Looking for BIG capacitors.

[Scott Allen]

On Wed Jul 04,2007 02:19:07 PM Colin McGregor wrote:
> I am looking to clear an old electronic project that I
> started a while back and then never got finished. The
> problem was the design I was following calls for a
> 0.33 F  capacitor (yes, 0.33 F or a 330,000 uF cap.,
> which is HUGE). Fortunately the highest voltage this
> capacitor should have to take is 5 volts, so it
> doesn't have to be a very high voltage capacitor, just
> high capacitance.

Although huge in capitance, it need not be huge in size. I'm 
currently holding in my hand a 0.1F 5.5V capacitor. It is 1 
centimeter in diameter and 4 millimeters high. It was removed from an 
old VCR where it was used to provide power to retain program settings 
during power failures. A 0.33F one should be easily availble and only 
a little larger (well, maybe 3 times larger, but still small :-).

The problem with these so called "super-caps" is that they have a 
very high internal resistance, so they can't be discharged rapidly as 
could a normal cap.  However, they work well in their intended 
purpose as substitutes for rechargable batteries in certain 
situations.

As already mentioned, I would check out Digi-Key as a possible source.
<http://www.digikey.ca/>


-- 
** Scott Allen   scotta-cpI+UMyWUv9BDgjK7y7TUQ at public.gmane.org **
**     Toronto, Ontario, Canada     **
--
The Toronto Linux Users Group.      Meetings: http://gtalug.org/
TLUG requests: Linux topics, No HTML, wrap text below 80 columns
How to UNSUBSCRIBE: http://gtalug.org/wiki/Mailing_lists