Title :
How to make theoretically passive reduced-order models passive in practice
Author :
Bai, Zhaojun ; Feldmann, Peter ; Freund, Roland W.
Author_Institution :
Lucent Technol., Bell Labs., Murray Hill, NJ, USA
Abstract :
This paper demonstrates that, in general, implementations of circuit reduction methods can produce unstable and nonpassive models even when such outcomes are theoretically proven to be impossible. The reason for this apparent contradiction is the numeric roundoff inherent in any finite-precision computer implementation. This paper introduces a new variant of the symmetric, multiport, Pade via Lanczos algorithm (SyMPVL) that, even in practice, is guaranteed to produce stable and passive models for all the circuits characterized by pairs of symmetric, positive semidefinite matrices. The algorithm is based on a new band Lanczos process with coupled recurrences. A number of circuit examples are used to illustrate the results
Keywords :
RC circuits; VLSI; circuit simulation; integrated circuit design; integrated circuit interconnections; integrated circuit modelling; reduced order systems; time-domain analysis; IC design; Lanczos process; VLSI; circuit reduction methods; coupled recurrences; finite-precision computer implementation; numeric roundoff; positive semidefinite matrices; reduced-order models; symmetric multiport Pade via Lanczos algorithm; Circuit simulation; Circuit stability; Coupling circuits; Data mining; Integrated circuit interconnections; RLC circuits; Reduced order systems; Symmetric matrices; Time domain analysis; Very large scale integration;
Conference_Titel :
Custom Integrated Circuits Conference, 1998. Proceedings of the IEEE 1998
Conference_Location :
Santa Clara, CA
Print_ISBN :
0-7803-4292-5
DOI :
10.1109/CICC.1998.694964