The Application Of The Fdtd-spice Technology High-speed Interconnect Structure Time-domain Analysis

With the development of semiconductor devices and electronic information technology, the density and speed of high speed VLSI is growing up with its function growing. The speed of the signal pulse is going faster. The analysis of time domain response of multiconductor transmission lines which used as interconnection line in VLSI is becoming a basic link to ensure good performance of the high speed electronic information system. Previous circuit-analysis technique makes their electromagnetic modeling firstly, and then extracts their equivalent circuit parameters, finally, the paraments were inputed to a general circuit simulator to be simulated. Limitations of such an approach in today's high frequencies and high speed circuitry of largescale integration is: i) the need of accurate parameter-extraction procedures for active device, and ii) the inadequacy of the equivalent-circuit representation for high-frequency interconnecting networks. Hence a new approach was brought forward in this paper: The analysis of time domain response of interconnecting and packaging structures using FDTD-SPICE. By this means, the extraction of equivalent circuit parameters is not needed any more.In this paper finite-difference time-domain (FDTD) method are coupled with a general circuit simulator SPICE in the time domain based on the full-wave simulation of FDTD and Maxwell's curl equation. They are connected by a series of ports in analyzed structurs. This method can be used to deal with nonuniform and discontinuous structures conveniently. Cause that the circuit element is treated as a part of the whole full-wave electromagnetic simulation, the parameter-extraction of interconnecting networks are not needed any more.Full wave modeling of multiconductor transmission lines and extraction of their equivalent frequency-dependent characteristic impedance are presented. Using FDTD-SPICE, crosstalk, ground bounce, skin effect, et al ofen seen in signal integrity analysis are also simulated, And discussions are drawn.