π How to properly resolve Altium Designer ERC violations: errors, warning
Intro
Internal ERC (Electrical Rule Check) for the schematic could reveal small, but important mistakes, that help to fix design before board productionΒ πΌ
To get the most out of it, all components (symbols) should be created with correctly defined pin types (Input/Output/Open Drain/Power...) and connection matrix should be enabled end correctly configurated also.
β Strange thing, by by default settings unconnected pins in Altium Designer projects not marked as violation, so don't forget to fix it! |
Problem
If you use modern electronic components you might face with packages likes this (VSON, TFQFN, PSOIC, DFN):
In those and other packages several different pins could have the same internal connection and the same function. On the schematic it could be visualized in different ways, but the most properly way, when each pin of footprint represented on the symbol:
So, when connect two internally connected pins configured like Output and start ERC (Press: C, C and open View -> Panels -> Messages) the ECAD should show violation: warning or error.
To resolve situations like this some engineers just set this pins as passive, but it's incorrect, so now I'll show how easily deal with things like that using built-in instrument.
Solution
You can just place at this pointΒ No ERCΒ markerΒ and suppressall violation types,Β but by default settings it looks likeThin Cross and that confusing and can hook on to other important warnings. Moreover, Cross typically used to to designate only unconnected pins.
So if you place Cross No ERC marker and open Properties (Right-click -> Properties) you should change symbol to the Checkbox:
And then in Suppressed Violations section choose Specific Violations, when you can manually config suppressed Violation Types and Connection Matrix custom rules for this Checkbox:
So, to suppress previously reveled Output to Output pins connection I choose only one violation:
Try again Project -> Validate (Hotkey: C, C) and now only this specific violation successfullysuppressed
Conclusions
Don't ignore setting the right types of pins, because this can help to avoid design errors.
If you encounter misinterpretation of errors, don't turn off rules fully, use careful pinpoint suppression of a particular warning, because Altium Designer instruments make it possible without any problem.
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