Vector compaction for efficient simulation-based power estimation [CMOS design]

Low power digital CMOS circuit design requires accurate power estimation. To achieve the accuracy of dynamic power estimation and the speed of static estimation methods, one approach is to generate a compact, representative vector set with similar switching behaviour to the original larger vector set. In this paper, we present an algorithm based on fractal concepts to generate a compacted vector that allows fast, accurate power estimation through simulation. The fractal approach exploits the correlation in the toggle distribution of the circuit's internal nodes for compaction of the input vector set. Experiments on ISCAS85 benchmark circuits with a vector set size of 4000, resulted in a compaction of 65.57/spl times/ (max) and 38.14/spl times/ (avg) with power estimation error of 2.40% (max) and 2.06% (avg). Also, experiments with different vector set sizes up to 100,000 were also carried out.