Questions and musings on workflow

[Narmondur]

I just got into LibreIPC literal days ago, and fiddling with it has resulted in some questioning on the proper workflow. I’d like to hear from the more experienced users wether my current understanding is correct, and correct it where it isn’t.

My initial understanding regarding custom libraries was that personal custom libraries were to be created on a project-by-project basis, but further thinking on the subject brought me to the conclusion that this would be incredibly irritating, as you’d end up having to redo the basic components like resistors, diodes, inductors and capacitors again and again for each project. Having come to that conclusion, I then posited the idea to myself that a local library would be more of an ever expanding virtual box of parts: You start from nothing, create parts as you need them, and eventually you end up with a variety of parts to pick and choose from. Is this correct?

Regarding creation of parts: Is it always a must to follow the pipe “create component category” → “create symbol” → “create component” → “create Package category” → “create package” → “create device” → “create part”? I ask because at least with my workflow I end up making the schematic first with no regard to what the actual PCB might look like and which specific components to use. As such, I don’t often even know what package or part I am going to use. Is there a method in which I can finish my schematic and then go, “okay, these resistors map to these parts I just dug up, these diodes map to those parts.” Do I always have to work from component category up to schematic symbol if I want to leave the PCB design 'till later? For now I’ve just used generic symbols from the core libraries.

Finally, is there a way to have sheets be disconnected from any given net? My way of using sheets in the schematic editor is such that the main sheet has a block diagram of the whole project, and the further sheets detail each block in turn. Given this, I might end up using same labels across sheets and I might not want them to connect together. Is this just the matter of using unique labels on each sheet?

Just to illustrate this point, in my project there will be a controller circuit driven by an arduino, which connects to a raspberry pi with USB and is powered by a battery with its own charging circuit. I could very well imagine that both the charging circuit and controller circuit might have the label “voltage in”, but with the arduino circuit it means either battery or external power supply, and in the case of the charging circuit, that label would mean just the power supply.

I don’t know if I made any sense with that… feel free to ask questions, and thank you for anyone who has patience enough to try and provide me with answers.

[ubruhin]

Hi,

@Narmondur

Having come to that conclusion, I then posited the idea to myself that a local library would be more of an ever expanding virtual box of parts: You start from nothing, create parts as you need them, and eventually you end up with a variety of parts to pick and choose from. Is this correct?

Yes this is exactly correct!

@Narmondur

Regarding creation of parts: Is it always a must to follow the pipe “create component category” → “create symbol” → “create component” → “create Package category” → “create package” → “create device” → “create part”?

Hm yeah you have to follow this order of part creation, but you don’t need to do all at once. It’s fine to just create up to the component and finish your schematic with these components. Then you can create packages/devices/parts later when starting with the board design. The device needs to be chosen latest when adding a component to the board, but choosing a part is not possible during the placement process. So currently you need to choose the part in the properties dialog of components in the schematic editor (or in the board editor).

@Narmondur

Finally, is there a way to have sheets be disconnected from any given net? My way of using sheets in the schematic editor is such that the main sheet has a block diagram of the whole project, and the further sheets detail each block in turn.

I’m not sure if I understand correctly what you want to do. But for a “pure graphical” (non-electrical) sheet, I’d recommend to use the drawing tools “Draw Polygon” and “Add Text” as these do not add any net. And you should not add “real” components to those sheets as they will appear in the board editor (although you can just ignore them, but it’s a bit ugly).

[Narmondur]

Hm yeah you have to follow this order of part creation, but you don’t need to do all at once. It’s fine to just create up to the component and finish your schematic with these components. Then you can create packages/devices/parts later when starting with the board design. The device needs to be chosen latest when adding a component to the board, but choosing a part is not possible during the placement process. So currently you need to choose the part in the properties dialog of components in the schematic editor (or in the board editor).

does this also stand on very basic components? What if I want to have a resistor while not really having an idea what kind specifically? Resistors are already a component category and there’s already a lot of basic info defined, it feels silly to me to duplicate all of that, so how do I proceed in this case?

Thank you, I will use the drawing tools and add text tool to make my overview page

[ubruhin]

@Narmondur

Hm yeah you have to follow this order of part creation, but you don’t need to do all at once. It’s fine to just create up to the component and finish your schematic with these components. Then you can create packages/devices/parts later when starting with the board design. The device needs to be chosen latest when adding a component to the board, but choosing a part is not possible during the placement process. So currently you need to choose the part in the properties dialog of components in the schematic editor (or in the board editor).

does this also stand on very basic components? What if I want to have a resistor while not really having an idea what kind specifically? Resistors are already a component category and there’s already a lot of basic info defined, it feels silly to me to duplicate all of that, so how do I proceed in this case?

I’m not sure if I understand your question fully. But generally if you want to add a resistor to the schematic, just pick the already existing resistor component. No need to duplicate anything. And no need to create any package/device/part in the library yet. Then later during board design, choose the desired device, either an existing one or a new one by creating a package+device.

Maybe it helps to watch our recently created video tutorials on youtube. A board design tutorial will be added soon.

LibrePCB

[dbrgn]

Maybe one aspect wasn’t clear: Your library doesn’t need to be self-contained. You can reference parts of other libraries (e.g. symbols or components from the LibrePCB_Base library that you downloaded through the library manager).