Virtual schematic component

Schematic
1

Hi all,
as i continue working with KiCad a question came to my mind. What is the proper way to handle virtual schematic components. With virtual components I mean symbols like test points, screw holes etc. The reason why I’m asking is because I’m currently working on getting all my BOMs ready for production and I want to avoid that those virtual components appear in the BOM. For now I just gave them the prefix n.c. but It would be really handy to exclude those components from the BOM at all.

So my question: Is there a way already to exclude schematic symbols from the BOM or should this be a feature request? Or am I the only one that needs such a feature? :slight_smile:

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2

Already handled, in properties I think. There are three classes of components including these virtual parts

3

The virtual component option is handled in the footprint properties in pcbnew. I think it’s mainly intended for selecting which devices will provide positional information to the SMD placement machines. Since the BOM is usually generated from the schematic, this option probably doesn’t help with screening out virtual components.

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4

with the latest dev version of kicad, virtual can be used also for selecting mechanical models (i.e. enclosures) to be or not displayed on 3d viewer

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6

Andy is correct and I agree that creating the BOM in the PCBNew section seems not right. Coming back to my question as mentioned above I already changed the values of all those components to the prefix n.c. (not connected) but I was hoping that there is a more elegant solution for that.

The question is if it is worth making a feature request or just live with my quick solution :slight_smile:

7

Dave is correct, its pcbnew with the feature.
You can raise a feature request, but will have to wait for the rather drawn out schematic rewrite that is in progress.
The pcb part is much more recent and professional than the schematic application

8

Here’s how I handled a somewhat similar problem. It may give you ideas that apply to your own situation.

This schematic includes an antenna (2-element Yagi with a folded dipole driven element and integrated balun, for those who care) that is implemented with traces on the PCB:

780×607 5.35 KB

  • This is a “real” part

  • It has electrical connections

  • There is no component to purchase or install

I haven’t tried to use KiCAD to generate a formal Parts List or BOM. I use an Excel spreadsheet to create P/L’s and BOM’s. The entry for the antenna is (click on the image to make it legible):

1644×154 11.1 KB

Dale

p.s. - And if you’re interested, the antenna is a footprint, with copper layers that look like this:

1295×831 3.69 KB

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Some may want screws to be included, so they do not get overlooked… :slight_smile:
For testpoints, you could use the same Value tag as assembly variants, like a DNF (Do not Fit), then the BOM that skips DNF option parts, also skips test points

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This gets into the realm of “configuration control”, and can quickly degenerate into arguments that are both pointless and endless.

  • The screw (plus nut, and washer) that secures, say, a connector or a TO-220 power device to your board will probably appear on the Parts List (P/L) for the PCB Assembly . . .

  • . . . Unless those thru-hole parts are installed in a separate operation from the SMT components on the rest of the board, in which case the mounting hardware may appear on a separate P/L that includes the components added later

  • The screw (nut and washer) that secures the PCB Assembly to the chassis or enclosure may appear on the P/L for the PCB Assembly, or on the P/L for the Chassis Assembly.

The “correct” approach is usually dictated by the habits, customs, and inertia by the local organization for whom you are preparing the P/L. If the guy (or gal) in configuration control says you did it wrong, you smile, say “Thank you.”, and change it.

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