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DPRG: Logic Family Comparison Chart and example problem between fa

Subject: DPRG: Logic Family Comparison Chart and example problem between fa
From: Kipton Moravec kmoravec at airmail.net
Date: Wed Aug 25 15:23:54 CDT 1999

john.r.strohm at bix.com wrote:
> 
> >)The above is not a good approach for driving bipolar TTL.
> >
> >While this is a true statement, and I had the same sentiments, it's
> >probably not helpful at this point. I didn't think he had the option of
> >redesign, but rather to MAKE THE CIRCUIT WORK.
> 
> Yeah, you're right.  I saw that emitter follower trying to drive TTL,
> barfed all over the keyboard, and started writing before I read the part
> where he said he'd already gone out to fab and then stuffed the boards
> before he'd completed his prototype testing and found the problem.
> 

O.K. I screwed up.  But the first thirty production worked.  They used
74HC165 chips.  There was a typo and the next 100 used 74LS165.  The
board did not change at all between the two runs.  At this point it was
determined it would be cheaper to change two SIPS than 3 74LS165s.  The
decision is pure economic.

It is not like I built 100 boards, with no prototype.  We are past that,
the prototype worked, first production was 30 boards that worked, and
the screwup happened in the second production run.

Kip

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