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Ceramic capacitor will get damaged if repeatedly overvoltaged by spike?
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TimFox:
In my youth, I noticed that mica or paper capacitors in (relatively high voltage) vacuum-tube equipment often had two ratings:  working voltage and test voltage, where the latter was usually twice the former.  Obviously, the manufacturer did not recommend operation at the higher voltage, but thought it safe to operate at the lower voltage after they tested it at the higher voltage for a short time without failure. 
AndyC_772:

--- Quote from: Gyro on November 15, 2019, 08:22:09 pm ---Yes, MLCCs do blow. At low voltage, high current they will burn up and damage the board.

--- End quote ---
Agreed. I've seen a number of boards fail over the years with a short across the power supply rails, which turned out to be a failed decoupling capacitor. A thermal camera is often a good way to spot which one has died.

In my experience MLCCs are much more susceptible to mechanical damage during handling and soldering than they are to electrical stress. It's very easy to fracture one and cause the plates to short if you're careless.
BravoV:
I guess this is more a language problem thread, rather than tecnnilcal, as the OP doesn't fully understand the words mentioned in component's datasheet like -> "Rated voltage"  or "Absolute maximum rating".  :-//
Gyro:
For Electrolytics you will often find a time specified 'surge rating', probably dating back to the time taken for the valve heaters to warm up, but probably still relevant where the supply 'peaks' before something starts up.

Manufacturers 'Test' or 'Withstand' voltage is a one-time test under specific test conditions, you can't rely on it for normal operation.

As far as I'm aware, "Absolute maximum rating", only applies to semiconductors - and then only ICs. Other factors, such as SOA are much more important for discretes.

Operating above Rated voltage is a no-no as far as I was taught. De-rating is the order of the day for reliability. With MLCCs (in fact all caps) dissipation is also a critical factor. Thermal dissipation and eventual breakdown due to current waveforms is every bit as important. The OP didn't specify the capacitance value that he was pumping these voltage spikes into, and hence the current and thermal dissipation involved.
MagicSmoker:
KOA/Speer has a good document which goes into great detail on the very subject of this thread: http://www.koaspeer.com/pdfs/MLCC.pdf

From said document it is seen that Class 1 dielectrics (C0G, U2J, CH, etc.) will tolerate a way higher peak voltage than Class 2 or 3 dielectrics (X7R, Y5V). Figures 2-5 show the spread of DC breakdown voltage vs. initial voltage rating, and a 1nF/1206/50V C0G type will withstand nearly 6kV while an X7R version will crack (perhaps literally) at around 3.5kV*. The difference in breakdown voltage for AC is even more dramatic as the higher dissipation factor (ie - AC losses) of the Class 2/3 dielectrics add more self-heating to the mix from ESR. Finally, the pulse withstand capability is summarized in Figs. 17 and 18 where Class 1 dielectrics prove superior yet again.


* - These are "instantaneous failure" voltages, so not something the capacitors are expected to withstand. Still, you can reasonably conclude that brief excursions of a few % above rated voltage are unlikely to cause any damage whatsoever.

EDIT - added * comment.
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