How to label a pin as active low?

How can I label a pin on a part, and on the PCB, as active low using the convention of a bar above the text?

Unless someone can suggest a parts editor method, I’d expect you need to make a custom part and use Inkscape (or another svg editor) to add the bar. Its easy once you know how but learning how takes a bit of time. Do you have an example of a part you want done?


Can’t you just pull a label out of the bin and make a line and put it there as a work around, or do you want a permanent fix.

A permanent feature would be much better - something like a checkbox to indicate the signal is active low and automatically changing the font of that pin (or label etc) to include the top bar.

If the quick answer is ‘no, the software does not support this feature at this time’, I’ll understand. I was hoping I had just missed a setting somewhere or there was an easy trick to doing it.

TBH I’m not going to spend a lot of time learning how to modify SVG files, so perhaps the easiest workaround is to simply add an apostrophe (or prime marker) to the end of the text like this: OE’ or R/W’ as an alternative to indicating active low I learnt in my youth.

Thanks for the suggestions.

I realize this is an old topic but since it comes up in Google searches and there actually is a proper solution, I’ll add it here.

You can put an “overline” on top of any character by following it with Unicode character ‘COMBINING OVERLINE’ (U+0305). The overline will merge with the character. To do this with a whole word, insert the overline after each character in the word.

eg. RESET becomes R̅E̅S̅E̅T̅

This works everywhere you would want it to — unfortunately, the official “Droid Sans” font doesn’t render it very well. It’s an imperfect but practical solution.

Alternately, Unicode character ‘COMBINING MACRON’ (U+0304) can also be used. It works in very much the same way but may not combine with multiple characters as well. I also don’t think it is as semantically correct.

Hope that helps someone.

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