Do ceramic capacitors age?

[ubercool]

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?

 

[CocaCola]

Unless they have been subject to extreme conditions they should last many more decades/centuries without even blinking...

 

[Harald Kapp]

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

 

[Jotto]

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.

 

[ubercool]

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?

 

[davenn]

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

 

[ubercool]

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.

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

 

[ubercool]

Hmmm?

 

[davenn]

Hmmm?

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