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Re: Apple IIGS Memory Expansion Card question.
Bill Garber wrote:
"Scott Alfter" <salfter@salfter.diespammersdie.dyndns.org> wrote in message
news:2j14e.26763$v26.9257@fed1read06...
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: In article <EZadnWs3DfPh7s3fRVn-ig@comcast.com>,
: Michael J. Mahon <mjmahon@aol.com> wrote:
: >Bill Garber wrote:
: >> I think I have a set of 24 loose ones sitting in a drawer plugged into
: >> styro that you are welcome to for $10 plus postage.
: >
: >Danger!
: >
: >Don't use styrofoam for storing ICs. Though it provides
: >mechanical support for the leads, it is an insulator that
: >promotes ISD damage rather than protecting.
:
: One method I've seen used for storing/shipping chips is to put a bit of
: aluminum foil between the chip and the foam. That should connect all of
the
: pins together while still providing for relatively cheap and available
: storage.
Never thought of that, Scott. That would balance the static over all of the
pins keeping it out of the actual circuits. Great Idea! Thanks for that.
In that case, omit the foam and just wrap the IC in aluminum foil.
Aluminum foil is a good shield _after_ it is wrapped around the IC,
but as it is _being_ wrapped, it is a great electrode to collect
charge from the styrofoam and deliver it to the first pin touched.
If you really trust that _every_ pin is making good contact with
the foil (I don't), you could pre-wrap the IC, then try to insert
it into foam, but why take the chance?
IC leads are quite sturdy, and, unless you are mailing them, I see
no reason to insert them into anything while they are sitting in
boxes or drawers. The occasional bent pin is a fact of life which
is easily remedied, while the occasional ESD damage is not.
The desire to insert ICs into foam seems to originate with the use
of _conductive_ foam. That's the only kind of foam for which the
practice can be recommended.
One of the reasons that there are so many superstitions about IC
storage is 1) the repeated warnings about ESD damage, and 2) the
relative robustness of _most_ ICs agains ESD damage. This causes
people to regard ESD damage as unavoidable, and that whatever
practice they have used is the reason that they haven't had
(too much) of a problem.
The actual situation is that if you find more than one in 10,000
ICs to be bad after storing them, then the problem is the way
that you are storing them.
-michael
New Applesoft BASIC interface for NadaNet networking!
Home page: http://members.aol.com/MJMahon/