On Sat, 18 Sep 2004, Win Wiencke wrote:

> <Dave King observed in part>
>> Isn't week 54 in 92 (as there
>> are only 52 in a year we knew this) it is most likely a batch code. ie
>> batch 54 of 1992.
>
> As good a guess as any.
>
> I have no idea how many "batches" a foundry might make -- or even what would
> consitiute a batch (a single wafer? a single crystal? a single etching?).
> 54 "batches" suggests that the chip was made in some volume.
>
> I'd be curious about what in the foundry process lends itself to a tracking
> number (as distinct from a mask number).

Some people simply count the batches, period. Others cuont the batches per 
year. Others put in a datecode. The latter is most likely for 'evergreen' 
chips (manufactured over several years). I believe that the telecom chip 
the op was seeking was not an evergreen so it could have been the batch 
number, period.

Peter
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