ERC Errors with NC jumpers


#1

Regarding ERC
I have the power input coming into a reg as shown running through a Normally Closed Jumper.
I intend to open this jumper and use it to measure current draw before the reg during the first round of PCB prototyping - then remove the jumper all together before final PCB production.

I do this quite a bit for current measurements or to give myself a nice spot to add additional resistance or capacitance etc around my circuit so that I’m not soldering on and off SMT parts to fine tune the board.

But it fills my schematic with ERC errors. In the example shown, the power coming into the jumper (JP102) from a larger 80 to 5v switchmode supply and it’s correctly marked as a power output so it must be that the jumper is not appearing closed. (Tested if I short the jumper with external wire no ERC ERROR)
How do I make this part closed without having to draw a shorting wire on it and have to remember not to route it later?
I’m in the habit currently of ignoring ERC errors but its bitten once or twice and I need a cleaner solution.
Any Ideas?


#2

OK seems like an easy fix is to add another power flag after the jumper :wink:
But in other cases where I like to have a 2.54 female header to say insert a pto resistor or cap - these are still a problem.


#3

I believe the canonical solution in KiCad is to add power flags where needed, or to create custom symbols which have a pin with power out. If you use current shunts regularly, that might be a cleaner solution.

Tbh, I’ve never found the “no pin to drive it” error that useful, it creates too many false positives, and it’s easy to incorrectly add a power flag. It’s still essential to have “check power connections” as a checklist item for human review.


#4

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