This book is the first in a series of three dedicated to advanced topics in Mixed-Signal IC design methodologies. It is one of the results achieved by the Mixed-Signal Design Cluster, an initiative launched in 1998 as part of the TARDIS project, funded by the European Commission within the ESPRIT-IV Framework. This initiative aims to promote the development of new design and test methodologies for Mixed-Signal ICs, and to accelerate their adoption by industrial users. As Microelectronics evolves, Mixed-Signal techniques are gaining a significant importance due to the wide spread of applications where an analog front-end is needed to drive a complex digital-processing subsystem. In this sense, Analog and Mixed-Signal circuits are recognized as a bottleneck for the market acceptance of Systems-On-Chip, because of the inherent difficulties involved in the design and test of these circuits. Specially, problems arising from the use of a common substrate for analog and digital components are a main limiting factor.