Unable to connect traces to pins PCBNew

Layout
1

Hello KiCad community,

I am wrapping up my first board in PCBNew (I’m a Mechanical Engineer and usually don’t do the PCB design…long story) – I have the physical layout all done and 95% of the traces routed. I am having difficulty getting several traces to connect to the pins of my last IC. The rats nest does connect the pins, but when I route a trace from the component to the pin of the IC, it blocks me out in the same way it would if I were trying to connect to a pin that was not connected in the schematic. I cannot originate the trace from the pin either – it selects the pin an highlights the other components/traces it should be connected to, but when I move the cursor away from the pin, there is no trace. When routing from any other component, the trace does show and the rats nest line turns yellow and guides me to the pin, but then blocks me out.

The footprint I custom made for a TPS61200 boost voltage regulator (QFN 10 package)

I’ve been banging my head against the screen for 3 hours now with no progress. Any help/suggestions are greatly appreciated!

2

If you run a DRC check on that, what does it say ?
Most likely is trace size/pin pitch/rules combining to not allow a legal path.
Also possible, is a bad footprint design that has some internal violation.
You could add another part, with the same pad-pitch, and see of you can route to that ok ?

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I went through the footprint design many times and found nothing out of the ordinary.

The QFN 10 is a tiny package, so after checking the design rules, I found that the clearance was set to 0.254…taking that down to 0.2 solved the issue. Thanks for pointing me in the right direction!

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