The Study Of Signal Integrity By FDTD

With the development of high-speed digital circuit and high-density chip technology, the electromagnetic compatible (EMC) question is more and more focused. But in fact, the signal frequency of system is more and more high, The analysis of time domain response of multi-conductor 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. In the design of high-speed circuit, some question such as delay, reflection, attenuation, scattering, crosstalk, ground bounce etc will result in prominent signal pulse distortion, even though signal transmit a little distance. Previous circuit-analysis technique is using software, the limitations of such an approach are that his bandwidth is too narrow to meet demand. But the using finite-difference time-domain (FDTD) can obtain all of time domain response only through once simulation, which have more accuracy. So this method have significant in interconnect design.Firstly, this paper introduces the basis theories of FDTD, and then introduces some pivotal technology in making electromagnetic modeling. Followed this, through analyzing the signal integrity of classical theories, presents an new approach of analyzing crosstalk of multi-conductor transmission lines by FDTD. Finally, basing on anterior theories, the crosstalk is given which parallel microstrip and non-parallel microstrip, without via hole, with via hole, and with via tops connected by metal strip. By comparing with other literature, the programs are validate and results are correct, which are helpful to study the more complex interconnect and packaging further.