24 Apr
2016
24 Apr
'16
2:05 a.m.
On 2016-Apr-23, at 4:15 PM, Jon Elson wrote:
On 04/23/2016 05:46 PM, Chuck Guzis wrote:
Fellow here did some research into the 181 history and came to a similar conclusion:
http://ygg-it.tripod.com/id1.html
He suggests TI being the first to contract for a second-source sent the buyers (esp.
military) to the 7400 series.
On 04/23/2016 02:34 PM, Brent Hilpert wrote:
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!) 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.