Electronics Forum | Thu Sep 16 18:59:14 EDT 2004 | Carol
Thanks Everyone, the information was very useful. We use 7095 as a bible. A-610 6.5.3 doesn't allow for any solder balls not entrapped/attached etc. so we will look again at plugging/tenting both ends of the via. We ran into the problem of the mask
Electronics Forum | Tue Aug 11 19:46:34 EDT 2009 | padawanlinuxero
Guys I have a question since the ever present problem with the crack switch we had to change to a low temp lead free solder paste in these case eutectic 58Bi/42Sn and 57Bi/42Sn/1Ag alloys, now the main question whats diferent between these one and th
Electronics Forum | Thu Nov 14 21:53:04 EST 2019 | sssamw
I've seen crack on resistor also.The crack on ICs mainly is on the solder joint due to very high strain.
Electronics Forum | Mon Jul 26 21:25:19 EDT 2004 | KEN
I have seen as little gain as 2 months and even up to 6 months additional time to end-of life. Treat solder paste as a perishible item. Note DOM and Refridgeration life and expiration periods. You guys crack me up....now when ever I go to 7-11 I'l
Electronics Forum | Fri Jan 29 16:17:13 EST 2021 | donnie15
The impact is low on larger pitches and pad sizes. as things get to the .4mm pitch the pad differences start affect your ball size and yields. The trace size going into the pads and the solder mask relief can cause some odd shaped pads with signif
Electronics Forum | Thu Oct 26 11:49:54 EDT 2006 | sms_don
CW, The good news is that you are not trying to use SAC paste with SnPb balls for that would be a void generator due to the ball being liquidous while the SAC paste is still in a flux cleaning stage. Two points to consider: One, voids are not an i
Electronics Forum | Thu Aug 20 07:11:25 EDT 2020 | sssamw
What your said looks like a acrylic coating thermal expansion causes small solder joint crack. Do you cure coating with heating, or heating after curing? Solder joint crack while you see resistor and QFN trouble? Clear and detail description of your
Electronics Forum | Mon Nov 12 10:57:36 EST 2001 | emmanuel
We are to use a PBGA 272 and a PBGA 388. Between 500 and 750 thermal shocks (-45�C/+125�C), we have noticed that some cracks appear in the solder joints. According to our component specialists, these cracks are due to the whole design (pcb, component
Electronics Forum | Thu Jun 22 12:40:40 EDT 2000 | Boca
Everybody's right! Two concerns are proper preheat for the flux and reduced thermal shock to surface mount components. The stupid er dumb thing is that these can be at odds with each other. The flux vendor usually specs topside temp before wave.
Electronics Forum | Mon Feb 15 17:57:01 EST 1999 | Earl Moon
| Hope some of you out there can help me with this one. | I am getting feedback from our test department that they are showing opens on solder joints which have visually good wetting. The touch-up operators confirm that the joint looks good. All they
