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Resiliance of ceramic caps to overvoltage?

eem2am

Aug 3, 2009
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How resilient are X7R ceramic capacitors to short term overvoltages.

In other words, say i have a 16V, X7R, 22uF sepic capacitor, and every time i switch on the sepic, i get a 20V spike across the 16V ceramic for about 30us......is that going to be ok?

How long will such a capacitor last.?
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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It's worth checking the specs for the capacitor for the "dielectric withstanding voltage".

In this case they specify 250% of the rated voltage for 5+/-1 seconds, so 30us is fine.

However, whilst I wouldn't take this figure as a general one, the significant difference in both % overvoltage and duration suggests that you (and more importantly, your capacitor) will be fine.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Another drawback not often mentioned is their extremely brittle nature.

edit: that's mentioned on page 2 :)
 
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