From the very beginning, "I was intrigued by anything having a CRT display and knobs to control it—the man-machine interface," says BarrieGilbert. At 22, he achieved a major milestone in oscilloscope architecture. By combining waveform sampling techniques with conventional real-time oscillography in the one instrument, it became possible to view phenomena over time spans from seconds down to nanoseconds.
Today, sampling is commonplace, but in the 1950s this was pioneering territory. In an unprecedented step, he replaced vacuum tubes with transistors for most of its circuitry. "I used the same layout as a Tektronix scope of the time. But inside it was totally different: a veritable tour de force. I keep a photo of it in my office. I'm proud of that achievement, not only for its practical value, but because I took the initiative to do what wasn't required of me." This "Do—don’t wait to be asked" mantra has energized Gilbert throughout his career.
Asked what was the best advice he ever received, he said it was "Go West young man!" In the 1960s, Great Britain was still an authoritarian society. "People expected to be told what to do; and managers, experienced or not, felt it was their job to tell them. I knew from my own experience what needed to be done, and when it was, I pursued initiatives no one knew about."
The bipolar transistor, he says, was a discovery, not an invention. Likewise the translinear (TL) principle was just waiting to be noticed. "It's about cells for the synthesis of nonlinear functions, using transistors connected in loops," says Gilbert. "TL is the basis for endless clever tricks, found in diverse variants in most analog ICs today. The key property of the bipolar junction transistor, its fundamental logarithmic/exponential behavior, was unavailable in the vacuum-tube era, and is only vaguely expressed in CMOS. I say at short courses that translinearity is so valuable that one can base a career on it—and I did!"
It's exploited in all of Gilbert's products—"pint-sized analog computers." The AD8304, for example, measures the power in an optical fiber via photodiode current over the range of 160 dB. The AD8362 computes the root-mean-square value of arbitrary signal waveforms up to microwave frequencies. They provide measurements of power scaled directly in decibels, with precise and stable calibration—hallmarks of Gilbert's ICs.
Success, Chance, and Enlightenment
A passionate believer in enlightenment as the key to world peace, Gilbert says that given 15 minutes with President Bush he'd advise him to "intensify his awareness of the vital role of education, and act on the realization of how crucially and profoundly it shapes the nation's destiny."
He adds "You might try entrusting the optimal allocation of precious resources to a few seasoned engineers. Let them, rather than bean counters, grapple with the vexing tradeoffs. They're used to minimizing risk, and know how to use limited means to achieve their goals. They favor the conservation of the best and proven elements of a strategy, and are lured into deviation only after all the worst-case consequences of a decision have been evaluated."
Looking back on his work, Gilbert says "There are no algorithms for success. All things worth doing must be semi-hard." He believes an insatiable curiosity, the gift of a strong work ethic (perhaps even a little poverty when young), the serendipity of opportunity, and early recognition are matters of chance. He accepts credit only as a response to those gifts and opportunities, for leveraging curiosity to access insights, and for being prepared to earn recognition based solely on results.
"In IC development, one must be willing to work with consistency and determination over long time-spans," he says. "However, if you can't distinguish between play and what you are being paid to do, the notion of work becomes blurred. I've been fortunate in enjoying a modicum of success as a spin-off from the sheer pleasure of tinkering with a few transistors." His ICs, he notes, have generated an aggregate revenue of about $1 billion.
Consumed by all things electronic for some 60 years, Gilbert has no interest in retiring. "I'm energized by the opportunity of being creative in a very supportive company," he says, "and eagerly await the appearance of each day's new discovery. I hope to turn a lot more new ideas into useful products."