KiCad reference designators containing hash (#) (solved)

Sorry if this is a totally noob question. I have a couple of components in my schematic (LM22678 converters) which I’ve given the reference designator “U?”. When I generate a netlist, these get annotated to “#U018” and “#U019”. They don’t show up in the PCB layout.

I’ve tried googling this but it’s hard to know exactly what I’m looking for. What would cause the netlist generator / annotator to do this?

The DRC gives some errors on these devices, saying that a power input pin is not driven. Is that something to do with it? The pin is connected to a bridge rectifier and some capacitors - is there a way of fixing this without editing the rectifier part to make it a power output pin?

1 Like

These symbols have Define as power symbol option checked in Properties. This option should be checked only for power ports.

Use PWR_FLAG symbol.


Fantastic! Thank you!