where General RLC circuits can be modeled in the following form where the state vector x(t) comprises of the node voltages and branch currents necessary for circuit analysis. If the circuit is of the regular tree structure as shown in Fig 1, then the system matrices E, A and F in equation 1 would be of special structure, which simplifies the moment computation .Circuit moment is a concept derived from the expansion of the frequency response H (s) of a linear network in a series of s, for example in Section III. Application of SMC in statistical timing analysis is shown in Section IV. Conclusions are made in Section V is called the ith moment of the impulse response h(t) for i = 0,1 ,2, ' . '. Here for convenience we have defined all moments to be nonnegative. Moments are useful in that they can be used for constructing reduced order models with the constraint of matching low-order moments [1] [7].