Mathematician Sidney Darlington Dies

[John Young <jya@pipeline.com>]

NYT obit November 8:

Sidney Darlington, a Bell Labs mathematician who pioneered
the design of electronic circuits and whose formulas helped
launch rockets 300 times without error, died on Oct. 31 at his
home in Exeter, N.H. He was 91.

At Bell Labs, in Murray Hill, N.J., where he headed the 
mathematics research center, Dr. Darlington was ranked
alongside his colleague Claude Shannon for breakthroughs
in communications networks that foreshadowed the integrated
circuit and in turn computers and modern communications.

Dr. Darlington's discovery of ways to custom-design circuits
using precise mathematical specifications, a speciality now
called network synthesis theory, made him a leading authority
in electronic cirsuits for decades, said Dr. Ernest Kuh, a
former colleague who is now at the University of California
at Berkeley.

Before Dr. Darlington's work, circuits were designed in an
intuitive, ad hoc manner. His advances won him the highest
award in his field, the Medal of Honor of the Institute of
Electrical and Electronic Engineers.

At a chalkborad at Bell labs with three or four other rocket
guidance experts, he would scrawl equations that became
the basis for guiding the Air Force Titan I, the Thor-Delta
and dozens of other rockets.

His rocket guidance formulas could instantly plug in the
information from several sources -- the trajectory designed
to launch a staellite, the data from radar that tracked the
rocket, and the instruments in the rocket itself -- and
could then return a flow of commands to the rocket.

Always a tinkerer, Dr. Darlington in the 1950's spent a
weekend at home playing with a new gadget, the transistor.
Trying to get more gain from an amplifier the size of a kernel
of corn, he found a way to combine two or more transistors
in one chip, an idea that became the Darlington Compound
Chip and pointed the way toward integrated circuits.

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