Making Non-Identical Units Within a Part

Hello! I’d like to, using the Library Editor that I’m quite fond of, create a part with two units which are not identical. Namely, I’d like to draw a relay that has the coil as a separate unit from the switching. This allows the user to place the coil and switching wherever is most convenient, but export a single part in BOM and netlist.

Any ideas on how to accomplish this? Selecting two units when creating the part yields Unit A and Unit B which are identical. Tried the DeMorgan checkbox, though I don’t know what that is. Also tried checking “All units are not interchangeable” under component properties.

EDIT: In case it wasn’t clear, this is within EESchema, and I’m using BZR5228.

This would also be useful when placing IC’s with multiple parts. Right now power pins show up on every Unit, but if given a way to do the suggested, you could place power pins on a single Unit, but not show them on the rest of the associated Units.

Just tried it and it works for me. With all units are not interchangeable checked I can add pins of any type to separate units and they don’t show up on other units. I’m using BZR #5111 but I doubt this would be a regression, not much work on EESchema at the moment as far as I know. Drawings seem to come up as common to all units by default but right clicking and selecting “Edit line options” for example, gives an option to turn this off. There’s a “common to all units” option in the pin dialogue as well, have you got that turned off?

I’ve done this before to separate banks on large microcontrollers.

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There is also a button top right called edit pins per part. I found that useful. I use it for my opamps to separate the power pins from the signal pin body.

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You mean something like in this exported part? 74ls74.lib (994 Bytes)
I never use hidden pins on my non-power parts. I have the power pins on a last unit and put them all together with their bypass caps to make remembering which are the bypass caps (instead of filter or timing caps) 3 years later when l revew the schematic again. This trick I first saw in old Amiga schematics and like the idea enough to emulate it.

Faced a similar component… Rather frustrated until…

  1. In the Component editor, when creating component, set the desired number of units in Properties at the tab Options.
  2. Select “Part A” (aka unit 1) in the drop-down list.
  3. Draw all the graphics of the component in Part A.
  4. Time for the missing magic. Right click on an Arc that will remain only in Part A.
  5. Select “Edit Arc Options”
  6. Under “Sharing” remove the mark at “Share by all parts in component”.
  7. Click OK, now the selected Arc is only visible in Part A
  8. Repeat for all arcs, rectangles, polygons and text belonging to Part A. When it comes to text the option is found below “Text options:” “Common to Units”.
  9. Change the view to Part B. Select “Part B” (aka unit 2) in the drop-down list.
  10. Repeat the process for the things belonging to Part B.

For my component it was so much to define for each part that I opened the actual library-file (XXXX.lib), looked up the library files specifikation and altered it with a text editor.

Good luck


This definitely works.
Thanks a bunch SM4VLM

  • Desmond

This is a very old thread.
Having a variety of non-identical units is widely done now