SMD JEDEC Designations

TomS

I would greatly appreciate if someone from Parallax would please give me the JEDEC designations for the two
Propeller SMD chips. I want to make absolutely sure I have the proper pad
layout before I have boards made. I think it would be a good idea for Parallax
to provide a recommended pad layout on your website for all of your SMD chips.

Thanks
Tom

Phil Pilgrim (PhiPi)

The info you need has been posted here: http://forums.parallax.com/showthread.php?p=598127

-Phil

TomS

Thanks Phil,

I need the QFN also. When do you think it will be posted?

Do they have JEDEC designations? I can generate the patterns if I have JEDEC desg.



Thanks

Tom

Phil Pilgrim (PhiPi)

Tom,

The QFN land pattern is the first one posted in the thread I gave you.

-Phil

Tracy Allen

I've never found a JEDEC designation for that package. QFNs are relatively new territory, I guess. On the QFN package, be sure to note that the solder paste layer is a little different from pads layer. The paste on the center pad is divided into 4 sections that cover 50% of the pad area.

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Tracy Allen
www.emesystems.com

Paul Baker

Tracy is correct, the center ground pad should be 50% covered with paste by design of the stencil. 100% coverage "floats" the part during reflow and there is greater likelyhood of non-contact of the pins to thier pad.

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Paul Baker
Propeller Applications Engineer

Parallax, Inc.

TomS

I meant the QFP pachage.



Thanks

Tom

Phil Pilgrim (PhiPi)

Tom,

The QFP is also in the same thread. Just scroll down a little...

-Phil