[sdiy] Static Damage to ICs

[patchell]

    The problem with static damage is that a lot of times, nothing
happens at all, at least at the moment.  Static damage can manifest
itself much later (years sometimes) by a sudden unexplained failure.

    However, with opamps and the like, the failure is generally fairly
subtle.  For Fet opamps, a lot of time it increases the leakage current
in the inputs.  A TL072, while it does have fairly low bias currents, it
is really not all that low.  So, you may or may not notice the damage
right away.

    Another factor in Static damage is the size of the features.  At
work, I had to knock a few heads when the new gate arrays we started to
use were having a 50% failure rate.  Turns out they are very sensitive
to static.  I found this out myself when I forgot to plug myself in and
touched the board (while it was running), and it instantly stopped.
Blew the FPGA right now.

"Rhen, Kris" wrote:

>    Have a question.  What is the result of static damage to an IC?  I
> don't
> think I have any, just a purely informative question.  If I shuffle
> across a
> carpet and 'zap', say, a TL072 or LM13700 or the like, what happens at
> that
> electronic level?  What is the mechanism of damage?  How does the
> damage
> manifest itself when the IC is used?  Curious...  Thanks all
> KRIS
>
>

--
 -Jim
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