While researching failure modes, I came across a number of articles on brittle fracture of ceramic capacitors that may be of interest to some. Sorry for the wrap.
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these-years
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tion/mlcc02/index.html
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lley.pdf
And if you can stand the nervous high-pitched squealing voice, EEVblog #1037 has some additional information. I only made it halfway through, but still got some interesting tidbits.
Lately we tend to panelize smallish boards. We generally route between the boards and leave little web thingies to hold them together.
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Some people here have suggested that v-scoring would allow more boards per panel. Sounds like snapping apart scored, stuffed boards could be a stress hazard to caps.
This thing slices scored boards apart, less stress than manual snapping.
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We don't seem to have problems with cracking ceramic caps. I wonder if some sizes are worse than others.
Most of our caps are bypasses, so if they open, we usually wouldn't notice. We would notice shorts.
Are you having troubles with cracked caps?
We don't use surface-mount film caps. They are really bad.
Digikey will save you time by selling pre-cracked caps:
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Gotta go: donuts are calling.
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John Larkin Highland Technology, Inc
lunatic fringe electronics
Another solution might be mounting tabs. From an article in Electronic Products,
"The most popular currently available surface-mount solution to this problem is the molded SMD package with formed metal tab leads that run down the side of the part and under it. These compliant terminations are free to flex back and forth with the board and effectively eliminate cracking or solder joint integrity problems."
SMD cap cracking isn't a problem for us, or for things like cell phones or car electronics. Exotic resistors with tabs will be hard to find and big and probably cost 50x a standard part.
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John Larkin Highland Technology, Inc
lunatic fringe electronics
I'm not worried about 0406 resistors or capacitors. it would be difficult to apply enough bend to crack them. I'm more concerned about MLCC, which is the main object of the links I provided.
Might as well watch the whole series. See Master Class diagnostics and troubleshooting at work. View cutting edge video techniques combined with exquisite narration. Drive yourself crazy with high-pitched nervous screaming, repetitive narration, glacial progress. Get it all here in one place:
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