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This paper presents a selective survey of finite difference time domain (FDTD)-based interconnects modeling for signal integrity analysis problems. In spite of 47 years of its existence, researchers have focused on FDTD method with further modifications and enhancements for the signal integrity analysis of interconnects over the past two decades only. Because of the remarkable amount of interconnect-based FDTD-related research activity, tracking the FDTD literature can be a tedious and challenging task. This survey presents some of the significant methods and approaches employed to analyze the developments achieved up to the present-day signal integrity related research. These methods are based on solving telegrapher's equations which represent the transmission line behavior of interconnects. Recent research concentrates on developing novel methods for accurate interconnect modeling, extraction of interconnect parameters and incorporation of more lumped elements into FDTD. In this paper an attempt has been made to compare and summarize some of the well-known FDTD-based methods, which were used in interconnect related research.

Aggressive miniaturization has led to severe performance and signal integrity issues in copper-based interconnects in the nanometric regime. As a consequence, development of a proper analytical model for such interconnects is extremely important. In this work, an ABCD parameter matrix-based model is presented for fast and accurate estimation of crosstalk delay and noise for identically coupled copper-based nanointerconnect systems. Using the proposed model, the crosstalk delay and noise are estimated in copper based nanointerconnects for intermediate and global interconnects at the future integrated circuit technology nodes of 21 and 15 nm, respectively. Proposed model has been compared with SPICE and it is found that this model is almost 100% accurate as SPICE with respect to both the crosstalk delay as well as noise. Moreover, this model is as much as ~ 63 and ~ 155 times faster, respectively. From the crosstalk delay and noise analysis of unrepeated interconnects, it is observed that both delay and noise contribution will increase in scaled technology nodes. The same trend is observed also for the repeated interconnects. Also more number of repeaters and higher repeater sizes will be needed for delay minimization as we scale deeper. So as far as crosstalk induced effects are concerned, the copper interconnects will face a huge challenge to overcome in nanometer technology nodes.

Automotive communication systems are complex distributed systems. The design of the electrical physical layer (EPL) is a challenging task. Many parameters affect the signal integrity on the analog bus and the combination of parameter variations can lead to effects (e.g., signal reflections) which degrade the signal and compromise the system reliability. Model-based simulations have been widely proposed as the solution for the design, testing and verification of FlexRay networks. This paper proposes a model-based framework for the design and evaluation of FlexRay communication systems. The framework includes the development of FlexRay system components, the design of different network topologies and the simulation and analysis of EPL. The proposed framework has been developed and possible applications have been figured out. Furthermore, the validation of the proposed approach has been addressed. The validation focuses on the accuracy of the simulations in representing the analog signal on the bus, as well as the accuracy in representing the network timing characteristics. The validation exhaustively explores the system design space, achieving a rigorous analysis of the approach reliability: simulations of 40 different network topologies and 1,264 frames have been evaluated, by comparing simulation results with hardware measurements. The results demonstrate that the proposed framework accurately represents the hardware behavior, and it can be an useful toll during the design and early verification of FlexRay communication networks. Due to the lack of a formal validation approach for the validation of the electrical physical layer, the validation is valuable for the FlexRay community.