Electronics Forum | Thu Aug 05 09:21:45 EDT 2010 | doug_johnson
I am havein a lot of trouble with KINGBRIGHT LEDs tombstoning in the reflow oven. It is a PLCC2 package. The stencil apatures are home plated. Can anyone help me
Electronics Forum | Tue Apr 22 02:27:38 EDT 2008 | fowlerchang
Many factors will make tombstone happen. from design/stencil aperture/soler paste/placement/reflow and so on. here is one article about tombstone which I prepared long ago. send me your email if you need it.
Electronics Forum | Fri Sep 09 11:01:14 EDT 2005 | rob
If the tombstoning is thermal (occuring during reflow) then try slightly reducing the stencil apertures so there is less the paste on the pads, reducing the forces acting on the component. Also take a look at the cooldown profile & making it more
Electronics Forum | Wed May 31 13:14:42 EDT 2000 | Dason C
I learn from Senju Metal, they have a formula with certain percent of Ag and Cu can elimate the tombstone. The hint is the eutectic only one reflow and the new material have two reflow. Please let me know your result. Rgds. Dason
Electronics Forum | Thu Mar 13 15:22:47 EST 2003 | ruggi
Ditto on the profile/reflow oven...a couple years ago, we had a huge increase in the number of tombstones found post-reflow. Profiling the oven showed a decent curve with some innocuous minor deviations, and further investigation of the oven found 2
Electronics Forum | Tue Feb 23 16:05:46 EST 1999 | Randy Haller
| What to look for that causes tombstoning and the corective action. | 1:check reflow profile 2:reduce pad size 3:reduce deposition of paste(stencil thickness/opening of aperatures) 4:Check components for solderability Good Luck
Electronics Forum | Sat Aug 12 02:52:16 EDT 2017 | tsvetan
There is no solution in above case, this is caused by the PCB design. There are no thermals on the pads connected to the copper poured area. So the other pad reflow first and lift the component.
Electronics Forum | Sat Jun 10 07:27:24 EDT 2006 | davef
Chuckie: SM4007A Diode case is D0-214AC G. Eisner: On tombstoning: * Check reflow profile * Pads per IPC-SM-782 * Reduce amount of solder paste * Check component solderability * Place component accurately * Search the fine SMTnet Archives for backgr
Electronics Forum | Thu Aug 06 12:16:52 EDT 1998 | Rin
| I'm currently running a double sided paste smt board loaded with 0603's, on the secondary side. Many of the 0603 devices tombstone during reflow if the parts are not perfectly centered on the pads. Is this caused by the .008 foil thickness? Has any
Electronics Forum | Tue Aug 24 15:15:43 EDT 1999 | John Thorup
| Could use a little help here. Can anyone clarify to me the cause and fix of chip caps/resistors tombstoning following reflow? | | Any help would be appreciated. Thanks. | Most common reason is uneven heating where one side of the component ach
