Magnus Danielson magnus at
Mon Mar 2 21:11:00 CET 1998

>>>>> "c" == cyborg0  <cyborg0 at> writes:

 c> Magnus Danielson wrote:
 >> Still lacking a replacement source for some 74C components that needs
 >> to run of +12 V... the 74HC familly isn't much of a help. Anyone
 >> remember the 74C familly?
 >> Cheers,
 >> Magnus (Still learning from the past)

 c> ok.. heres the chips I need!! According to the ancient Malvino digital
 c> IC text: the 74CXX family... Great, seems as though you cant find them
 c> anymore too..
 c> :((

Well, one thougth that just springed to mind was to map the 74CXX
chips onto the 4000 familly, in some cases I suspect (I haven't
checked) that you can find a pin-to-pin mapping.

I have some 74CXX stuff in a Eventide Harmonizer H949 which I am
hoping isn't going to give up the smoke until I have a set of
replacements just sitting and waiting for it.

The same harmonizer is a bastard of ECL, TTL, CMOS and analogue. We
are talking DBX companding, funny A/D and early DRAMs. 48 bit wide
"command-bus" from TTL PROMs, AMD 2901 bitslices... system-clock at
105 MHz and CV and tone-tracking input ... all dating back to 1979.
Dual D/As, dual SSB generators... it can make some wounderfull effects
when it works...

BTW. I looked up in my RCA CMOS catalogue on series, they had two: A
and B. A where Vss +3V to +12V and B where +3V to +18V. The B series will
meet the requirement of EIA/JEDEC Tentative Standard No. 13B which has
recommended Vss at +3V to +15V.

So, now you have all of the +12, +15 and +18 that you had heard of!
Bottom line is, check properly!


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