Analog integrated circuits are very important as interfaces between the digital parts of integrated electronic systems and the outside world. A large portion of the effort involved in designing these circuits is spent in the layout phase. Whereas the physical design of digital circuits is automated to a large extent, the layout of analog circuits is still a manual, time-consuming and error-prone task. This is mainly due to the continuous nature of analog signals, which causes analog circuit performance to be very sensitive to layout parasitics. The parasitic elements associated with interconnect wires cause loading and coupling effects that degrade the frequency behaviour and the noise performance of analog circuits. Device mismatch and thermal effects put a fundamental limit on the achievable accuracy of circuits. For successful automation of analog layout, advanced place and route tools that can handle these critical parasitics are required. In the past, automatic analog layout tools tried to optimize the layout without quantifying the performance degradation introduced by layout parasitics. Therefore, it was not guaranteed that the resulting layout met the specifications and one or more layout iterations could be needed. In Analog Layout Generation for Performance and Manufacturability, the authors propose a performance driven layout strategy to overcome this problem. In this methodology, the layout tools are driven by performance constraints, such that the final layout, with parasitic effects, still satisfies the specifications of the circuit. The performance degradation associated with an intermediate layout solution is evaluated at runtime using predetermined sensitivities. In contrast with other performance driven layout methodologies, the tools proposed in this book operate directly on the performance constraints, without an intermediate parasitic constraint generation step. This approach makes a complete and sensible trade-off between the different layout alternatives possible at runtime and therefore eliminates the possible feedback route between constraint derivation, placement and layout extraction. Besides its influence on the performance, layout also has a profound impact on the yield and testability of an analog circuit. In Analog Layout Generation for Performance and Manufacturability, the authors outline a new criterion to quantify the detectability of a fault and combine this with a yield model to evaluate the testability of an integrated circuit layout. They then integrate this technique with their performance driven routing algorithm to produce layouts that have optimal manufacturability while still meeting their performance specifications. Analog Layout Generation for Performance and Manufacturability will be of interest to analog engineers, researchers and students.

In the past two decades, research in VLSI physical design has been directed toward automation of layout process. Since the cost of fabricating a circuit is a fast growing function of the circuit area, circuit layout techniques are developed with an aim to produce layouts with small areas. Other criteria of optimality such as delay and via minimization need to be taken into consideration. This book includes 14 articles that deal with various stages of the VLSI layout problem. It covers topics including partitioning, floorplanning, placement, global routing, detailed routing and layout verification. Some of the chapters are review articles, giving the state-of-the-art of the problems related to timing driven placement, global and detailed routing, and circuit partitioning. The rest of the book contains research articles, giving recent findings of new approaches to the above-mentioned problems. They are all written by leading experts in the field. This book will serve as good references for both researchers and professionals who work in this field.

Design and optimization of integrated circuits are essential to the creation of new semiconductor chips, and physical optimizations are becoming more prominent as a result of semiconductor scaling. Modern chip design has become so complex that it is largely performed by specialized software, which is frequently updated to address advances in semiconductor technologies and increased problem complexities. A user of such software needs a high-level understanding of the underlying mathematical models and algorithms. On the other hand, a developer of such software must have a keen understanding of computer science aspects, including algorithmic performance bottlenecks and how various algorithms operate and interact. "VLSI Physical Design: From Graph Partitioning to Timing Closure" introduces and compares algorithms that are used during the physical design phase of integrated-circuit design, wherein a geometric chip layout is produced starting from an abstract circuit design. The emphasis is on essential and fundamental techniques, ranging from hypergraph partitioning and circuit placement to timing closure.

Moore's law [Noy77], which predicted that the number of devices in tegrated on a chip would be doubled every two years, was accurate for a number of years. Only recently has the level of integration be gun to slow down somewhat due to the physical limits of integration technology. Advances in silicon technology have allowed Ie design ers to integrate more than a few million transistors on a chip; even a whole system of moderate complexity can now be implemented on a single chip. To keep pace with the increasing complexity in very large scale integrated (VLSI) circuits, the productivity of chip designers would have to increase at the same rate as the level of integration. Without such an increase in productivity, the design of complex systems might not be achievable within a reasonable time-frame. The rapidly increasing complexity of VLSI circuits has made de- 1 2 INTRODUCTION sign automation an absolute necessity, since the required increase in productivity can only be accomplished with the use of sophisticated design tools. Such tools also enable designers to perform trade-off analyses of different logic implementations and to make well-informed design decisions.

The physical design flow of any project depends upon the size of the design, the technology, the number of designers, the clock frequency, and the time to do the design. As technology advances and design-styles change, physical design flows are constantly reinvented as traditional phases are removed and new ones are added to accommodate changes in technology. Handbook of Algorithms for Physical Design Automation provides a detailed overview of VLSI physical design automation, emphasizing state-of-the-art techniques, trends and improvements that have emerged during the previous decade. After a brief introduction to the modern physical design problem, basic algorithmic techniques, and partitioning, the book discusses significant advances in floorplanning representations and describes recent formulations of the floorplanning problem. The text also addresses issues of placement, net layout and optimization, routing multiple signal nets, manufacturability, physical synthesis, special nets, and designing for specialized technologies. It includes a personal perspective from Ralph Otten as he looks back on the major technical milestones in the history of physical design automation. Although several books on this topic are currently available, most are either too broad or out of date. Alternatively, proceedings and journal articles are valuable resources for researchers in this area, but the material is widely dispersed in the literature. This handbook pulls together a broad variety of perspectives on the most challenging problems in the field, and focuses on emerging problems and research results.

This title covers important physical-design issues that exist in contemporary analogue and mixed-signal design flows. The authors bring together many principles and techniques required to successfully develop and implement layout generation tools to accommodate many mixed-signal layout generation needs.