Gary,

Our general derating guideline for solid tantalum capacitors is 50%  If  your using a 50VDC capacitor with 38VDC your bound to see failures.

Regards,
George
George M. Wenger
Reliability / FMA Engineer
Base Station and Subsystems Group
Andrew Corporation, 40 Technology Drive, Warren, NJ 07059 (908) 546-4531 [log in to unmask]


-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Gary Bremer
Sent: Thursday, April 28, 2005 10:27 AM
To: [log in to unmask]
Subject: [TN] Capacitor Failures


Has any one had any problems with Vishay Capacitor P/N 595D226X9050R2T failing?
From our electrical engineers statement the most common failure is during
in-circuit test.  This is conducted at ambient temperature & humidity.  These
capacitors are used to decouple an input voltage, which is set to increasing
values.  The failures have been occurring when a steady-state input voltage of
around 38 VDC is used.  When the voltage is left on, the chances of failure
increases.  For example, two different capacitors were blown when the input
voltage was left on for about 2 minutes.

--
Gary Bremer
Senior Manufacturing Engineer

Curtiss-Wright Controls Inc.
Embedded Computing -Subsystem

28965 Avenue Penn
Santa Clarita, CA 91355-4185
Main: 661.257.4430 extension 2170
Fax: 661.257.4782
e-mail: [log in to unmask]
Web: www.cwcembedded.com

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