[solved] Sheet label and hierarchical labels

Hello everyone,

I was trying to perform a rule check to see if my design was valid and noticed a few errors concerning the hierarchical structure.

Vin is the external Power which supplies the regulator: Hierarchical label VIN is not connected to a sheet label

I was not able to find what a sheet label is. VI on the regulator is an Input, so is my hierarchical label VIN. The same problem is with +5V and some other hierarchical labels.

Do I have to declare additional information when I want to connect these pins from the outside?

You connect a global label to the hierarchical label on the inside of the sheet. Making the hierarchical label redundant (no need to define a connectable interface for something that is already connected)
What did you try to achieve here?

Generally if you mix global labels in with hierarchical design then you remove much of the power of this design methodology. See Hierarchical or flat schematic design, what is best for me? (How to deal with multi page schematics?)

For the VIN it makes sense. The +5V is going outside the hierarchical structure and is also needed inside (for other parts)

I don’t quite understand why you don’t just use the global label at the other end of the +5V hierarchical pin. (Either that or get rid of both the global +5V and R14_IN globals and connect the other ends of them via the hierarchical structure instead.)

Mixing these label types only creates confusion (case in point: your question) Especially when done on the same net. (It would be ok of you have the 5V hierarchical pin and then connect your global labels in the sheet instantiating your currently shown subsheet.)

Additionally: Are you aware that a net can not have both the name of +5V and R14_IN? one of them will win. (Undefined behavior as both have the same priority. Assume kicad chooses one of these two possible names at random -> If you intend to use a zone in pcb new then this will create problems as a netlist update could change the netname without you having changed anything obviously impacting this)

Also: What do you understand under “sheet label” (in the title). Maybe you have a misconception of what the global labels do.

These symbols appear to have been selected by their similar appearance in a different design software.

I am in agreement with the OP that the graphical symbols can be easily misunderstood at first glance if familiar with certain industries with perhaps not the same standards as Made in China products that end up being sold at McDonalds.

I am a bit confused about your response.

Yes there are packages that have (only) point to point references but i have never seen them in a pcb design tool. (Closest is eagles “XREF” modification of global labels that however kind of breaks if you use that label at more than two places.)

I have seen point to point labels (or references in that case) in tools like eplan where you really need to define where the wire goes to. Additional requirement then is do not use normal junctions but directional ones that define on which end of a junction two wires connect (looks a bit like a skewed Y or a K with one of the diagonals missing). This is done as the connection wires are made by a machine to the correct length with the end points automatically labeled. (Manufacturing is cheaper if the software or the designer already define both end points of every wire instead of simply saying “this connector is connected to ground”.)

This is not a requirement in the pcb world (i mean you could make a pcb tool like that but i doubt people will be happy if they need to go back to the schematic everytime they rearange two resistors in the layout.)

@Rene: R14_in and +5V was a mistake. thank you

I did not realize that the global label is also connected to the hierarchical label. I thought global means specific for the sheet.

I will redesign my hierarchical sheet to conform with the correct design rules.

Thanks for the help

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