PNS-FCR: Flexible Charge Recycling Dynamic Circuit Technique for Low-Power Microprocessors

摘要

Due to the superior speed and area characteristics, dynamic circuits are widely applied in data paths and other time critical components in modern microprocessors. The high switching activity of dynamic circuits, however, consumes significant power. In this paper, a p-type-type dynamic circuit selection (PNS) algorithm and a flexible charge recycling (FCR) design methodology are proposed to achieve high power efficiency in data paths. The effects of technology scaling, data path width, design complexity, clock skew, and environmental conditions are discussed. Simulation results show that the power consumption of an arithmetic and logic unit (ALU) with the proposed PNS-FCR can be reduced by up to 60% as compared with a conventional ALU. An 8-bit ALU test circuit has also been manufactured based on a 0.35- Global Foundries technology, demonstrating the power and area efficiency of the proposed methodology.