On 04/23/2016 05:46 PM, Chuck Guzis wrote:
On 04/23/2016 02:34 PM, Brent Hilpert wrote:
I was surprised by the early date code on the 7490s when I ran across
them in a piece of test equipment.
What was surprising to me is how quickly the industry standardized on
the TI 7400/5400 parts. Early (ca 1967) Moto databooks had MTTL I,
MTTL II and MTTL III that were essentially sui generis. By 1969, the
MC7400/5400 had pretty much taken over. Things moved really quickly
back then.
Lots of designers and system manufacturers were VERY leery
of adopting anything single-source.
When a number of chip makers (Nat Semi, Motorola, Signetics,
Fairchild) all jumped onto making compatible 7400 parts, the
industry had the confidence that parts in the series would
be available for a long time. Back in the late 60's, early
70's the industry was moving at a breakneck pace, and chip
families had very short lifetimes before their makers hopped
onto the next new thing. (Oh, yeah, you said the same thing
in the last sentence!)
Jon
