Rounded Rectangle Pad Shape For SON & QFN
Printed From: PCB Libraries Forum
Category: PCB Footprint Expert
Forum Name: Questions & Answers
Forum Description: issues and technical support
URL: https://www.PCBLibraries.com/forum/forum_posts.asp?TID=617
Printed Date: 19 Nov 2024 at 9:52am
Topic: Rounded Rectangle Pad Shape For SON & QFN
Posted By: chads108
Subject: Rounded Rectangle Pad Shape For SON & QFN
Date Posted: 18 Oct 2012 at 1:05pm
| Is there a reason rounded rectangle pads are not an option for SON/QFN packages? |
Replies:
Posted By: Tom H
Date Posted: 23 Oct 2012 at 7:42pm
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There are only 2 SON/QFN component lead shapes - D-Shape & Rectangle However, that makes no difference to your question. We'll add Rounded Rectangle pad shape option to SON/QFN packages in an upcoming release (soon). |
Posted By: plinder
Date Posted: 14 Nov 2012 at 9:44am
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Is there a reason rounded rectangle pad shapes are also not available for SOD, TO, SOFL - or will those be added in the future as well? |
Posted By: Tom H
Date Posted: 14 Nov 2012 at 10:53am
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Rounded Rectangle pad shape will be available in every SMT component family except Grid Array packages. This is a new feature that is planned to be implemented this year. It includes QFN, SON, PQFN and PSON component families too. |
Posted By: DaveCowl
Date Posted: 14 Nov 2012 at 3:35pm
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Are people liking rounded rectangle for chip components (like 0402, etc.) or are they more of a leaded component thing?
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Posted By: Tom H
Date Posted: 14 Nov 2012 at 5:23pm
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I think that once you intruduce Rounded Rectangle pad shape for all Surface Mount patterns (except Grid Array) then that should improve fabrication, stencil paste application, assembly reflow and inspection. I believe Rounded Rectangle pad shape is the future for several reasons, but the top is "all stencil apertures are created using laser technology and that produces a corner radius on the SMT aperture openings. So why not make the pad shape match the stencil. Here are lead and lead free solder after reflow. There is no solder in the pad corners. Wouldn't it be best to shape the pad to the solder flow?
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Posted By: Tom H
Date Posted: 16 Nov 2012 at 2:28pm
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We added Rounded Rectangular pad shape to SOD and TO (DPAK) in V31 coming out this weekend. |