Error bound for reduced system model by Pade approximation via the Lanczos process

Recently, there has been a great deal of interest in using the Pade Via Lanczos (PVL) technique to analyze the transfer functions and impulse responses of large-scale linear circuits. In this paper, a matrix-based derivation of the error between the original circuit transfer function and the reduced-order transfer function generated using the PVL technique is presented. This error measure may be used for the development of an automated termination of the Lanczos process in the PVL technique and achieve the desired accuracy of the approximate transfer function. PVL coupled with such an error bound will be referred to as the PVL-WEB algorithm.