Connect with us

Real time clock basics

Discussion in 'Electronic Basics' started by Jack// ani, Dec 20, 2005.

Scroll to continue with content
  1. Jack// ani

    Jack// ani Guest

    Hi all,

    How do those RTC work...do they need external battery backup or
    something else to maintain time??

    Thanks
     
  2. Dan Hollands

    Dan Hollands Guest

    Some have internal batteries and some require external batteries

    Sometimes a very large value capacitor is used in place of external
    batteries

    Dan

    --
    Dan Hollands
    1120 S Creek Dr
    Webster NY 14580
    585-872-2606

    www.QuickScoreRace.com
     
  3. Jack// ani

    Jack// ani Guest

    Hi Dan,

    Thanks for reply...do internal battery need charging, how long do they
    last??

    Thanks
     
  4. Dan Hollands

    Dan Hollands Guest

    I don't know - never used one - just saw one at some point in a catalog

    --
    Dan Hollands
    1120 S Creek Dr
    Webster NY 14580
    585-872-2606

    www.QuickScoreRace.com
     
  5. You'll have better luck with a question like this if you actually use the
    other side of google - the web search.

    Try various things in the search box, like "Real Time Clock Batteries" or
    whatever search phrase you want to make up - you will be amazed at what's
    already out there.

    Admittedly, that's a lot colder and less fun than interacting with actual
    real live people, but huff! This is the sci.electronics.design group, not
    the sci.electronics.basics group, so we're all insufferable arrogant prigs
    who mercilessly flame anyone who asks an impertinent question.
    <pause for audience laughter>
    Was everybody able to discern that that was a joke? ;-)

    But in answer to your question, the only honest answer is, as usual, "It
    Depends." :)

    Good Luck!
    Rich
     
  6. Jack// ani

    Jack// ani Guest

    Hi Rich,

    If you can read properly.....the thread is posted in
    *sci.electronics.basics* not sci.electronics.design!!!! Dosen't that
    makes any difference....and turns what all you said useless!!!!!
     
  7. Jasen Betts

    Jasen Betts Guest

    yes.

    some are encapsulated with the battery,

    other use an seternal battery. these days a 3v lithium disc cell or a large
    capacitor is commonly used,

    In the past on-board NiCd rechargables and external battery packs been used
    as well.

    Amstrad even made a computer with an external battery compartment.

    Bye.
    Jasen
     
  8. Jasen Betts

    Jasen Betts Guest

    no, when the battery fails the unit must be replaced (or opened and the
    battery replced)

    about 5 years.

    the first signs of a failing battery is that the PC's real time clock starts
    losing time and then stops

    As the clock chip also stores the BIOS configuration info the next sign is
    corrupted config info.

    Bye.
    Jasen
     
  9. Rich Grise

    Rich Grise Guest

    Sorry, I won't bother you with any replies next time.

    Good Luck!
    Rich
     
  10. Mr. C

    Mr. C Guest

    Some have internal batteries and some require external batteries
    We are now using a 1 Farad super capacitor with our RTC. If you do
    not expect long power outages (like several weeks), the super cap is a
    nice way to go. It does not require replacement like a battery and
    can be permanently installed.

    On the other hand, if there are few power outages, a lithium battery
    would also work well since it has such a long shelf life. The
    supercap/RTC combination we use retains the time for outages well over
    one month.

    Lou
     
  11. Jack// ani

    Jack// ani Guest

    Hey Rich......I've no such intention, so keep posting!!
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-