CD4093

[stoica adrian]

Hi,

I am designing a circuit around CD 4093.

I have the following difficulty: I do not find the power pins for this component, can anyone please let me know how to activate this pins?

As you can see on my screenshot, there is no ''Unit E'' allocated with the power pins for this component.


Thank you,

[Karel]

To me this looks like an error in the library.

The powerpins are hidden. They are called "Vdd" and "Vss".

[Kleinstein]

It could be an old entry in the library using hidden pins with defined GND / VCC names. 
Under the Enschema settings (display options) one can enable showing the hidden pins.

The hidden pins are an old feature that in my opinion causes more trouble than it is good for (it works with the logic chips if they all get the same supply, but already some extra filtering for some chips can cause nasty problems). AFAIK (and I would totally vote for it) this feature is discuraged and should be removed, but some old parts may still have it. I learned the hard way with some 74HC1G04 or similar.
So an upgrade/fix of the library would be a good idea - though maybe not technically an error but only an old entry.

[Benta]

I'm running 6.0.8 and I see the power pins. It's the two small circles. You don't see then in the Symbol Editor overview.

[julian1]

In kicad 6 at least, there is hef4093b quad nand. It has a extra unit E, with power supply pins represented, rather than being hidden.

If the naming is a bother, copy it into your own library, and use a text editor to rename.

[Doctorandus_P]

Hiding the power pins is a remnant from 40 years ago. Back then it was quite common. PCB's with logic IC's tended to be pretty big (100+ IC's was no exception) and all of those IC's were connected to the same power supply. In these modern times, with Logic IC's most often used as some glue logic, with different power supply voltages on the same PCB and EMC regulations it does not make much sens anymore to hide the power pins.

So you can use the symbol from the: "4xxx" library, which has the power pins as "Unit E", or you can just use some net labels on your power supply to name them appropriately. If you: Schematic Editor / View / Show Hidden Pins then you see the Vss and Vdd names of the hidden power pins.