KiCad: Pin connected to some others pins but no pin to drive it

I got sick of the limitations of the free version of Eagle and so decided to switch to KiCad. My impressions so far are that it’s an extremely capable tool, especially considering it’s free and without restrictions.

Anyway, this post is to point out the solution to a common and annoying problem. Any net in the schematic that has power attached must be explicitly specified as a power input through the use of a power flag. This includes anything like VCC, +5V, +VBATT, and GND. If you don’t you’ll get an error like this:

Pin connected to some other pins but no pin to drive it
@(...): Pin 1 (Power input) of component #PWR001 is not driven (Net 24)

In KiCad all nets must be driven, and while you’d think that connecting a net to a power input such as +5V would drive your net, it does not. Rather you have to explicitly drive the net with  a power flag. To get rid of the errors add a power flag for each net as follows:

Screen Shot 2016-03-12 at 4.31.49 pm
KiCad: Power flag on all power input nets.

Power flags can be added by pressing ‘P’ and finding the PWR_FLAG component.


3 thoughts on “KiCad: Pin connected to some others pins but no pin to drive it

  1. Thank you for short and clear explanation.
    I would add, there are other stupid things, like inability to parallel multiple power outputs, decouple a power pin with an inductor, or connect a power network to signal input of a volunteering opamp, etc. In all these cases KiCad throws an error. Therefore, generally, you need to edit every IC symbol, by changing AAALLLLLL the pins to “passive” mode. If you don’t do so, KiCad will stack like a donkey at the gateway and refuse to move further.
    Sometimes, imported symbols, like converted from Ultralibrarian, have “undefined” pins… again, you have to click every pin and “passivate” it.


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