U. Glaeser

FIGURE 20.12 Probabilistic and statistical run-time.
FIGURE 20.13 Probabilistic and statistical total power consumption.
Comparing Probabilistic with Statistical Results
Figure 20.11 illustrates the percentage total power consumption due to internal nodes as obtained from
both probabilistic and statistical techniques [15]. A dashed line and a solid line for statistical and probabilistic
techniques represent the results, respectively. On an average, the result from the statistical technique is
slightly lower than the result obtained from the probabilistic approach. The discrepancy arises from
various different sets of simplifying assumptions used in both techniques. Nevertheless, both results track
one another closely.
Figure 20.12 illustrates the run time of the probabilistic and statistical techniques [15]. The vertical
axis is in log scale. The probabilistic technique, as expected, runs one or two magnitude order faster than
the statistical technique. The statistical technique needs a number of simulation runs before the result
© 2002 by CRC Press LLC
CPU time in seconds
Total power estimation measure
10 4
10 3
10 2
10 1
10 0
10 1
10 2
10 3
10 3
10 2
10 1
10 0
CPU time of Statistical (Dashed line) and Probabilistic (Solid line) techniques
C1355 C17 C1908 C2670 C3540 C432 C499 C5315 C6288 C7552 C880
Iscas benchmark circuits
10 4
Total power estimation of Statistical (Dashed line) and Probabilistic (Solid line) techniques
C1355 C17 C1908 C2670 C3540 C432 C499 C5315 C6288 C7552 C880
Iscas benchmark circuits