A new and efficient combination of signal tracing and block recognition techniques for circuit analysis is proposed. It utilizes the benefits of both approaches to solve problems such as signal flow or gate recognition. The analysis process is easily controlled by a user definable rule set where ports, nets and block are attributed with types. After structural investigation a hierarchical netlist is produced providing block information as subcircuits. As an important feature, the algorithm allows the handling of optional ports as well. Thus, this flexible approach is applicable to various circuit types and works on several abstraction levels.

The aim of this paper is to show that the multigrid approach can provide an efficient two-dimensional Poisson solver used in the analysis of realistic semiconductor devices based on particle simulators. Our robust implementation of the multigrid method is faster by one or two orders of magnitude than standard successive over-relaxation solvers and is capable, at the same time, of efficiently handling highly inhomogeneous grids and irregular boundary conditions relevant for realistic devices. All essential parts of the algorithm, such as coarsening, prolongation, restriction, and relaxation, have been adapted and optimized to deal with these complex geometries and large variations in the charge density. In particular, a new variant of the Gauss-Seidel-type relaxation scheme is introduced that is particularly suited for grids that lack globally dominant directions. As an example, the multigrid Poisson solver has been applied to two different electronic devices, a GaAs High Electron Mobility Transistor and a Si Metal Oxide Semiconductor Field Effect Transistor.