[sdiy] Static Damage to ICs

[epeasant at telusplanet.net]

Hello, Kris,

>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

The pulse of electricity caused by the zap of discharge has an extremely high
peak current due to the high voltage of the static charge. This high current
melts and fuses the electrical conductors in the chip, sometimes completely
destroying a section and sometimes just partially damaging it, allowing it to
continue to function but to fail at some random moment in the future. Since
the actual path of the current pulse cannot be predicted (just like like lightning,
a similar phenomenom), the resultant chip damage also cannot be predicted. So
the functional symptoms of the damage can range from nothing apparent at all
to complete chip failure, with anything in between possible.

I have actually opened up static damaged ICs and identified the melted area
on the chip itself. It is quite easy to see with a decent microscope.

Take care,
Doug

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The Electronic Peasant

www.electronicpeasant.com