Demonstration of Speed and Power Enhancements on an Industrial Circuit Through Application of Clock Skew Scheduling

A strategy to enhance the speed and power characteristics of an industrial circuit is demonstrated in this paper. It is shown that nonzero clock skew scheduling can improve circuit performance while relaxing the strict timing constraints of the critical data paths within a high speed system. A software tool implementing a nonzero clock skew scheduling algorithm is described together with a methodology that generates the required clock signal delays. Furthermore, a technique that significantly reduces the power dissipated in the noncritical data paths is demonstrated. The application of this technique combined with nonzero clock skew scheduling to the slower data paths is also described. Speed improvements of up to 18% and power savings greater than 80% are achieved in certain functional blocks of an industrial high performance microprocessor.

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