I guess my first question is; If the datecodes currently mean different
things depending on the manufacturer, why not standardize what datecodes
really mean rather than get rid of them?

The paper talks about all the advances that have been made understanding root
causes concerning solderability issues, improved storage and handling
methods, etc., then why do I continue to get moisture sensitive components
from distributors in un-sealed packaging? But that's another issue...

A recent issue here at my facility underscores the importance of a datecode
on the part. We build an assembly for a customer that uses three 240-pin QFP
DSP's from a well known manufacturer. So far, we've built-up over 200
assemblies for our customer. We shipped the assemblies to our customer and
they integrated them into the higher level assembly, and discovered they
don't work...not communicating at all with the rest of the system.

Numerous phone calls to the manufacturer trying to find out what the problem
could be resulted in "Nothing has changed with the part, the die hasn't
changed, nothing..."
Funny thing was our first pre-production shipment of the assemblies worked
fine!!

After looking a little closer, the first lot of assemblies contained DSP's
that had a datecode that was 2000 or earlier, everything that's failing are
later...but still, according to the device manufacturer; "Nothing has
changed..."

If there wasn't a datecode on the part, we wouldn't know what we could put on
the assemblies and work. There is a lot of effort being expended to try and
isolate what the problem really is (with no help from the device supplier),
but for now we need to find parts that work so that it doesn't shut down
production, the only solid way (for now) is to find parts within a certain
date code.

Now I'm faced with the possible task of reworking 200 assemblies, each with
three 240-pin QFP's, with a early datecode part...fun stuff I know.

-Steve Gregory-


> IPC has become aware that the National Electronics Distributors Association
> (NEDA) has posted a white paper discussing the proposed lifting of date
> code restrictions and they have requested comments from end users as well
> as component suppliers and distributors. The paper can be viewed at <A HREF="http://www.nedassoc.org/whitedat.html">
> http://www.nedassoc.org/whitedat.html</A>.
>
> Comments can be provided to me on or off net; we'll compile them and
> forward to NEDA. If you comment to NEDA directly <A HREF="mailto:[log in to unmask],">[log in to unmask],</A> please
> cc: me on your reply <A HREF="mailto:[log in to unmask]">[log in to unmask]</A>.
>
> Cordially
> Jack
>