Electronics Forum | Thu Feb 02 09:07:28 EST 2023 | charles_nguyen
Two types of land patterns used for surface mount pads are non-solder mask defined or NSMD pads and solder mask defined or SMD pads.Each type has its own advantages and disadvantages. There is a statement that SMD pad type may introduce stress concen
Electronics Forum | Wed Feb 08 09:43:08 EST 2023 | charles_nguyen
Thank you for the above information but what I want to talk about is the PCB design aspect. Should there be any warning about it in the DFM?
Electronics Forum | Thu Feb 02 10:10:20 EST 2023 | tommy_magyar
Perhaps google this, as you will find very interesting articles. For scientific explanation look up solder fatigue on Wikipedia with references added. A more in depth explanation you can find on the Digikey forum where you will find other people like
Electronics Forum | Fri Feb 17 19:23:05 EST 2023 | SMTA-64387083
Read the articles everyone else recommend. I haven't read of them but I will say this. A Solder Mask Defined pad is a copper flood that has much more thermal mass than a Non-Solder Mask Defined pad so it will heat and cool at a slower rate. I suspect
Electronics Forum | Fri Oct 29 02:07:48 EDT 1999 | Eom In Soub
hi. guys Have you out there ever seen the crack by means of humidity after reflow solering. We cannot analyze the cause of the tsop crack. The shape of crack seem to be hitted by sharp stuff. but there is no scar around crack . TSOP shaped long rec
Electronics Forum | Wed May 22 10:27:42 EDT 2019 | Matt
thanks again for the feedback were your cracks mostly visible in relation to images shown in the document here: https://www.digikey.ca/en/pdf/t/tdk/guide-flex-cracking-mlcc most of our cracking has been lengthwise across the body which from what i
Electronics Forum | Wed Jun 13 21:31:27 EDT 2001 | davef
Lotsa ways to bust caps. First: placement force; Second: thermal stress; Third: poor pad design. Forth: then, ummm maybe the cap supplier. Please describe the crack in more detail. Where does the crack start? Where does the crack go?
Electronics Forum | Fri Apr 18 16:53:25 EDT 2003 | takfire
DST, What was the crack signature? Was the crack parallel with the internal electrodes or 45� with the terminal electrode? It is also important to determine the orientation of the failed caps on the PCB (in regards to depaneling). Perhaps the cap
Electronics Forum | Thu Nov 13 09:14:52 EST 2008 | raiders
Hi All, We encounter capacitor crack in the ICT, it contributes 2% of the failure. We are not sure whether these crack coming from the SMT. All these crack having the same pattern. Please refer to attached file. Anybody encounter the same thing befo
Electronics Forum | Wed Sep 27 12:44:52 EDT 2000 | Ashok Dhawan
What could be possible resons for " Plating Crack on Barrel (tented via)" This tented via is in proximity to parts being hand soldered. The crack in barrel was detected on failure analysis - micro-section of via where barrel is having crack ( circul
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