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Author Topic: Capacitors  (Read 486 times)
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Can you damage a capacitor by switching a circuit from the ground rail? Like using the Adriano to trigger a N-Channel Fet to then power circuits that I pretty sure pull more than 50ma. So these circuits would be connected directly to the V+ rail, and switched from the V-.
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Left Coast, CA (USA)
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A capacitor will most commonly be damaged under the following conditions.

1. If it's a electrolytic capacitor and you apply reverse polarity voltage.
2. If you exceed the manufactures maximum rated voltage of the capacitor.
3. Exceeding it's maximum or minimum rated environmental operating temperature.

Other possible causes of damage:
Placing it in a fire.
Driving over it with your car.
Pounding a nail through it.

If you have a question about a specific capacitor in a specific circuit you should probably post a schematic drawing so we can try and figure out what you are asking about.

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Ha ha ha ha...Thanx. I didn't think it was a problem. I was reading about not properly connecting one to ground can damage it, so it got me wondering...
I am REALLY a Newbie to all this stuff. Leaning tons over the last few months though.
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Manchester (England England)
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Also if you exceed the ripple current rating a capacitor can explode.
When it happen to a colleague in my lab the whole room was filled with fluttering silver foil, it was like it was snowing.
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You missed the most common and important reason for damaging a capacitor.

Don't vacuum them up off the floor.
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That depends... because I am "advanced" in age my vision isn't what it once was... and a "No Bag" vacuum cleaner is my friend when I drop a part into the carpet... I've pulled 8 pin TSSOP packages from the folds of the filter in the 'cannister' a time or two.
On the Main topic...\
As Mike pointed out the current flow through an electrolytic must be accounted for as well as the operating voltage AND temperature as electrolytics change value at the extremes of temperature which is a good reason if any at all for using twice the value you think you will need and you Always Need Good Bypassing for proper operation of your design.

Bob
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