Connect with us

Do ceramic capacitors age?

Discussion in 'General Electronics Discussion' started by ubercool, Nov 30, 2012.

Scroll to continue with content
  1. ubercool

    ubercool

    27
    0
    Nov 6, 2012
    Do ceramic capacitors age? If I have got a 29 year old device, at what value would a 220pF capacitor be now? Would it have crossed its tolerance limits?
     
  2. CocaCola

    CocaCola

    3,635
    5
    Apr 7, 2012
    Unless they have been subject to extreme conditions they should last many more decades/centuries without even blinking...
     
  3. Harald Kapp

    Harald Kapp Moderator Moderator

    10,609
    2,370
    Nov 17, 2011
    They will last, but they will show effects, too.
    How much depends on the type of ceramic. If you need long time stability use COG (NPO) ceramic. X7R capacitors will derate noticeably more with time and temperature.

    Also note that (especially high capacity) ceramic capacitors are voltage dependend.

    Read this overview for more detail.

    Harald
     
    Last edited: Nov 30, 2012
  4. Jotto

    Jotto

    120
    0
    Aug 24, 2012
    Ceramic, tantalums, mylar, polypropylene caps last a long time.

    Electrolytic capacitors start going bad when they are manufactured. Aging just sitting on the shelf. This is why you don't buy a bunch of them if you can't use them in a couple of years. The other types don't have this problem.

    Usually 5%, sometimes 2%, then special order 1%.. Usually I give a swing of 20% when I test them if its not a critical circuit.
     
    Last edited: Nov 30, 2012
  5. ubercool

    ubercool

    27
    0
    Nov 6, 2012
    The capacitors are a part of a tuning circuit which is made of variable ferrite core inductors, fixed values ceramic capacitors and DIP switches. This circuit is not giving its desired performance, which component is most likely to be faulty?
     
  6. davenn

    davenn Moderator

    13,674
    1,892
    Sep 5, 2009
    it depends, could be anything
    you havent told us anything about the circuit, or what you think its performance should be

    show us a circuit diagram of the circuit

    cheers
    Dave
     
  7. ubercool

    ubercool

    27
    0
    Nov 6, 2012
    The diagram is attached. Switches 2,3,5 of dip switch S2 should be closed and switches 1,2,4,5 of dip switch S3 should be closed if I want to receive a signal of 332kHz. However, the reception is poor, there is a lot of noise and the sensitivity is terrible. I have checked all the amplifier ICs, they are perfectly fine.

     

    Attached Files:

  8. ubercool

    ubercool

    27
    0
    Nov 6, 2012
    Hmmm?
     
  9. davenn

    davenn Moderator

    13,674
    1,892
    Sep 5, 2009
    I saw you were getting answers in another forum you posted this topic in so left them to sort you out. no point me repeating everything

    Dave
     
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

-