Tag Archives: QFN

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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QFN Solder Paste Layer

Posted on February 2, 2012 by Duane

I’ve got the fab order placed with Sunstone.com for my next demo project. The little board is represented here at pretty close to actual size on screen – provided you have a 22″ monitor set at 1680 pixel horizontal resolution. … Continue reading →

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Picking Packages

Posted on April 8, 2011 by Duane

A long, long time ago, in a place pretty close to here, picking a form factor was easy. Your CPU came in a 40 pin DIP. Your logic came in 14 or 16 bit dips. You picked resistor sizes based … 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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AT Tiny is Tiny

Posted on November 16, 2010 by Duane

I just spotted a note on Twitter, from SiliconFarmer, referring to the ATtiny44A coming in a 0.45 mm pitch QFN as well as a 0.5mm pitch MLF package. (In practice, an MLF is the same as a QFN, by the … Continue reading →

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Scoopage

Posted on November 3, 2010 by Duane

I wrote recently about segmenting your solder paste stencils for the big open areas on your QFNs. The idea is that if the entire area is left open, it may end up with too much solder in the heat slug … Continue reading →

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Funky QFN Land Patterns

Posted on September 29, 2010 by Duane

I’ve described the optimal way to create your land and solder paste layer for QFNs a couple of times before. But that was for a standard square QFN or rectangular DFN. What happens if you look at the bottom of … Continue reading →

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10 Electronic Things to be Thankful For in 2009

Posted on December 2, 2009 by Duane

It’s that time of year when we take stock of what’s good in our little worlds. Since I’m writing this on my work blog, I’ll keep my top 10 items focused on work-related thingys. Number 10: Allocation!? Well, maybe. Nobody … Continue reading →

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Tented QFN/QFP Via-in-Pad

Posted on December 1, 2009 by Duane

Below is a pretty decent example of mask-tented vias in the thermal pad of a QFP. Most manufacturers recommend no more then 100 – 125 microns wider than the via to minimize voiding and thermal insulation in cases like this. … Continue reading →

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