Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Ceramic Capacitor Burnout

Status
Not open for further replies.
V

varaprasadmalisetty

Newbie level 2
Joined
Aug 25, 2011
Messages
2
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,296
Hello Folks,

I am having a problem with my DC-DC convertor board(24vdc to 12vdc/3A), where my ceramic capacitor is burning out after a long time run in the field. Due to that, fuse is blowing off and i/p protection mosfet also failing. After replacing all with new ones, the board is working normal. Again samething is happening after long time run in the field. I am unable to find the root cause.Can somebody help me to sort out this problem.


88_1314274903.jpg


:arrow:

Thanks in Advance,
Varaprasad.
 

At first, you should check capacitor voltage and current ratings.

It's seems like to be a rather large part (as far as we can guess from the blurry picture). So there may be a problem of micro cracks during solder, that developed to a short over time.
 

Thanks for the reply FvM,

But if the problem is with Voltage and current ratings, then at same place i am using same kind of capacitors 3 in parallel among them, everytime only a particular single capacitor is burning. Is there any chance of issue with PCB layout.


Regards,
Vara.
 

Is it always the capacitor at the same position that fails (in case of the capacitors are in parallel, but not close together)? Are you able to make a better photo?
 

- if the capacitors are connected in parallel (input or output filters of the buck converter), the current share may be different due to layout facts
- capacitor overtemperature may be different due to other components, check with an IR camera or a thermometer
- mechanical stress during solder can be different according to PCB geometry
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top