A probabilistic approach for RT-level power modeling

We propose a method for register-transfer level (RTL) power modeling. The switched capacitance and switching probability of each output of a functional module are modeled by formulas that are a function of the module's inputs probabilities. These formulas are computed beforehand for each module using the polynomial simulation scheme, and stored in the module library. The switched capacitance (and thus power) for each instance of a module in the circuit can then be efficiently evaluated for its specific input probabilities. The switching probabilities at the outputs of each module can be computed in a similar manner, thus providing a means of propagating the switching probabilities through the circuit described at the RT level. We provide a set of experimental results that show that this method provides estimates close to the logic-level estimates, but is orders of magnitude faster.