Summary and Short Outline:
OpAmp is the main analog building block for both the systems on discrete elements and systems on silicon.
The parameters of OpAmp often define and limit the overall system performance. CMOS technology provides an
opportunity to use more complex structural solutions and circuit techniques to improve OpAmp accuracy,
power/speed ratio, add new functional advantages, like low voltage supply operation capability or rail
to rail input without switching point, for negligible additional component cost. The circuit techniques that
will be demonstrated during this course were proven in design of leading industrial OpAmps.
These techniques are unified by a common structural design approach, based on the following principles:
- system analysis at the high level of abstraction using the graphic tolls like signal flow graphs, and generation
of the set of equivalent graph modifications,
- equivalent graph transformations to the form when every important parameter in the system or amplifier is controlled
by a dedicated feedback loop;
- stability of these loops is achieved without compensation capacitors, using one-stage (preferably current)
- system synthesis consists of implementation of the set of the gain structure modifications followed by
simulations based on available library of cells, and selection of the best circuit solutions.
The particular topics covered in this half-day course include:
- amplifier speed and correct number of the gain stages;
- gain boosting in single and two-stage OpAmp structures and elimination of gain erosion due
to the drain-body leakage in single-well process;
- design of rail-to-rail input stages:
NMOS/PMOS stages with stabilized transconductance,
PMOS stage with low-noise charge pump for the tail current source,
Using the low-Vt transistors to eliminate the switching point;
- CMR and PSR improvement:
design of high quality tail current source,
cascoding of the input pair,
class AB output stage design;
- slew rate boost techniques;
- overload recovery time improvement;
- design techniques for 0.9 V power supply;
- using advantages of modern processes implementing different types of transistors.
Vadim V. Ivanov
Dr. Vadim Ivanov has his MSEE in 1980 and Ph.D.in 1987, both from the Institute
of Electrical Engineering, St. Petersburg, Russia. He worked as the designer of electronic
systems and ASICs for naval navigation equipment from 1980 to 1991 in
St. Petersburg, and as the designer of mixed signal ASICs for sensors, GPS/GLONASS
receivers and motor control systems between 1991 and 1995. Dr. Ivanov joined Burr Brown
(presently Texas Instruments, Tucson) in 1996 as a senior member of technical staff, where he
is involved with the design of operational, instrumentation, power
amplifiers, references and switching and linear voltage regulators. Dr.
Ivanov has 25 US patents, with 10 more pending, on analog circuit techniques.
He is the author and coauthor of more than 30 technical papers and three
books: "Integrated Power Amplifiers" (Leningrad, Rumb, 1987), "Analog
System Design with ASICs" (Leningrad, Rumb, 1988), both in Russian, and
"Operational Amplifier Speed and Accuracy Improvement", Kluwer, 2004.
I. M. Filanovsky
I. M. Filanovsky (M'81-SM'90) was born in Kirov, USSR, in 1940. He received the M.Sc.
degree in 1962 and the Ph.D. degree in 1968, both in electrical engineering
from V. I. Ulianov (Lenin) Institute of Electrical Engineering, Leningrad, USSR.
In 1976, he joined the University of Alberta, Canada, where he is currently a Professor.
He has coauthored with V.V. Ivanov the book Operational amplifier speed and accuracy
improvement (Analog circuit design with structural methodology) (Kluwer Academic Publishers, 2004),
and contributed to four books, Sensor Technology and Devices, L. Ristic, Ed., (Norwell, MA: Artech
House, 1994), Analog VLSI: Signal and Information Processing, M. Ismail and T. Fiez, Eds, (New York:
Mc-Graw-Hill, 1994), The Circuits and Filters Handbook, W.-K. Chen, Ed., (Boca Raton, FL: CRC Press,
1995), and The Electronics Handbook, J. Whitaker, Ed., (Boca Raton, FL: CRC Press, 1996). He was also
a contributor to The Encyclopedia of Electrical and Electronic Engineering, J. Webster, Ed., (New York:
Wiley, 1999) and Comprehensive Dictionary of Electrical Engineering, P. A. Laplante, Ed., (Boca Raton,
FL: CRC Press, 1999). In addition, he is the author or coauthor of about 200 journal and conference
proceedings publications on circuit theory (theory of approximation, theory and technical applications
of oscillations, strongly nonlinear oscillations) and applied microelectronics (analog electronic
circuits, oscillators and multivibrators, signal-conditioning circuits for sensors). He has four
patents on electronic circuits.
Dr. I. M. Filanovsky is an Associated Editor of IEEE Transactions on Circuits and Systems, Part I.
He is a Professional Engineer registered with APEGGA, Alberta, Canada. In the past he was Co-chairman
and Technical Program Chairman of 33rd International Midwest Symposium on Circuits and Systems in Calgary,
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