High Speed Integrated Circuit Interconnect Delay Analysis

With the rapid increase of signal frequency and decrease of feature sizes in high speed integrated circuit (IC) systems, interconnects play increasingly important roles, and the analysis of the time-domain response of interconnects becomes necessary to ensure the circuit designed working properly. In the last decades, the work speed and the degree of integrating of VLSI increase continuously, which makes the request in the precision and efficiency of the analysis of the time-domain response of interconnects very high, and conventional software of circuit simulation can't do this work well. So much work has been done in the analysis of the time-domain response of interconnects. Interconnects between chips are simulated by regarding them as networks of transmission lines. Usually, the method of simulating is making time-domain model or frequency-domain model of transmission lines and then getting the response of time-domain, from which two methods of analyzing networks of transmission lines are gotten-the time-domain method and the frequency-domain method. The ABCD matrix of transmission lines is obtained by the Runge-Kutta iteration in this paper, then the ABCD matrix is used to obtain the solution in the Laplace-domain, finally the time-domain response is obtained through the numerical inversion of the Laplace transform, so that the traditional NILT method is able to analyze the nonuniform transmission lines, at the same time, it is efficient and accurate.