Electronics Forum | Thu Apr 11 14:31:15 EDT 2002 | aaelect
We're having some problems with 0402's tombstoning. On a board with about 300 parts we're getting about 12 to 20 tombstones per board. The caps seem to do it more often than the res. The pads appear to be in accordance with IPC SM 782 amendment 1, S
Electronics Forum | Thu Apr 11 20:35:22 EDT 2002 | davef
Messy. Messy. Messy. Consider gluing these components, until you control your process. It is unclear to us that a single factor drives these defects, but multiple factors that need to be tuned to work well together. PAD DIMENSIONS * Some SM-782 pa
Electronics Forum | Thu May 24 16:45:57 EDT 2001 | kmorris
Hi All: We�ve got a problem here with opens on bottom side wave soldered SOT23s. Based on past experience and review of the SMTnet archives, I feel that our main problem is pad size. We have the same size pads for bottom side SOT23s as we have for
Electronics Forum | Tue Dec 26 11:26:00 EST 2000 | acahill
If you have a known problem with the parts, then Reject them back to the Vendor. It appears that you have a solderability issue. As for Tombstoning on 0402 chips, this could trace back to the stencil design and/or machine placement. Define Tombstoni
Electronics Forum | Thu Jun 02 14:50:41 EDT 2005 | techknow..
Placement looks good...paste to pad coverage good..correct profile used and verified by tracker. The problem being that this one cap is tombstoning at the same place every time. The placement is central. The part is near the edge at the break off.
Electronics Forum | Tue Jun 14 18:37:18 EDT 2005 | GS
On top to above suggestions,Round pad designe (where possible to get) helps to solve tombstoning pbm. Regards GS
Electronics Forum | Mon Apr 16 09:13:16 EDT 2007 | pjc
Tombstone head and a graveyard mind. I would not recommend 1:1 due to solderpaste beed out opportunities. Have you tried the inverted home-plate? Here are some good links on tombstoning and how to eliminate it: http://www.aimsolder.com/technical_ar
Electronics Forum | Fri Aug 08 12:52:57 EDT 2003 | davef
So, if you give your customers design guidelines and one their products causes a cataclysmic explosion, resulting in the deaths and disfigurement of many handicaped third-world children, could a lawyer consider you responsible? Spec Fir Tree General
Electronics Forum | Thu Jun 02 15:56:42 EDT 2005 | jimmygam
run the board thru both backward and sideways and see what happens
Electronics Forum | Fri Jun 24 15:37:24 EDT 2005 | KT
Also check for any Vian-in-pad designs that could cause the problem.
.png)
