Return to Electronic Links page
Multilayer Ceramic Capacitors
Capacitor failure can have catastrophic effects. Between 1985 and 1988 when I was carrying out research I came across several instances where equipment had caught fire as a direct result of MLC capacitor failure. Here is a picture of a circuit board which was badly damaged when the 47nF decoupling capacitor next to an I.C. went incandescent.
In another instance an identical board assembly had a 25mm diameter hole burned right through it.
| 
| In a previous article I discussed MLC capacitor failure causes. Here is a picture of a capacitor which suffered thermal stress. We soldered the capacitor to a PCB by hand then plunged it into cold water. This is an extreme measure but we wanted to see what thermal stress cracking would look like. |
| 
| Here is a magnified view of the same capacitor. See the vertical fracture. |
| 
| And this is a cross-section of a capacitor which suffered similar thermal stress.
Note the crack which looks like the profile of a mountain. |
M.T. Pickering B. Eng.
Copyright ©1997 Martin Pickering
Version 1.2 updated on November 9, 1999
This file may be downloaded for private and personal use but NO part of it may be published in any form without the prior permission of the author. Return to Electronic Links page
