Asymptotic Waveform Evaluation (AWE) has been demonstrated as an efficient approach for interconnect circuit simulation/analysis. However, since it is based upon moment-matching, it is prone to yielding unstable approximations for stable circuits. This paper describes a systematic approach for alleviating the inherent instability associated with AWE and moment-matching methods as they apply to passive, digital, interconnect circuits. The efficiency and accuracy of this approach are demonstrated on several large, RLC interconnect-circuit problems.>

This paper presents a method of obtaining time-domain macromodels of VLSI interconnection networks for circuit simulation. The goal of this work is to include interconnect parasitics in a circuit simulation as efficiently as possible, without significantly compromising accuracy. Stability issues and enhancements to incorporate transmission line interconnects are also discussed. A unified circuit simulation framework, incorporating different classes of interconnects and based on the proposed macromodels, is described. The simplicity and generality of the macromodels is demonstrated through examples employing RC- and RLC-interconnects.>

The results of linear asymptotic waveform evaluation (AWE) and of nonlinear circuit simulation are combined for the purpose of efficiently incorporating accurate interconnect information in the overall circuit description. A simple macromodel based on the y-parameter description of a complex interconnect network is discussed. The model makes possible the reduction of large, stiff interconnect configurations into compact representations that pose minimal problems to conventional circuit simulation techniques. The macromodel can be incorporated directly into a conventional circuit simulation with no modification of the original simulation software. The techniques are suitable for development as a software library that can be used to enhance existing simulators so that they can handle large VLSI interconnect configurations very efficiently. In addition, the ability to handle elements at the port level makes approach extremely attractive for any linear(ized) macromodels or for application such as mixed-mode simulation.>

The authors derive, implement, and demonstrate a computational approach for the measurement of emergent image frequencies. Measuring emergent signal frequencies requires spectral measurements accurate in both frequency and time or space, conflicting requirements that are shown to be balanced by a generalized uncertainty relationship. Such spectral measurements can be obtained from the responses of multiple wavelet-like channel filters that sample the signal spectrum, and that yield a locus of possible solutions for each locally emergent frequency. It is shown analytically that this locus of solutions is maximally localized in both space and frequency if the channel filters used are Gabor wavelets. A constrained solution is obtained by imposing a stabilizing term that develops naturally from the assumptions on the signal. The measurement of frequencies is then cast as an ill-posed extremum problem regularized by the stabilizing term, leading to an iterative constraint propagation algorithm. The technique is demonstrated by application to a variety of 2-D textured images.>

Article RICE: Rapid interconnect circuit evaluator Share on Authors: Curtis L. Ratzlaff The University of Texas at Austin, Department of Electrical and Computer Engineering, Austin, TX The University of Texas at Austin, Department of Electrical and Computer Engineering, Austin, TXView Profile , Nanda Gopal The University of Texas at Austin, Department of Electrical and Computer Engineering, Austin, TX The University of Texas at Austin, Department of Electrical and Computer Engineering, Austin, TXView Profile , Lawrence T. Pillage The University of Texas at Austin, Department of Electrical and Computer Engineering, Austin, TX The University of Texas at Austin, Department of Electrical and Computer Engineering, Austin, TXView Profile Authors Info & Claims DAC '91: Proceedings of the 28th ACM/IEEE Design Automation ConferenceJune 1991 Pages 555–560https://doi.org/10.1145/127601.127732Online:01 June 1991Publication History 127citation652DownloadsMetricsTotal Citations127Total Downloads652Last 12 Months7Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access

The authors describes a relation for specifying the 'optimal' number of lumped RC sections needed to approximate a distributed RC element for an estimated digital-signal bandwidth. The bandwidth approximation also aids in determining the order of the AWE (asymptotic waveform evaluation) approximation for the driving-point and transfer function models. Since moving to arbitrarily high orders of approximation to meet the bandwidth requirements is complicated by moment-matching instability problems, a constrained mapping from moments to dominant time constants is used which guarantees stability for RC interconnect models.>

The efficacy of the 2-D Gabor channel filters for segmenting images based on the division of the image into textures was established previously. In the present work, the authors extend the model for the direct estimation of the emergent spatially localized orientation/frequencies of visible patterns using a variational scheme. The most significant result of this extension is that patterns with space-varying frequency characteristics, arising from, e.g. surface deformation, can still be analyzed and segregated. Moreover, the information extracted can provide a means for developing shape-from-texture algorithms that are optimally localized. The implementation of the filtering scheme is described.>