Electronics Forum | Mon Sep 06 04:42:18 EDT 2004 | KenF
Thx for the replies. Acutally I am doing a process related study to see whether the process (pcb depanelling)can induce crack to an MLCC. After depanelling, I will do a thermal shock on the MLCC based on IEC 384-1, that is, five cycles of 30min at hi
Electronics Forum | Fri Sep 03 11:28:18 EDT 2004 | KenF
Fine crack in multi-layer ceramic capacitor (MLCC) may not be detectable by capacitance check.Could anyone out there advise which is the most appropriate method to test/detect fine crack ?
Electronics Forum | Fri Sep 03 16:47:40 EDT 2004 | davef
Rob's comments make sense. Responding to your question: * Sometimes you can see a resistance change * Sometimes you can see a leakage change
Electronics Forum | Fri Sep 03 11:45:15 EDT 2004 | rlackey
Hi Ken, I know this doesn't help in the immediate timescale, but isn't avoidance the best form? can you trace the cracking to a process issue (Solder profile, shock damage, handling damage, probe/ATE damage)or a chip cap manufacturing fault? I can'
Electronics Forum | Thu Sep 09 04:51:19 EDT 2004 | Simon UK
65%), if one failed on the board i replaced all of them, and re-tested and thermally cycled them inline with our spec (-55/+80 Deg/C for 48hrs) this was a nightmare, especially when some cracks were not detected until several weeks later while flying
Electronics Forum | Thu Nov 13 11:45:04 EST 2008 | pbarton
We have seen a similar problem. Turned out to be mechanical stress on the component caused by the method of location and clamping at ICT. Where is the component located on the assembly? Poorly adjusted clamping pillars on clamshell fixtures can cause
Electronics Forum | Thu Aug 15 16:45:09 EDT 2019 | stephendo
I just found this. https://www.avx.com/docs/techinfo/CeramicCapacitors/cracks.pdf It is extremely dated but still interesting. From the conclusion; " but both thermal shock and overstress cracks propagate at angles near 45°. Defective components h
Electronics Forum | Tue Sep 10 01:56:53 EDT 2019 | itrueriko
I got solution to manufacturer to find out the crack of MLCC if the manufacturer need it.
Electronics Forum | Thu Aug 15 09:36:48 EDT 2019 | davef
It could be delamination of the layered material of the MLCC caused by thermal shock or a component fabrication defect. For more on MLCC cracks: https://www.avx.com/docs/techinfo/CeramicCapacitors/cracks.pdf
Electronics Forum | Wed Aug 14 18:17:32 EDT 2019 | slthomas
We are down to the last few unresolved PCBA test failures in a work order and scrambling to get them repaired and into a mechanical assembly. What we have found in quite a few of these cases are cracked 1206 MLCCs. The failed parts are all the same
