Circuit partitioning techniques for power estimation using the full set of input correlations

Exact power estimation, at logic level, is only possible if all the input correlations are taken into account. Recently, a probabilistic approach that uses a simple but powerful formalism for power estimation taking into account all the input correlations has been proposed. With this probabilistic approach it is possible to compute exactly the power dissipation of combinational modules using input statistics that would require extremely large traces if simulation based methods were to be used. However, the applicability of the method is limited to very small circuits. This paper describes a circuit partitioning technique that speeds up that method. By using partitioning techniques we avoid the computation of global BDD representations for node functions, thereby extending considerably the range of applicability of the algorithm. Moreover, the partitioning maintains the full set of correlations and, therefore, does not induce any loss of accuracy