Electronics Forum | Sun Jun 30 20:00:56 EDT 2002 | redmary
the SOIC encounter solder crack after reliability test, the common process is: SMT---manual soldering---IPT(in process test)---potting---T/C(thermal cycling,only add current and voltage)---B/T and F/T (burn in and functional test). the condition is 2
Electronics Forum | Mon Jul 01 15:37:56 EDT 2002 | pjc
Possible cause can be design related- if the solder land is too small. Check w/ IPC SM-782 Solder Land Design Guide Another is board finish. I have seen problems like this with Gold finished PWBs- which creates a more brittle solder joint.Another pos
Electronics Forum | Mon Jul 01 20:42:54 EDT 2002 | davef
Comments [questions] are: * It�s strange that an uggie ol� SOIC, 50 pitch, BIG honkin� solder pad, kinda thang is failing. Sumpin aint kosher, yano? * Where is the failure occurring [ie, lead to pad, pad to board, etc]? Talk about the breadth and di
Electronics Forum | Wed Feb 20 23:17:34 EST 2002 | surachai
I AM JUST EVALUATION LEAD FREE EVALUATION AND FOUND THE BIG PROBLEM OF SOLDER CRACK BETWEEN TERMINAL OF COMPONENT AND THE INTERMETALLIC LAYER OF LEAD FREE ALLOY BUT DON'T FIND ANY CRACK BETWEEN SOLDER AND SURFACE OF PCB , COULD YOU HELP ME VERIFY T
Electronics Forum | Fri Feb 22 15:16:24 EST 2002 | rkevin
Bet your using tin/ lead plated components with a lead free Cu/Ag/Sn alloy. It leads to intermetallic cracking. Wow didn't anyone tell you to check the archives yet, It seems to be the answer given to everyone. Why have an interactive site if you alw
Electronics Forum | Tue May 25 07:03:34 EDT 1999 | Milan Z.
After reflow proces in convection-IR oven we find broken body of SOT23 elements. There is no problems on other elements (SOIC, chip R,chip C, etc) Where is the problem? Thanks in advance!
Electronics Forum | Wed May 26 18:04:16 EDT 1999 | John Thorup
| After reflow proces in convection-IR oven we find broken body of SOT23 elements. There is no problems on other elements (SOIC, chip R,chip C, etc) | Where is the problem? | | Thanks in advance! | Check your profile at the site of cracked component
Electronics Forum | Mon Aug 01 06:59:02 EDT 2005 | Joseph
Dear all, We observed visible micro crack at top side of solder fillet during lead free wave solder process. We did not see any visible micro crack at bottom side, and it always located at joints of transformer. Any input be much appreciated. Best
Electronics Forum | Wed Aug 10 10:41:23 EDT 2005 | patrickbruneel
Bob, Great theory if you're selling SN100C, but I have to disagree that an alloy being 4�C off eutectic will cause cracks. When a solder joint exits the solder wave, there is an immediate drop in temperature of 100�C. so being off 4�C is irrelevant.
Electronics Forum | Mon Aug 01 09:06:33 EDT 2005 | davef
Based on your description, it sounds like the solder connection is defective. Further description of board and solder materials and assembly processes would be helpful in moving forward.
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