew Beckett
    0

    Note from a moderator (I don't cover this specific forum but approved this post): The reason this got flagged as potential spam (it's clearly not spam) is because it contains external URLs. Historically we have had a lot of spam on the forums which just clone a post and add a link to some external dubious site - and rather than annoying everyone in the user community with lots of spam posts (which happened in the past), there end up being a relatively small number of posts that do have to go through an approval process to ensure that we keep our users free of bad posts which are very hard to detect otherwise. My apology for the inconvenience. I'll see if we can get the wording changed on how it is reported back to you.

    Andrew

  • steve
    0

    The Refresh Symbol command would automatically run the Update DRC's command so maybe you hadn't run that and DRC's were there all along or some new DRC checks were enabled. You may find if you have changed units from mils to mm you may see "rounding" errors unless you have allowed enough decimal places to make the changes, Check the values of what you have versus what the DRC is reporting which may help you decipher what's happened. 

  • Manfred1
    0 in reply to steve

    Thank you for your reply.
    No, the DRC check was up-to-date. I issued an "Update" - command with the old version of the USB connector. I did not enable new DRC checks intentionally. Are there possibilities to enable new DRC checks unintentionally, such as by simply exchanging or refreshing a symbol?

  • steve
    0 in reply to Manfred1

    Not really - what happens if you run the Update DRC before you make the change to the connector? That may help. Also check which version you are actually running from Help - About. It should be 22.1 S002, 17.4 S035 or 17.2 S083. If it not the latest as listed, download and install the latest version from Download Manager or support.cadence.com and see if updating the software helps. 

  • Manfred1
    0 in reply to steve

    The version shown at Help / About is 17.4-20019 S017.

    Updating seems to be impossible, because my reference key has expired.

    If I update the DRC before changing the connector, no DRC error pops up.

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