Passive interconnect reduction algorithm for distributed/measured networks

This paper presents an efficient algorithm for transient simulation of multiport distributed interconnect networks in the presence of nonlinear subcircuits. The proposed multilevel multipoint model-reduction algorithm combines the merits of recently proposed Krylov-space techniques and block complex frequency-hopping to generate compact time-domain macromodels. The method overcomes the difficulty of slower transient simulation caused by redundant poles in reduced-order models obtained by Krylov-space methods. Also, it provides an efficient means to translate Krylov-space-based reduced models of distributed/measured networks with frequency-dependent descriptions into time-domain macromodels. In addition, a strategy to preserve the passivity of macromodels during multilevel reduction is presented. An important advantage of the proposed algorithm is that it can directly handle distributed stamps such as transmission lines described by Telegrapher's equations, frequency-dependent parameters, full-wave, and measured subnetworks

A CAD Framework for Simulation and Optimization of High-Speed VLSI Interconnections

As signal speeds increase, interconnect effects such as signal delay, distortion, and crosstalk become the dominant factor limiting over all performance of VLSI systems. This paper describes a CAD framework addressing three specific aspects of the high-speed interconnect problem; namely, simulation, sensitivity analysis, and performance optimization. Distributed interconnect models represented by uniform or nonuniform lossy coupled transmission lines are supported. The CAD framework incorporates parallel processing capability. It also provides a design environment for integrating accurate simulations or waveform estimation, sensitivity analysis, design specifications, and numerical optimization. New approaches enhancing the accuracy and ensuring the stability of moment-matching techniques used in the asymptotic waveform evaluation (AWE) are introduced. Also described are a parallel implementation of numerical inversion of Laplace transform (NILT) and parallel interconnect optimization, resulting in substantial CPU speedup over existing NILT simulation and optimization

Integrating subnetworks characterized by measured data into moment-matching simulations

Moment-matching techniques have been proposed for efficient transient waveform estimation of interconnect networks used in modelling MCM's. In this paper, we introduce an approach for incorporating components characterized by measured data, within a moment matching simulation. The new method is applied using Complex Frequency Hopping (CFH), a multipoint moment-matching technique which enables the characterization of the network up to the highest frequency of interest. It allows for the efficient analysis of large networks which include lossy, coupled transmission lines, nonlinear terminations and arbitrary components represented by simulated or measured data