In this paper we investigate activity-driven clock trees to reduce the dynamic power consumption of synchronous digital CMOS circuits. Sections of an activity-driven clock tree can be turned on/o by gatingthe clock signals duringthe active/idle times of the clocked elements. We propose a method of obtaining the switching activity patterns of the clocked circuits during the high level design process. We formulate three novel activity-driven problems. The objective of these problems is to minimize system's dynamic power consumption. We propose an approximation algorithm based on recursive matching to solve the clock tree construction problem. We solve the gate insertion problems with an exact algorithm employing the dynamic programming paradigm. Finally, we present experimental results that verify the eectiveness of our approach. Our work in this paper is a step in understanding how high level decisions (e.g. behavioral design) can aect a low level design (e.g. clock design).
Gustavo E. Téllez, Amir H. Farrahi, Majid S