Hi Lou,

Phil's comments were correct.  Solid Tantalum capacitors do not require the
dielectric "reformation"  that is necessary after aluminum electrolytics
have been stored for a while.  There is no electrical shelf life of solid
tantalum caps.  The only real concern is solderability after several years,
but that's the case with any component.  And since you indicated that the
parts in question are already soldered onto boards, then solderability is
obviously not an issue.

Nancy Reynolds
KEMET Electronics





Lou Hart <[log in to unmask]>@ipc.org> on 05/09/2000 12:04:02 PM

Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond
      to Lou Hart <[log in to unmask]>

Sent by:  TechNet <[log in to unmask]>


To:   [log in to unmask]
cc:
Subject:  [TN] Shelf life of tantalum capacitors


TechNetters, anyone know of a shelf life for tantalum capacitors?  We use
some on our own designs here, and want to know how long boards can sit on
the shelf before these parts should be replaced.  Aluminum electrolytics
may be a year, according to my understanding.  Thanks for any comments.
Lou

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