Placement techniques for the physical synthesis of nanometer-scale integrated circuits

Abstract

Placement is a critical component in the physical synthesis of nanometer-scale integrated circuits. Placement of circuit modules determines to a large extent interconnect length and routing resource demand. Interconnect length has a direct impact on the interconnect delay, which has become the determining factor of circuit performance in nanometer-scale process technology. In addition, interconnect length has a direct impact on the circuit power. Hence, the quality of the placement significantly affects the ability of a physical synthesis tool or designer to achieve design closure. In this work, efficient and high quality placement techniques have been developed for the physical synthesis of multi-million gate integrated circuits in the nanometer regime. The focus of these techniques are: (a) global placement and legalization of mixed-size circuits to minimize interconnect length, circuit power and routing resource demand, and (b) incremental physical synthesis via integrated timing optimization and placement to achieve timing closure. The effectiveness of the techniques is demonstrated by: (a) comparing them with existing approaches that perform integrated circuit placement, and (b) embedding them within a stateof-the-art industrial physical synthesis tool that is used in the design of high performance integrated circuits in the 65nm and 45nm process technology nodes.