Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!iuvax!ndcheg!ndmath!milo
From: milo@ndmath.UUCP (Greg Corson)
Newsgroups: sci.electronics
Subject: "Super" capacitors == Batteries?
Message-ID: <1428@ndmath.UUCP>
Date: 5 Jun 89 16:48:49 GMT
Organization: Math. Dept., Univ. of Notre Dame
Lines: 27

I've been noticing a lot of these so-called supercaps...capacitors with
greater than 1 farad of capacitince.  Their main use seems to be a battery
replacement for CMOS ram or clock circuit backup.

 
I'm somehwhat embarassed to say that I've forgotten too much of my college
electronics courses to have a good "feel" for how much juce you can store
in one of these capacitors and how long you can discharge it at a fixed rate
before it's all gone.

I would appreciate it if someone out there could help me get a feel for this,
possiblly by equating one of these supercaps to simple battery terms.  Ie:
how many miliamp-hours of capacity one of these supercaps is equivalent to.

My application is a farely simple one...I want to run a blinker-LED off of
a supercap.  I was wondering if a 1 farad supercap would have enough juce to
keep a blinker-LED (I'm talking about the kind with the blinker built-in, no
external circuitry) going for 8 hours or so. 

If you've got the answer...please write!   Thanks!

Greg Corson
19141 Summers Drive
South Bend, IN 46637
(219) 277-5306 
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