Hi,
	First off, think I wasn't very clear in my post, but my motors
run off the unregulated side of the power supply. The regulated side is
for digital circuitry and such.

	Right now what I'm gathering is that the tant prolly isn't up to
the task of regulating the battery supply. Instead I probably could
consider a solid aluminium electrolyte. However I think that for the 5V
regulated side a 16V tant should do the job pretty well.

	Thoughts anyone?

------------------------------------------------------------------------
Daniel Chia

"Genius is one percent inspiration and ninety-nine percent
perspiration."

     - Thomas Edison

E-mail: danielcjh@yahoo.com.sg
MSN: danstryder01@yahoo.com.sg
ICQ: 37878331
------------------------------------------------------------------------


> -----Original Message-----
> From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On
Behalf Of
> Russell McMahon
> Sent: 05 September 2005 04:33
> To: Microcontroller discussion list - Public.
> Subject: Re: [EE]: Tantalums cap for power supply regulation
> 
> > Generally, tantalums are most *un* suitable for power supply
> > applications.
> > They are quite prone to failure, sometimes in spectacular fashion. A
> > low-Z aluminum is a much safer bet.
> >
> > If you *must* use them, then heavily derate the voltage (use a
> > capacitor
> > rated for 3 times as high as the working voltage), and follow all
> > data
> > book recommendations to the letter.
> 
> Yes. This is a warning which must be noted. Tantalum capacitors are
> superb when they work. They offer very high capacitance per size and
> excellent ESR. But in an amateur or experimental situation where
> conditions are not well behaved or well known they can fail
> catastrophically.
> 
> A tantalum cap that experiences a voltage spike higher than its rated
> voltage, even a very brief one, will often fail very spectacularly.
> They often smell bad, make interesting sounds, smoke, catch fire or
> explode in various combinations. I've seen  one do all of these in
> that order :-).
> 
> Manufacturers spec sheets often specify minimum supply impedances they
> should be used with and even suggest adding some ohms of resistance in
> series.
> 
> A **solid** aluminium capacitor has the advantages of tantalum without
> the catastrophic failure mode.
> 
> 
> 
>             Russell McMahon
> 
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

Send instant messages to your online friends http://asia.messenger.yahoo.com 
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist