The high-speed electrical characteristics of a typical multilayerceramic (MLC) package are described and a model presented. The testswere conducted in a realistic environment which closely models thesurface mount environment for which the packages are intended. These MLCpackages incorporate many of the same refinements used at thecircuit-board level to improve high-speed performance, namely use ofcontrolled impedance, 50 Ω, signal lines, multiple groundconnections, and on-package power and ground planes. Using pulsereflection and transmission measurements as a diagnostic tool, it isshown how to develop a full SPICE model for a high-speed MLC package ina systems environment. A dominant electrical feature of theconfiguration is the ground plane discontinuity at thepackage-to-circuit board interface. This feature is prominent in theobserved high-speed pulse response of the system
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