HIdden pins (upper and lower case) problem

Hi there
I am having some problem with the hidden power pins. The 74132 libray has hidden power pins named Gnd and Vcc (lower case). They are not connect to power nets named GND and VCC (upper case). So, how can I fix it? Is there any way do place power ports named Vcc and Gnd? Please advice.
BR
Gilberto

You can edit the symbol to make them the same. What version of Kicad are you using? The librarians put in a lot of effort to standardize these.

I’m using a fairly recent Test Build, with (As Far As I Know) with the current libraries.

I thought these issues with the 7400 series library issues were fixed some time ago. However, doing a KiCad search for the 74132 part ( and a few others ) the pins were labeled “Vcc” and “Gnd” while the common “Power Symbols” were “VCC” and “GND”.

@Gilberto_Ermacovitch what I would recommend would depend upon how many 74000 series parts you will use in your design.

If it is just one or two, at the moment, then I would modify the symbol into a custom library.

If using many 74000 parts, then I would suggest to modify the power symbol with the same case as the current library.

Maybe, the easiest way is to hover the mouse over the VCC power symbol and depress “Ctrl+e” on the keyboard. Then right click the symbol on the left hand pane and select “duplicate” from the drop down menu. Change the name to mixed upper and lower case and save.

At the moment I don’t know what the KLC recommends, nor if it might change in the future.

S4.6 “Hidden power pins are also not allowed.”

See discussion here:

A list of these problematic parts, either in the issue linked above, or as a new issue, might help library work forward. It might be possible to find problems using a script that search for hidden pins with certain names also…

I would suggest to modify the symbol in any case. Hidden power pins are just too dangerous.

We don’t allow hidden power pins for a long time now. We simply do not have the manpower to fix everything.

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NOT to Pic-Nit, but I find the hidden GND pins to declutter the schematic on IC’s. The idea of hidden pins was originated with purpose in mind, but sometimes the original intent gets lost in the forest.

So long as the option for hidden pins remains for my own libraries there will be no complaints by me. It seems like many really REALLY like the great big green dots all over the schematic. I like that the schematic be uncluttered by things I do not need to see.

Have you considered going into testing to see if you would be a suitable candidate for cloning? Then perhaps your clone could consider being the next candidate for cloning!

Knowledgeable manpower after two test sessions!

Invisible power pins are only usable in a very limited case where you only have one power supply on a board. And even there you might want to communicate which decoupling cap belongs to which IC.

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No problem with that but the librarians picked a standard based on conversations on this forum. Personal choice. I bit myself with my own symbol that way though. It was like having a screen with a dead pixel. That invisible connector was keeping me from doing something. I don’t remember what. It’s documented here somewhere though.

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Invisible power pins could also wreak havoc on a design that maintains two or more isolated “grounds”.

It’s great to have a tool with features and flexibility, that can be adapted to many different workflows, personal preferences and styles, and local practices. Keeping all of the pins visible is a kind of “lowest common denominator” practice, well-suited to casual and inexperienced users but also acceptable to many well-seasoned and quite advanced users. I have no objection if a subset of the user community decides to expend the time, effort, and resources to create and maintain a parallel library featuring hidden pins and devoid of “connection dots”.

Dale

Please don’t mix the two, though.

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Some of my recommendations are based upon my actual real-life experiences with schematics. I’ve had to troubleshoot boards with 150+ 7400 series logic chips; all powered by one supply. The extra 300+ schematic markings on the schematic would just be unnecessary visual clutter.

Again, I’m NOT against providing the feature to those that want to see all those extra markings, but I don’t want them forced onto my KiCad schematics. The hidden pin concept was coded for good reason in my opinion, and I don’t understand how some keyboard warriors want to force everything to be visible onto every KiCad user.

Not everyone has a 60in large format plotter to put their designs onto paper. In fact, I have found that reasonably scaled schematic drawings are well managed when printed onto a 17x11" paper size. At the moment I only have an 8x10" printer and reducing the visual clutter and print space is important to me at this moment in time.

So have I, but that was 30 years ago and I don’t expect to design a new board dominated by discrete logic again.

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Not to the same extent, but that is exactly what I am doing with another design concept; and I also did not expect it.

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