James D. meinDl caught the low-power

+
medal of honor
wizard of watts
James D. Meindl caught the low-power semiconductor wave
when it was barely a ripple and brought gener ations
of gr aduate students along for an exciting ride
By Tekl a S. Perry
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james d. meindl, professor of microelectronics at the Georgia Institute of Technology,
It was the mid-1970s, and Meindl was a professor at Stanford
University, in California. His group had just paid more than
US $1 million for a shiny new epitaxial reactor, in which atoms
are deposited layer by layer to produce semiconductor devices,
usually experimental ones. It was the latest and greatest tool of
the day, and Meindl assigned one of his newest and brightest
students to see what it could do.
The department’s safety rules forbade students from working
alone, but that new student wasn’t much for following rules. One
night, working by himself, he opened a valve to let silane gas
flow into the reactor. Alas, he’d forgotten to purge the air out of
the chamber, and silane explodes on contact with oxygen. The
resulting blast ripped the reactor out of the wall. The student
was lucky to escape serious injury.
Clearly, he had to be punished. Meindl couldn’t bring himself
to do it, so he prevailed upon a colleague, who banned the young
man from the laboratory for two weeks.
Even today, Meindl beams when discussing that brash young
researcher. And well he might: that student, T.J. Rodgers, went
on to found Cypress Semiconductor Corp., in San Jose, Calif. Last
year Cypress had $886 million in revenues. “Those were the good
old days, when well-meaning accidents were just punished by a
slap on the wrist,” Rodgers says today of the incident.
Before he met Meindl, Rodgers recalls, he had never worked on
big problems involving the coordination of many individual research
efforts. He had never heard of Silicon Valley and had never known an
engineer who had started a company. Meindl brought him into this
incredibly exciting world, he recalls, and “it was thrilling.”
Meindl says of his students, “My reward is to see them succeed.” He’s been very well rewarded. Rodgers was one of some
80 engineers who did their graduate work under Meindl’s tutelage. Among the others are William Brody, president of Johns
Hopkins University, in Baltimore; Levy Gerzberg, president of
Zoran Corp., the Silicon Valley company whose signal-processing
hardware is in just about every digital camera today; and Richard
Swanson, who founded SunPower, a pioneer in high-efficiency
solar cells, which was purchased by Cypress in 2002.
Another Meindl disciple, L. Rafael Reif, provost at the Mas­
sa­chusetts Institute of Technology, in Cambridge, says, “I try
to emulate everything about him: I listen to everyone. I try to
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this page and preceding page: David stuart
says the most important part of his job is ­making graduate school fun and exciting. Lots
of professors make the same claim, of course, but Meindl, the winner of the 2006 IEEE Medal
of Honor, has an explosive story to prove it.
find the kernels of truth in what people are saying. I try always
to find the glass half full.”
Gerzberg credits the success of Zoran to the lessons he
learned from Meindl. And Jim Plummer, dean of engineering at
Stanford, declares, “There is no other individual who has had
more of an impact on my career than Jim Meindl.”
Development Laboratories, in Fort Monmouth, N.J. [see photos,
“One Haircut, Three Decades”]. It turned out to be “the most
fortunate unwanted experience” of his life. For one thing, he met
his future wife, Frederica. She was an administrative assistant
for Meindl’s supervising officer. They had their first date that
October, and the rest, Meindl says, is history.
Encountering his life partner wasn’t the only happy surprise
at Fort Monmouth. There was also his work assignment, which
turned out to be a lot more interesting than he was expecting: he worked with integrated circuits—a field then barely
six months old.
Just after Meindl arrived at the R&D labs, the Army awarded a
research contract to Dallas-based Texas Instruments Inc., where
Jack Kilby had built one of the first ICs. Meindl became the technical liaison for the project. He met Kilby in November; a few
months later, early in 1959, he visited Gordon Moore and Robert
Noyce at Fairchild Semiconductor Corp., in Palo Alto, Calif. Those
three pioneers taught Meindl about the nascent field, and he began
his own research, trying to figure out how to make an IC operate
at a power level so low that it could be used inside a helmet as
part of a radio receiver. Meindl stayed at Fort Monmouth for eight
years, two as an Army officer and six more as a civilian.
For many professors, it would be legacy enough to have sent
so many students into the hallowed halls of academia and the
boardrooms of Silicon Valley. But for Meindl, it’s just part of
the story. He also did pathbreaking research in the design of
low-power circuits and in the interconnects that link blocks
of logic in a chip. It was for those achievements—specifically,
his “pioneering contributions to microelectronics, including
low-power, biomedical, physical limits, and on-chip interconnect networks”—that he was awarded this year’s IEEE Medal
of Honor.
And yet, when Meindl started out in technology, half a century ago, semiconductors were little more than laboratory curiosities. Enrolling in 1951 at Carnegie Institute of Technology
(now Carnegie Mellon University), in Pittsburgh, he planned to
get a degree in power engineering and then design heavy electrical equipment at Westinghouse Electric Corp., where his father
worked. But in 1955, Carnegie’s graduate power engineering In the early 1960s, hardly any engineers outside the military
department abruptly vanished: one professor quit and another were interested in minimizing the power used by electronics.
changed fields.
Metal-oxide semiconductors (MOSs), which consumed signifiMeindl, then just starting graduate school, was open to sugges- cantly less power than their bipolar predecessors, were in their
tions about what to do next, and Professor Edward Schatz had one. infancy and had stability problems. But as the decade went on,
The U.S. military was trying to improve its communications sys- the growing popularity of the quartz watch and the in-ear heartems and needed an energetic graduate student to analyze the loss ing aid, both of which could accommodate only tiny batteries,
of radio-frequency signals transmitted through coaxial cables. The brought attention to the need for low-power circuits. Still, when
goal was to come up with equations that would describe the signal Meindl published his first and only book, Micropower Circuits
loss and allow engineers to build better cables. Meindl solved the (Wiley), in 1969, you could count the number of copies sold on
problem in 24 months, in the process becoming quite well versed two hands.
in Maxwell’s equations, the set of four equations describing the
But Meindl was onto something. “Even at a time when few
behavior of electric and magnetic fields and their relationships people worried about power consumption, he thought it was an
to each other and to electric-charge and electric-current density. interesting area to explore, because it would eventually become a
Facility with these equations, which are considered to be
the foundation of electrical engineering, gave Meindl the
insights he needed to understand that latest electronic
marvel, the semiconductor.
Position: Joseph M. Pettit Chair Professor
Patents: about 10
Meindl got his Ph.D. in electrical engineering in
of Microelectronics; Director, National
Corporate board
1958. He took a job at Westinghouse, as he’d planned
Nanotechnology Infrastructure Network; both
memberships: all along, but not as a power engineer. Instead, he
at Georgia Institute of Technology, Atlanta
SanDisk Corp., Zoran Corp., became one of the company’s first semiconductor
Date of birth: 20 April 1933
Stratex Networks Inc.
engineers. His initial assignment was to use siliconBirthplace: Pittsburgh
Most recent book read:
controlled rectifiers—diodes that must be triggered
The Innovator’s Dilemma, by Clayton by a voltage pulse in order to conduct current—as
Height: 180 centimeters
M. Christensen (Harvard Business part of an electronic system that would manage the
School Press, 1997)
Family: Wife, Frederica; control rods of a nuclear reactor. He loved the job. “I
children, Peter and Candace
got to buy and burn out transistors that cost about a
Favorite composer:
thousand dollars each,” he recalls. “And I learned that
Cole Porter
Education: B.S., M.S., and Ph.D. in electrical engineering can be a lot of fun.”
electrical engineering from Carnegie Computer: IBM ThinkPad
Unfortunately, the fun only lasted about a year. In
Mellon University, Pittsburgh, in 1955, 1956, and 1958
Favorite restaurant:
1959 he received a summons from the U.S. Army. It
Park 75, Atlanta
was payback time. Meindl, a member of the Reserve
First job: Usher, Terrace Theater, Officers’ Training Corps program during college, went
East Pittsburgh
Favorite movie: True Grit
on active duty.
First technical job: Insulator Car: Lexus sedan
“Here I was, working,” he recalls. “I had a great
tester,
Westinghouse
Electronics Corp.,
job, I had bought my first new car, and I just felt that
Organizational memberships:
Pittsburgh
the world is a really good place. And suddenly, here
IEEE (Life Fellow), U.S. National Academy comes Uncle Sam.”
Oddest job: of Engineering, American Association Blacksmith’s helper
for the Advancement of Science
He ended up at the U.S. Army Signal Research and
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big issue,” Plummer says. And so it has: laptop
computers, cellphones, and iPods illustrate that
product design today is all about reducing power
consumption and extending battery life.
By 1966, several professors at Stanford were
encouraging Meindl to leave New Jersey and
join them in California. In 1967, John Linvill,
then chair of the electrical engineering department at Stanford,
made Meindl an offer he couldn’t refuse. Linvill had come up
with an idea for a system that would let blind people—including Linvill’s own young daughter, Candace—read. It would use a
camera to take a picture of the letters on a page and then translate
that picture to a tiny pad of vibrating pins. With training, Linvill
reasoned, a blind person would be able to place a finger on the
pad and decipher the text. But making such a device portable and
useful required two custom-designed, low-power chips. One chip
would act as the image sensor—a solid-state camera, basically, at a
time when they were experimental. The other chip would operate
at a high voltage to vibrate the tactile array, consuming as little
power as possible to prolong battery life.
Meindl worked on the project for about a year, along with
several graduate students, including Plummer.
“We had significant problems,” Plummer recalls. They were
using MOS devices in a high-voltage application—which no one
had done before. After a lot of trial and error with the voltage levels, they finally found one that was high enough for the
vibration to be felt by the user and yet low enough to keep the
devices from burning out.
The group dubbed the device the Optacon, for optical-to­tactile converter, and demonstrated it for the first time at the 1969
International Solid-State Circuits Conference, in Philadelphia.
Linvill’s daughter Candace demonstrated the converter, and
she got a standing ovation. “That,” Meindl says, “was the most
thrilling moment in engineering work that I have ever had.” He
later named his own daughter Candace to honor Linvill’s daughter and the moment.
In 1970 Linvill, Meindl, and their team rolled the technology
out into a company, Telesensory Systems Inc., now a division
of the Singapore company Insiphil. Telesensory produced tens
of thousands of the devices and sold them around the world.
Today, text-to-speech converters have supplanted the Optacon,
but it was an important aid in its time.
Telesensory never made its founders a fortune, but that
didn’t bother Meindl. Throughout his career, he says, he and
his co-workers have always selected “areas that could have the
most impact.”
Inspired by that moment at the 1969 conference, Meindl asked
a group of his Stanford students to develop novel low-power
sensors and circuits for use in medical research. Gerzberg, who
was part of the group, recalls that challenges were everywhere: in
signal-processing algorithms, in circuit design, in chip fabrication, in systems integration, and in coordinating with medical
researchers. Gerzberg also remembers that Meindl’s enthusiasm
never wavered. Gerzberg says, “Once I gave him a demo of a
prototype I had built, the first time I had it working, and he
actually stood up and clapped his hands for several minutes. He
always made me feel so good.”
The students built sensor packages that could be implanted
in research animals, transmitting physiological data while the
animal went about its normal activities. A medical researcher
inserted one such sensor package in a monkey fetus still in
the mother’s uterus. The monkey mother eventually went into
natural labor; the researcher then wirelessly activated the sensor package to provide the first detailed information about the
baby’s physiological experience during birth. Meindl and several graduate students designed another device to measure the
velocity of blood cells as they flowed through different parts of
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james D. meindl (3)
ONE HAIRCUT, THREE DECADES:
James Meindl, as photographed by his
wife-to-be in 1959 [left]; demonstrating the Optacon optical-to-tactile
converter with Candace Linvill during
the 1969 International Solid-State
Circuits Conference [center]; and with
President Jimmy Carter at Stanford
University in the early 1980s [below].
the body. Meindl attended a procedure in which a surgeon used
this device to monitor the progress of a heart valve replacement;
after the artificial valve had been sewn into place, the flowmeter
flagged a problem with the new valve, and the surgeon quickly
replaced it, possibly saving the patient’s life.
Another achievement at Stanford hasn’t saved any lives, but it
has saved many designers countless hours of R&D time. In 1971,
Meindl posed a simple question to graduate student Swanson:
theoretically, what is the lowest possible voltage at which an arbitrary complementary metal-oxide semiconductor (CMOS) circuit
could operate? Knowing this value would prevent circuit designers from exploring dead ends—techniques that would drive the
voltage so low the designs wouldn’t work. Swanson determined
that the minimum voltage is a multiple of the thermal energy of
the material, with that multiple changing in a predictable way
depending on the temperature of the material. Circuit designers
the world over still use that fundamental limit.
By the mid-1980s, after nearly two decades at Stanford, Meindl
was ready for a new challenge. “I’d had a number of rewarding
experiences,” he says. “The question was whether I was going
to do this for another two decades or try something drastically different.”
“Drastically different” won. In 1986 he moved to Troy,
N.Y., to become the provost of Rensselaer Polytechnic
Institute (RPI). The job appealed to Meindl for two reasons. First, he saw being a provost as an intellectual
smorgasbord—no longer would he be simply interacting
with his engineering colleagues: he would learn about
new ideas in every department. Second, he was excited
about the idea of having a discretionary budget to fund
ideas and reap their returns.
Life as a provost, however, was not as rosy as Meindl
had anticipated. Colleges across the United States had
begun feeling the waning of the post–World War II baby boom, as
the so-called baby bust took its toll on their applicant pools. And
RPI, more than most U.S. universities, lived or died on tuition
income. So for seven years Meindl cut departmental budgets and
cut them again. For a guy who liked to make people happy, it was
not a happy time. Still, he kept his cool and deftly handled the
faculty, recalls Robert Loewy, then a professor at RPI.
Meindl kept a hand in electrical engineering by advising two
graduate students—Vivek De, now manager of low-power circuit
technology at Intel Corp. in Hillsboro, Ore., and Bhavna Agrawal,
now team leader for analog computer-aided design at IBM Corp.
in Zurich, Switzerland. It was a bright patch in an otherwise
dark stretch. “Last time I heard,” Meindl beams proudly, “one
of those students [De] had the second-largest number of patents
of any Intel employee.”
In 1993, enough was finally enough. Meindl went back to
doing what truly makes him happy: teaching and research, this
time at the Georgia Institute of Technology, in Atlanta.
Today, at 73, Meindl is a happy man again. He is pursuing
one of his long-standing interests: optimizing the arrangement
of interconnect wires that connect blocks of logic circuitry on
a chip. The Interconnect Focus Center, in Atlanta, a major R&D
effort he organized eight years ago with 13 U.S. universities,
recently demonstrated a new high-speed optical modulator
mechanism for silicon chips, a key component in future optical interconnects.
Says Plummer, “Back when most people had yet to recognize that interconnects would be a limiter in silicon chips, Jim
launched a national program to tackle the issue.”
Indeed, the semiconductor industry has come around to
Meindl’s way of thinking. Engineers today recognize interconnects as a major impediment to the performance trajectory
that microprocessors have been on for the past 35 years. It
is the wires, not the transistors themselves, that are sucking up power, threatening chip performance, and dragging out
design cycles. In today’s billion-plus transistor chips, which
have multiple layers of wires connecting transistors and
many kilometers of interconnects per square centimeter, the
wires cost more than the transistors (see “Chips Go Vertical,”
IEEE Spectrum, March 2004).
So far, Meindl and his Georgia Tech team, most prominently
Jeff Davis, a professor there, have come up with a mathematical method to predict the distribution of interconnect lengths
within a chip. That is, given the size of a network of logic blocks
that must be wired and a set of possible lengths of each wire,
a designer can predict how many wires are likely to have each
length. The designer can use that information to select the
optimal widths for the wires of each length for maximum performance at the lowest cost before beginning to actually lay
out the chip. Meindl’s group is also trying to find ways to use
tubelike interconnects to remove heat from a chip; such wires
“Back when most people had yet
to recognize that interconnects
would be a limiter in silicon chips,
Jim launched a national program
to tackle the issue”
www.spectrum.ieee.org would move cooling water in and out of the chip using a nascent
technology known as microfluidics.
In between his research and teaching, Meindl finds time to
run the Focus Center and also act as Georgia Tech’s site director
for the National Nanotechnology Infrastructure Network. And
he’s on the boards of three companies: SanDisk, Zoran, and
Stratex Networks.
Eight years past the traditional retirement age, Meindl is not
thinking of slowing down anytime soon. Nanotechnology and
its potential for pushing the envelope of chip design beckons.
In one project, he and his students are trying to wire chips with
carbon nanotubes instead of copper traces.
But still, fundamentally, it’s about the students. Serving on
boards, Meindl says, makes him a better graduate advisor, because
it helps him understand how companies operate, what research is
needed, and what opportunities await new graduates. Involvement
with large research cooperatives means he can keep track of activities at a host of universities and spot opportunities for his students
to become innovators. And he really needs to understand nanotechnology, he says, because “it is going to infest every branch of
engineering. Students will have to know about it to use the latest
developments, no matter what area of technology they pursue.”
Continuing to challenge himself daily in the field he loves,
Meindl forges ahead. His busy schedule keeps him on the go,
from classroom to boardroom to research lab. As he passes
through a hotel lobby on a chilly February day, he has a personal greeting and compliment for every one of the hotel staff
members, leaving a trail of smiles in his wake. For Jim Meindl,
it’s still about making people happy. n
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