Tag Archives: land patterns

More Beagle CAD Paws

Posted on December 10, 2012 by Duane

Continuing on from my last post … As I said, I do everything I can to avoid reusing the package footprint when adding the the parts library in Eagle CAD. The schematic symbol can be a different story though. It … Continue reading →

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Beagle CAD Paw Prints

Posted on December 4, 2012 by Duane

Unfortunately, I can’t generically hand out Eagle CAD QFN footprints without knowing the specific part, but I can illustrate the areas I initially had difficulty with. All of the traps that used to get me seem blindingly obvious now, but … Continue reading →

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An Unanswered Question

Posted on March 11, 2011 by Duane

I’ve been reading through my Virtual PCB chat session transcript from Tuesday. It was a fun session and I have a much better idea of how the virtual shows work now. I think I may just be getting it. The … Continue reading →

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Rework Foibles

Posted on January 25, 2011 by Duane

Yesterday, I wrote about my foibles in ignoring my own advice. As SiliconFarmer pointed out over on Twitter, it’s not just something you need to do when you’re re-purposing a close land pattern. Sometimes even the “correct” pattern can have … Continue reading →

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Lesson Learned … or Not

Posted on January 24, 2011 by Duane

I’ve written quite a number of times about the perils of CAD software land patterns. Especially if you don’t have an exact match and need to adapt something close. Recently, I was looking in my Eagle library for a low-drop … Continue reading →

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On Final For Landing on Runway 0805

Posted on December 16, 2010 by Duane

Keep out areas can be a problem when adapting a CAD component land pattern, but that’s not the only potential problem. Sometimes the part may be close, but the footprint is different enough to cause problems, as in the picture … Continue reading →

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Monsters Under the Bed

Posted on December 1, 2010 by Duane

Monsters, metaphorically speaking, that is. Take a look at this little land pattern for a TO-263 part. Can you tell me the two main things wrong with this land pattern? I’ll give you a hint. One of the problems is … Continue reading →

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0.4mm Pitch BGA Land Patterns

Posted on November 29, 2010 by Duane

We’ve been getting more questions about laying out the 0.4mm pitch Ti OMAP BGA, as is used in the Beagleboard. As I’ve written before, some of the rules change at these tiny geometries. The Beagleboard folks discovered that non soldermask … Continue reading →

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Land Patterns – Equal and Not Equal

Posted on November 19, 2010 by Duane

I was recently asked a question about QFN package varieties. The questioner wanted to know if different package variants of 16 contact QFN packages, such as HUQFN, DHVQFN, SQFN and such, all shared the same footprint. If they did, the … Continue reading →

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Extra-Fine Pitch BGA Pads

Posted on June 24, 2010 by Duane

One of the annoyances of the world of trade secrets and proprietariness is that we can’t all learn from each others’ experiences. That is important, and even generally necessary, in a competitive world. If you put in some hard work, … Continue reading →

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