"they're only 20 years old, what are they doing
    failing this soon?? "

It all depends on a number of factors including the
original manufacturing 'proceses' of the fab (fabrication
facility) and methods  used to make the devices (types
of band wires, methods used to seal the die in the
package, how clean their 'processes'/processing
facilities were ...).

Semiconductor manufacturing is a lot like politics
or sausage making - you may appreciate the outcome
BUT the process itself is messy and you REALLY don't
want to know all the intimate details and pitfalls
of what it takes to 'make product'.

And this is aside from any abuse they may seen through
the years!

RF Jim (who spent sev. years at TI's "GaAs Facility")



----- Original Message -----
From: "Dale Botkin" <dale@BOTKIN.ORG>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Monday, November 04, 2002 11:19 PM
Subject: Re: [EE]: Power supply rework (again)


> Jim, Rick, thanks to you both.  I was hoping I wasn't going nuts.  Q1
> measures infinite resistance from E to C but not C to E.  I'm ordering a
> new pair of transistors tomorrow.  Lot markings are 8239 - Darned things,
> they're only 20 years old, what are they doing failing this soon??  8-)
>
> Dale

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