Introduction

Although nowadays most application-specific integrated circuits (ASICs) are designed fully or partially based on a specific synthesis flow using hardware description languages (HDLs) and implemented by either field-programmable gate arrays (FPGAs) or cell libraries, it is increasingly important to understand the fundamentals of circuit and physical designs of very large-scale integration (VLSI) circuits at least due to the following reasons. First, addressing the harder problems requires fundamental understanding of circuit and physical design issues. Second, distinguished engineers can often develop their physical intuition to estimate the behavior of circuits rapidly without relying on computer-aided design (CAD) tools predominantly.