The Enduring Legacy of Transistor
Current Switching Circuits
The following observations, and associated
references, have been included in this Oral History in order to provide a
current perspective on the historical importance of Hannon Yourke’s
pioneering work on the first transistor current switching/ECL
1. Summary Observation: The high performance
computer industry was dominated for many years by bipolar ECL based vector
processors until the mid 1990s, when CMOS performance finally began to
compete. “The Recent Revolution in High-Performance Computing”, Horst D.
Simon, Materials Research Society, Vol 22, Oct 1997.
LINK: ECL in High Speed
2. Summary Observation: Beginning in the 1960s, Motorola
announced the MECL line of ECL based integrated circuits, becoming a leader
in this high speed technology – target markets were supercomputers,
automatic test equipment and disk drive electronics. “GaAs ICs – they came, they went, they
came”, George Rostky, EETimes Millennium 2000 Series, The Century of the
Engineer: Misunderstood Milestones.
Rostky - GaAs ICs - EETimes
3. Summary Observation: H.S. Yourke’s emitter
coupled logic broke the nanosecond barrier for switching speed and was used
pervasively in high speed computing for many years to follow. “First
Bipolar ECL Logic Circuit, ISSCC 50th Anniversary Virtual Museum
– a showcase of 70 outstanding ideas spanning 50 years of solid state
circuits history” - IEEE International Solid-State Conference.