Article View: sci.electronics
Article #21708Re: "Super" capacitors == Batteries?
From: David Chapman
Date: Thu, 08 Jun 1989 04:19
Date: Thu, 08 Jun 1989 04:19
19 lines
1439 bytes
1439 bytes
In article <1428@ndmath.UUCP> milo@ndmath.UUCP (Greg Corson) writes:
>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.
>
>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.
You can't get enough power out of a supercap to light an LED. As has been
noted before in an earlier thread, the internal resistance is too high. CMOS
RAMs and clocks need only microamps to keep them going. That's why these
things have found a market.
--
David Chapman
{known world}!decwrl!vlsisj!fndry!davidc
vlsisj!fndry!davidc@decwrl.dec.com
Technical Details
Message-ID:
<15244@vlsisj.VLSI.COM>Path:
arc1-ca.pugleaf.net!utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!apple!versatc!leadsv!practic!vlsisj!davidcReferences:
<1428@ndmath.UUCP>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!apple!versatc!leadsv!practic!vlsisj!davidc From: davidc@vlsisj.VLSI.COM (David Chapman) Newsgroups: sci.electronics Subject: Re: "Super" capacitors == Batteries? Summary: no, you can't Keywords: supercaps, LEDs Message-ID: <15244@vlsisj.VLSI.COM> Date: 8 Jun 89 04:19:01 GMT References: <1428@ndmath.UUCP> Reply-To: davidc@vlsisj.UUCP (David Chapman) Organization: VLSI Technology Inc., San Jose, CA Lines: 19