DEPACT: delay extraction-based passive compact transmission-line macromodeling algorithm

Abstract

With the continually increasing operating frequencies, signal integrity and interconnect analysis in high-speed designs is becoming increasingly important. Recently, several algorithms were proposed for macromodeling and transient analysis of distributed transmission line interconnect networks. The techniques such as method-of-characteristics (MoC) yield fast transient results for long delay lines. However, they do not guarantee the passivity of the macromodel. It has been demonstrated that preserving passivity of the macromodel is essential to guarantee a stable global transient simulation. On the other hand, methods such as matrix rational approximation (MRA) provide efficient macromodels for lossy coupled lines, while preserving the passivity. However, for long lossy delay lines this may require higher order approximations, making the macromodel inefficient. To address the above difficulties, this paper presents a new algorithm for passive and compact macromodeling of distributed transmission lines. The proposed method employs delay extraction prior to approximating the exponential stamp to generate compact macromodels, while ensuring the passivity. Validity and efficiency of the proposed algorithm is demonstrated using several benchmark examples.Index Terms-Circuit simulation, delay extraction, distributed interconnects, high-speed modules, matrix rational approximation (MRA), method of characteristics (MoC), multiconductor transmission lines, passive macromodels, printed circuit boards, transient analysis.

Fast transient analysis method for lossy nonuniform transmission line with nonlinear terminations

“…However, it need higher order approximations for the long lossy delay lines [5]. A passive delay extraction-based macromodeling algorithm (DEPACT) has been introduced for simulation of long lossy uniform lines [11,12]. But the macromodeling of the lossy nonuniform transmission lines have not been reported.…”

“…The exponential term can be approximated using the DEPACT. In the process of building the macromodels of the lossy uniform transmissions, the per-unit-length parameter matrices will be changed with the approximated order in [11]. In this paper, we improved the approximated equation as…”

Model Order Reduction for Neutral Systems by Moment Matching

“…However, direct simulation of the original high or even infinite order models is very difficult and sometimes prohibitive due to unmanageable levels of storage, high computational cost and long computation time. Therefore, model order reduction (MOR) , which replaces the original complex and high-order system by a reduced-order model (ROM), plays an important role in many areas of engineering, e.g., transmission lines in circuit packaging [31,38], PCB (printed circuit board) design [11,48,58] and networked control systems [18,28]. The obvious advantages of MOR include that the use of ROMs results in not only considerable savings in storage and computational time, but also fast simulation and verification leading to shortened design cycle [2,3,5,12,15,26,33,34,36,52,59].…”

Parameterized macromodels of multiconductor transmission lines

“…The accurate and efficient prediction of these effects is crucial for a successful design. Over the years, several different techniques have been proposed for the analysis of multiconductor transmission lines [1]- [3].…”