Jon Elson elson at
Wed Jan 31 12:56:26 CST 2018

On 01/31/2018 12:00 PM, Chuck Guzis via cctalk wrote:
> On 01/31/2018 06:00 AM, Paul Koning via cctalk wrote:
>> Wow, 10 years later, with faster chips, and still the same speed?  That's surprising.
> I believe that Honeywell went through a similar exercise at one point.
> An all-ECL redesign (details escape me) resulted in no appreciable
> improvement in performance.
I had a problem with a 16-bit binary counter not having 
enough frequency resolution, and looked at using ECL to be 
able to double the clock.  After much calculating, I found 
that there was not a huge improvement with the ECL.  And, if 
you went to 74S, Fast or 74AS, you could easily match the 
ECL 10K performance.  Now, there were a bunch of tricks that 
you could use with ECL that helped, like wired-OR instead of 
adding a tri-state buffer.  ECL had a notable advantage in 
1970, but as TTL derivatives continued to advance, that 
shrank to nothing.


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