EECS 298-11: CAD Seminar
Wednesday, April 19, 5pm
531 Cory Hall, Hogan Room


          How Matrix-Free Iterative Methods Have Changed Computer 
            Simulation of Circuits, Devices, Interconnect, and 
                    Micro-Electro-Mechanical Systems

                             Prof. Jacob White
                                   MIT

Iterative matrix solution methods, like relaxation, have been used in computer
simulation programs for several decades and their use has greatly expanded in
the last several years.  This expanded use is primarily due to the development
of robustly converging Krylov-subspace methods for general nonsymmetric
problems, such as preconditioned GMRES and QMR. Perhaps surprisinglyf, the most
important practical aspect of using Krylov-subspace methods is not that they
are faster than direct factorization for well-conditioned problems.  What has
proven to be much more important is that Krylov-subspace methods only require
the ability to compute a matrix-vector product and do NOT require an explicit
representation of the matrix.  In this talk, we will show how this simple
"matrix-free" idea can be exploited to develop fast algorithms for periodic
steady-state analysis of large nonlinear circuits and parallel algorithms for
transient simulation of semiconductor devices.  We will then show how the
matrix-free idea can be combined with sparsification techniques to perform very
fast electromagnetic analysis of complex 3-D structures.  Finally, we will show
how the matrix-free idea can be used as a software engineering tool, by
demonstrating its use as a technique for coupling existing simulation programs
to perform coupled electromechanical simulation of micro-electro-mechanical
systems.

Future Seminars:

April 26 - Tom Parks, UC Berkeley
           "Dataflow Process Networks"

May 3    - Antun Domic, Cadence
           "Some problems in submicron technology and their effect on design 
            methods and CAD tools"

May 5    - Georges Gielen, KU-Leuven (Special seminar, Friday, 2PM)
           "Research Developments in Analog CAD at KU-Leuven"

May 10   - Stan Liao, MIT
           "Code Generation and Optimization for Embedded DSP Processors"

End of semester