On 2016-Apr-23, at 4:15 PM, Jon Elson wrote:
> 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!)
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.
