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gamer87

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There is a problem in an electronic storage device that has electrolytic capacitors?
 

Not sure what you mean by "Electronic Storage Device".
Electrolytic capacitors degrade over time - especially at high temperatures.
 

capacitors electrolytic degrade many years are unused?
 

Sorry, I don't understand what you're asking.
 

gamer87 said:
capacitors electrolytic degrade many years are unused?
Click to expand...

The Electrolytic capacitors can and do fail over time; particularly if the circuit is unused for extended periods of time.

The capacitor works until the "leakage current" through the capacitor falls to an acceptable level. If an electrolytic capacitor is simply unused for an extended period of time, the dielectric will degrade; the longer it is not used, the worse the dielectric becomes. If the capacitance is reduced, the leakage rate increases. It will give enough power dissipation in the package to cause the electrolyte to boil, tearing the package forcefully.

The solution is replacing electrolytic capacitors with fresh ones and it is also a very common practice, and will help improve the reliability and performance of the circuit.
 

electrolytic capacitor unused for many years which presents problems?
 

gamer87 said:
electrolytic capacitor unused for many years which presents problems?
Click to expand...

I'm not understanding your question.

If your question is about the 'reason for the degradation', the answer I had mentioned in #5.

"the longer it is not used, the worse the dielectric becomes. If the capacitance is reduced, the leakage rate increases. It will give enough power dissipation in the package to cause the electrolyte to boil, tearing the package forcefully."
 

I understand your statement, you said electrolytic capacitor unused for many years lose capacitance and has high leakage current

capacitor SMD ceramic presents these same problems when many years unused stopped? capacitor SMD ceramic unused loses capacitance and gain high leakage current? capacitor SMD ceramic unused degrades?
 

Ceramic (and also Tantalum) capacitors should have a longer shelf life than caps with a electrolytic capacitors, because there is nothing inside to dry out.

The followings are also to be noted that in case of ceramic capacitor (in terms of aging).
Class 2 (X7R, Y5V & Z5U) ceramic capacitors, capacitance decreases over time, because of ferroelectric formulation. Failure also caused by other parameters like humidity content, temperature, etc.
 

I asked if capacitors ceramic SMD lose capacitance and have problems if they are many years stood unused?
 

gamer87 said:
I asked if capacitors ceramic SMD lose capacitance and have problems if they are many years stood unused?
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Reread jeevaaraam's post #9. They answered the question about ceramic SMDs in the second paragraph.
 

I did not understand well
 

jeevaaraam said:
capacitance decreases over time, because of ferroelectric formulation.
Failure also caused by other parameters like humidity content, temperature, etc.
Click to expand...

gamer87 said:
I did not understand well
Click to expand...

Seems clear to me that these are cited as the causes of failure.

Of course I'd have to research ferroelectric formation and perhaps learn the physics involved, but I imagine it's a problem involving formation of something that doesn't belong in a ceramic capacitor.

If you don't understand something start studying more about the subject. Repeating your question over and over isn't going to improve your reputation on this forum. It just makes you look to lazy to look up stuff.
 

I saw an article years ago telling how electrolytics have the chemical barrier become 'weak' after sitting unused a number of years. Full voltage should not be applied lest it destroy the capacitor. The author said the dielectric needs to be 're-formed', by admitting very small current until it charges to running voltage.

- - - Updated - - -

The risk might apply more to older electrolytics, rather than recently manufactured ones.
 

because electrolytic capacitors also fail if you do not use them for many years?
 

gamer87 said:
because electrolytic capacitors also fail if you do not use them for many years?
Click to expand...
I think that was answered by posts #2, #5, #7, and #14.

I think there might be a severe language barrier. You may need to improve your English if you want to understand the answers to your questions.
 

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