Method and apparatus of estimating power dissipation and method and apparatus of determining layout/routing

摘要

This invention discloses a method of estimating power dissipation in an electrical circuit formed by a plurality of elements and a plurality of signal lines for input/output transfer. The probability that an output signal makes a transition in response to a change in an input signal is found. Based on this, a formula is found which expresses the output signal transition probability as a function of the input signal transition probability. This method has the following steps. An input signal transition probability is given. By making use of the formula, an output signal transition probability is found in relation to an input signal having the given signal transition probability. Estimation of power dissipation is performed by summing products obtained by multiplying each transition probability by each signal line's load. Computation of the signal transition probability starts at the input side. As a result of such arrangement, power dissipation can be estimated from each signal transition probability.