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Laying out PCB traces between pins


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As you may notice near the center of the image I passed the outputs from the far side of the chip between two pins. Increasing the trace thickness as the traces were originally drawn caused some DRC (Design Rule Checker) issues. I replaced the trace between the pins with sections to let me increase the size of specific parts of the trace leaving notches where the traces pass by the pins. Am I askng for trouble? For higher power applications, would it be better to suggest to those wishing to,  to scrape off the solder mask over those lines and add solder to give higher current handling capacity? Am I making much ado about nothing with respect to the target audience of this board?

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How wide is the trace as it goes between pins?  How much current ( I don't see what you are referring to in the pic) does it need to handle?  How long is the narrow section.  Generally, when you "neck down" to go between pins, it will still be about 15 mils wide and only for about 200 mils or so at most.  That can still handle about half an amp to an amp in that section.  The pcb design book I linked a while back has a LOT of information on that sort of thing.

The trace width between the pins is 26 mils, and, the length of the thinnest section is 40 to 50 mils (one is longer than the other).

Based on your current handling comment, it would seem expanding the traces is probably overkill. I have room and it doesn't seem to be harming anything. I suppose I will keep it as is.

How did you manage a 26 mil trace between pins?  DIP spacing is 100 mils, and an IC pad is normally 70 mils ( sometimes 60 ) So with a 26 mil trace that only leaves 4 or 14 mils for spacing, or 2 or 7 on each side.  The 2 is not workable, and the 7 is really pushing it.  Most board houses can't do less than 8 and that is pushing their abilities.  A 25 mil trace in 1 oz copper can usually handle an amp or so for a farily long run.  A 20 mil trace between pins only wouldn't cause any problems for up to about an amp, I think.

I wouldn't even have thought of this. Good catch!