Accurate and E cient Technique to CalculateSensitivities of Power to Uncertainties in

Recently, several power estimation techniques have been proposed. Some of them can be used to accurately estimate power dissipation provided that the exact signal probability (probability of a signal being logic ONE) and signal activity (probability of signal switching) of primary inputs are known. In general, very accurate speciication of primary input signal probability and activity may not be available. This in turn may result in uncertainties in average power estimation. In this paper we present a novel and eecient technique to estimate the sensitivity of average power dissipation to input signals using a symbolic estimation technique. Results for benchmark circuits show that power sensitivities can vary widely for diierent primary inputs of a circuit. Hence, in order to accurately estimate average power dissipation, the sensitive inputs of a circuit have to be speciied accurately. We have also developed a Monte-Carlo based technique to estimate power sensitivity which also acts as a gure of merit for the symbolic technique.