Our purpose in writing this book was two-fold. First, we wanted to compile a chronology of the research in the field of mixed-mode simulation over the last ten to fifteen years. A substantial amount of work was done during this period of time but most of it was published in archival form in Masters theses and Ph. D. dissertations. Since the interest in mixed-mode simulation is growing, and a thorough review of the state-of-the-art in the area was not readily available, we thought it appropriate to publish the information in the form of a book. Secondly, we wanted to provide enough information to the reader so that a proto­ type mixed-mode simulator could be developed using the algorithms in this book. The SPLICE family of programs is based on the algorithms and techniques described in this book and so it can also serve as docu­ mentation for these programs. ACKNOWLEDGEMENTS The authors would like to dedicate this book to Prof. D. O. Peder­ son for inspiring this research work and for providing many years of support and encouragement The authors enjoyed many fruitful discus­ sions and collaborations with Jim Kleckner, Young Kim, Alberto Sangiovanni-Vincentelli, and Jacob White, and we thank them for their contributions. We also thank the countless others who participated in the research work and read early versions of this book. Lillian Beck provided many useful suggestions to improve the manuscript. Yun­ cheng Ju did the artwork for the illustrations.

Inhalt

1. Introduction to Mixed-Mode Simulation.- 1.1 The Simulation Problem.- 1.2 Levels of Simulation.- 1.2.1 Electrical Simulation.- 1.2.2 Gate-Level Simulation.- 1.2.3 Switch-Level Simulation.- 1.2.4 Register-Transfer Level Simulation.- 1.2.5 Behavioral Level Simulation.- 1.3 Mixed-Mode Simulation.- 1.3.1 Basic Issues in Mixed-Mode Simulation.- 1.3.2 A Survey of Existing Simulators.- 1.4 Outline of Book.- 2. Electrical Simulation Techniques.- 2.1 Equation Formulation.- 2.2 Standard Techniques for Transient Analysis.- 2.3 Time-Step Control: Theoretical Issues.- 2.3.1 Constraints on Step Size.- 2.3.2 Solution of Nonlinear Equations.- 2.4 Time-Step Control: Implementation Issues.- 2.4.1 LTE Time-Step Control.- 2.4.2 Iteration Count Time-Step Control.- 3. Relaxation-Based Simulation Techniques.- 3.1 Latency and Multirate Behavior.- 3.2 Overview of Relaxation Methods.- 3.2.1 Linear Relaxation.- 3.2.2 Nonlinear Relaxation.- 3.2.3 Waveform Relaxation.- 3.2.4 Partitioning for Relaxation Methods.- 4. Iterated Timing Analysis.- 4.1 Equation Flow for Nonlinear Relaxation.- 4.2 Timing Analysis Algorithms.- 4.3 Splice 1.7 - Fixed Time-Step ITA.- 4.4 iSplice3.1 - Global-Variable Time-Step ITA.- 4.4.1 Circuit Partitioning.- 4.4.2 Global-Variable Time-Step Control.- 4.5 Electrical Events and Event Scheduling.- 4.5.1 Latency Detection.- 4.5.2 Events and Event Scheduling.- 4.5.3 Latency in the Iteration Domain.- 5. Gate-Level Simulation.- 5.1 Introduction.- 5.2 Evolution of Logic States.- 5.2.1 Two-State Logic Model.- 5.2.2 Ternary Logic Model.- 5.2.3 A Four-State Logic Model.- 5.2.4 A Nine-State Logic Model.- 5.3 Characterization of Switching Properties.- 5.4 Logic Switching Delay Models.- 5.5 Logic Simulation Algorithm.- 6. Switch-Level Timing Simulation.- 6.1 Introduction.- 6.2 Switch-Level Simulation.- 6.3 A Generalization of the Nine-State Logic Model.- 6.4 Simulation Using the Generalized Model.- 6.4.1 Electrical-Logic Simulation.- 6.4.2 The Elogic Algorithm.- 6.4.3 Problems with the Elogic Approach.- 6.5 A Survey of Switch-Level Timing Simulators.- 6.6 The Mixed-Mode Interface.- 7. Implementation of Mixed-Mode Simulation.- 7.1 Simulator Architecture.- 7.2 Event Scheduler Design.- 7.2.1 Linear Linked-List Structure.- 7.2.2 Indexed List Methods.- 7.2.3 Classical Time-Wheel.- 7.2.4 Managing Remote Lists.- 7.2.5 Other General Scheduling Issues.- 7.3 Transient Analysis and Event Scheduling.- 7.4 DC Analysis techniques.- 7.5 Mixed-Mode Simulation Examples.- 8. Conclusions and Future Work.- 8.1 Summary.- 8.2 Areas of Future Work.- 8.2.1 Automatic Partitioning.- 8.2.2 Fault Simulation.- 8.2.3 Analog Multilevel Simulation.- 8.3 Conclusions.- References.- About the Authors.