Pulsed-Latch Utilization for Clock-Tree Power Optimization

• Published in: IEEE transactions on very large scale integration (VLSI) systems Vol. 22; no. 4; pp. 721 - 733
• Main Authors: Lin, Hong-Ting, Chuang, Yi-Lin, Yang, Zong-Han, Ho, Tsung-Yi
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Circuit design; Clock tree migration; Clocks; dynamic power reduction; Flip-flops; Migration; Optimization; pulse generator; pulsed latch; Trees; Utilization; Very large scale integration
• ISSN: 1063-8210; 1557-9999
• DOI: 10.1109/TVLSI.2013.2252211

Minimizing the size of a clock tree is known as an effective approach to reduce power dissipation in modern circuit designs. However, most existing power-aware clock-tree minimization algorithms optimize power on the basis of flip-flops alone, which may result in limited power savings. To achieve a power and timing tradeoff, this paper investigates the pulsed-latch utilization in a clock tree for further power savings. This is the first paper to propose a migration approach to efficiently construct a clock tree with both pulsed-latches and flip-flops. The proposed method is based on minimum-cost maximum-flow formulation to globally determine the tree topology, which maintains load balance and considers the wirelength between pulse generators and pulsed latches. Experimental results indicate that the proposed migration approach can improve the power consumption by 12% and 13% with 7% and 70% skew improvements on average compared with the most recent paper on the industrial circuits and ISPD-2010 benchmarks, respectively.