On May 25, 20:19, William R. Buckley wrote:
> Steve Leach said:
>
> > If you could humor my electronic ignorance, what exactly
> > is a tantalum cap and how does it differ from a normal
> > capacitor? I was never before aware that there could be
> > more to a capacitor than plates (or foil) and an
> > electrolyte. How can a capacitor have a polarity?
>
> Not an electrolyte, an insulator. It is the inability to
> conduct electrons which gives the capacitor its ability to
> collect electrons.
> [...] Now, by being ionic, these electrolytes
> are well suited to the conduction of electron flow. This
> is most definately not the kind of behavior which you wish
> to obtain from a capacitor.
Not from a capacitor as a whole, but if you look inside the "black
box"... The discussion was about electrolytic capacitors. Of course
they have an insulator (the oxide on the aluminium foil anode) but they
also have an electrolyte (which is the cathode), and indeed wouldn't
(don't) work without it. It's the ability of the electrodes to conduct
electrons that give the capacitor its ability to store them.
--
Pete Peter Turnbull
Network Manager
University of York
Received on Tue May 27 2003 - 12:47:05 BST