Electronics Forum | Sun Jan 14 16:35:48 EST 2007 | Austin
I have several boards built at various CM's. We have prototype builds with some JTAG failures on BGA's (1-3 failures with qty 3, 1500 pin BGA's). CM's always claim reflow profiles look good. X-ray does not show bridges and they claim it looks good, b
Electronics Forum | Fri Feb 09 11:48:09 EST 2007 | realchunks
0.25mm tilt? That's pretty small depending on you BGA size. Is it failing? Or just your Q.E. being anal? What size BGA we talking about? What ball count? Just one board? Maybe cheaper to just repair. Now assuming there is NO part under the BGA
Electronics Forum | Wed Sep 25 06:56:16 EDT 2002 | CH
U may check your profile ramp rate. The flux may evporated and look like cold joint
Electronics Forum | Mon Mar 01 10:27:08 EST 2010 | wrongway
I don't think I would reduce the heat at all if there is no vibration in your oven or on the chain you should have no problem with them falling off or moving but you sure don't want a cold solder joint you no the solder joints are so easy to see go
Electronics Forum | Fri Apr 26 05:50:54 EDT 2019 | ppcbs
We just apply tacky flux to the surrounding components and to the bottom side components under the BGA. This will prevent cold solder if any solder joints reach reflow temperature the surface tension will keep them aligned and in place. If you nee
Electronics Forum | Tue Mar 20 05:26:32 EDT 2007 | CL
Hi Chrissie, BGA Rework from one CM's view: 10% process problem (printing, reflow, voids, etc) 10% component failure (no other problem found) 80% "The board does not work therefore it must be the BGA" This, of course, is exaggerated. My point bein
Electronics Forum | Fri Apr 10 13:25:21 EDT 1998 | Jon Medernach
| Is there a good way to inspect BGA | balls ? Is there an inspection piece | of equiip.? The idea is to develope a process that eliminates insoection. BGA's, by the nature of the design, do not lend themselves to inspection. Even X ray is subjec
Electronics Forum | Fri Nov 09 19:31:43 EST 2007 | yshiau
Thank you to Dave and Scott!! What I'm delaing with is mass production test for small memory cards in volume! The reason I choose Non-operating temperature cycling is so that I can deal with volume. I can throw in quite a few memory cards in chambe
Electronics Forum | Tue Nov 06 07:34:26 EST 2007 | scottp
I'm not sure what kind of marginal joint you're trying to identify, but when we went through a serious ball-in-cup problem a few years ago we tried hot & cold functional test as well as a day or two of -40/+125C thermal cycling and all were pretty po
Electronics Forum | Thu Jun 19 10:47:29 EDT 2003 | Eric QE
Caltex or Ersa type system is good, Caltex prisms, necessary for looking underneath the BGA can be crashed easily when looking under low profile or Micros. $40-$110 each depending on the availability and who makes 'em. We have 2D and 3D X-ray avai
