Electronics Forum | Tue Jun 24 12:56:26 EDT 2014 | jmathis
Hello, As our company has begun doing an increase production of contract manufacturing I have seen more and more designs with the 0402 pad layouts that are smaller (.015 in width) than the component. Also there is only a .008 longer than the 0402 p
Electronics Forum | Tue Jun 06 17:20:05 EDT 2000 | Travis Slaughter
There is no difference in 0402�s on the bottom side than 0603 0805 1206. They will not fall off or tombstone, unless they where before you put them in the oven.
Electronics Forum | Tue Feb 04 17:24:07 EST 2003 | jonfox
we have some pretty tight 0402 placements and our best fix was to reduce the pad (vertically speaking) from .030x.022 to .020x.022. Fewer tombstones and the paste flows out to the edge of the pads nicely. Only difference is that we have a 6mil sten
Electronics Forum | Thu Aug 07 01:23:43 EDT 2003 | craigj
Does anyone out there have any info on track balance ratios. i.e. heavy track entering 1 end of component (0402) and thinner track leaving other end and how this effects/causes problems like tombstoning. Am trying to put together design rules for cus
Electronics Forum | Thu Feb 24 12:08:13 EST 2000 | JAX
Mark, This topic has been discussed multiple time on this site. You can find almost all of them by searching the archives for tombstoning. That aside, have you look at your stencil apetures?(homeplate design).
Electronics Forum | Thu Feb 24 12:08:13 EST 2000 | JAX
Mark, This topic has been discussed multiple time on this site. You can find almost all of them by searching the archives for tombstoning. That aside, have you look at your stencil apetures?(homeplate design).
Electronics Forum | Thu Jun 02 17:24:19 EDT 2005 | PWH
Could also be a ground plane under one of the terminations of the cap causing heat sink troubles during reflow. One pad liquifies/solidifies before the other. Don't know a good solution for this outside of reworking them.
Electronics Forum | Tue Jun 14 17:25:29 EDT 2005 | peter ng
the pcb pad design problem?(the component able to fully located at the pad?).....or maybe the component(cap)problem?try to exchanged the part and reverse the pcb direction of the reflow entering.
Electronics Forum | Tue Jun 21 08:03:32 EDT 2005 | mapell
Curious... are you running any N2 in your reflow? If so what ppm level? I have worked with some reflow users that low ppm levels (
Electronics Forum | Sat Apr 14 04:33:44 EDT 2007 | aj
the footprint is IPC standard which I have found to be less forgiving than the Jedec one for tombstoning. Enig finish - 5 thou stencil. We have historically used homeplate design but I am leaning towards 1:1. Leadfree application. aj...
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