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Topic: ECL (Read 921 times) previous topic - next topic

JoeN


I think that's a _CMOS_ chip with SiGe ECL-style output stage (which is LVDS basically).  The low input current
specs make it clear it's not ECL throughout!

The speed comes from using SiGe transistors in the output stage...


Isn't that the best of both worlds then?  If it achieves those speeds, who cares how it does it.  What is interesting to me, not knowing jack about this, is how low the level of integration is.  With only one gate or a 2:! mux on a chip, I would think you would have a board of these things before you have implemented something useful (a counter perhaps?) which then adds back a bunch of delays just because of trace lengths.  What is this used for?  Why did they never implement something like an 8-bit counter, shift register, or D-type flip-flops or something like that?
I have only come here seeking knowledge. Things they would not teach me of in college.

retrolefty

They use to be used  a lot as input prescaler dividers ( a divide by 10 decade counter was popular) for frequency counters up to 1200 Mhz or so. They sucked up a lot of Vcc current and ran plenty hot, but they were the speed burners of their day. Motorola was a big supplier of ECL chips as I recall.

Lefty

JoeN


They use to be used  a lot as input prescaler dividers ( a divide by 10 decade counter was popular) for frequency counters up to 1200 Mhz or so. They sucked up a lot of Vcc current and ran plenty hot, but they were the speed burners of their day. Motorola was a big supplier of ECL chips as I recall.

Lefty


Was that made out of discrete chips like this or did they have something with a better level of integration?
I have only come here seeking knowledge. Things they would not teach me of in college.

AWOL

Some of the earliest ICs were ECL, I believe.
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

retrolefty



They use to be used  a lot as input prescaler dividers ( a divide by 10 decade counter was popular) for frequency counters up to 1200 Mhz or so. They sucked up a lot of Vcc current and ran plenty hot, but they were the speed burners of their day. Motorola was a big supplier of ECL chips as I recall.

Lefty


Was that made out of discrete chips like this or did they have something with a better level of integration?


The earliest used simple flip-flops wired as counter/dividers, but there were more complex counter/divider chips available in time. I recall using a 95H90 decade divider good for 250Mhz or so in the 70s.

Lefty

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