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Reply To: | TechNet E-Mail Forum. |
Date: | Thu, 3 Jun 1999 16:53:57 -0400 |
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<lol> - Well, teaches me not to be more specific!
Thanks to all who replied about reversed and internally reversed
(built backwards) capacitors... I've seen those, and, unfortunately
that's not an issue here.
Electrical surges, including negative spikes has also been ruled out.
This issue is occurring on boards designed by different companies.
The problems are either in the manufacture of the cap's themselves,
or, our process is causing the failure mode of the caps either in
creating the problem or by aggravating an existing defect.
Thanks again!
Rob Green
---------------- Original Message -------------------------------
We are currently experiencing a run of tantalum polarized capacitor
failures. The caps are becoming resistive when voltage is aplied,
drawing current, and cooking up. Sometimes this is immediate,
sometimes over time.
This issue primarily is affecting 12VDC power busses, and involves
several different value and manufacturer caps. Common threads: 12V
circuits (the supplies themselves have been ruled out), polarized SMT
tantalum capacitors, 35V rated.
We have had the manufacturers involved and have exhaustively looked
into the issue. I know that there is a myriad amount of possible
contributors to this problem.
My question is simple: Have any of you experienced this before with
tantalum capacitors, and if so, what have you found?
Thanks in advance!
-------------------------------------------------------------
Robert D. Green - Supervisor, Test Engineering
Hadco - Value Added Manufacturing
e-mail [log in to unmask]
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