Events Calendar

Munushian Seminar

Speaker: Dr. Barrie Gilbert, Fellow, Analog Devices Inc.

Talk Title: THE PENNY ANALOG COMPUTER

Abstract: Seventy years ago, analog computers were at the peak of their history. Today, it is commonly said that “analog computing is a dead art”. But the truth is that the core principles are still very much alive in a broad range of modern analog integrated circuits. Function generation, equation solving, correlation, power measurement – at frequencies ranging from sub-sonic seismic to 50 GHz – and the extraction of signal statistics – to mention just a few of such operations – are now in use in numerous IC products. Yet these ICs are tiny and truly inexpensive: many sell for not very many pennies, at as discrete-functions; some specialized nonlinear continuous-time and continuous amplitude processors – truly micro-miniature analog computers – may even represent less than one US penny in the overall cost of a large-scale IC.
This talk is in two parts. The first traces some of the vast history of “continuous-time computers using corresponding analogies”, especially those made during WW-2 years. They were often huge, filling large rooms, weighing tons, and consuming great amounts of power. Programming was tedious in the extreme, and their accuracy was not impressive. But during this passage, we quickly gravitate to the key principles of modern analog microcomputers, which are heavily reliant on the remarkable logarthmic/exponential properties of monolithic bipolar transistors.
The second part expands further on some seminal concepts, comprising the domain called “Translinear” design, in the hope of clearly illustrating not just the potency of the bipolar transistor in these roles, but also to demonstrate the elegant simplicity of the core cells. Several case studies of recent “penny-level analog computers” with significant capabilities will be presented.

Biography: Biography:Barrie Gilbert is the legendary circuit designer credited with the BJT translinear principle, which led to the development of the precision analog multiplier and numerous other circuits such as wide-range variable gain amplifiers. He has been involved with designing circuits from the days of electron tubes to present day high performance IC's, and many of his chip designs have remained in mass production for over 30 years. His original paper on the four-quadrant analog multiplier is the 5th most frequently cited in the history of the IEEE Journal of Solid-State Circuits.

Barrie has received an honorary doctorate from Oregon State University, and was elected Analog Devices Fellow, Life Fellow of the IEEE, and Member of the National Academy of Engineering.


Host: EE-Electrophysics

More Info: ee.usc.edu/news/munushian

Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248

Audiences: Everyone Is Invited

Contact: Marilyn Poplawski

Event Link: ee.usc.edu/news/munushian