The Analysis Of Power Distribution Network And Precise Modeling Of Capacitor

Chip can be found everywhere in modern electronic products, with the development of manufacture technics and demand of application, its integration is higher and higher. However, the power noise will inevitably appear in high speed and high density chip, and its power supply pins will introduce large external power noise in the circuit also. So the influence caused by the power noise to the circuit has become the bottle neck of high-speed PCB design.The purpose of this project is to develop an instrument which can solve the power integrity (PI) problems during the pre-simulation stage, it allows the power distribution network in the circuit board providing pure power for chips. This paper is based on the structure of the power distribution network, and it gives detailed analysis of the influence of each component to the whole network. As a result, it has found out a main design method of power distribution network, selecting the best value and number of the decoupling capacitors. Based on the demand of the accurate capacitor model, this paper described the theory of the rational function modeling method and vector fitting method in detail, and establishes the accurate capacitor model by combining the two methods. Finally, combining MATLAB GUI tool, the accurate capacitor model we developed, and the filter capacitor selection method, the paper introduced the development progress of PI optimization pre-simulation tools.The accurate capacitor modeling method described in this paper has been compared with the actual measurement data, and the results fully meet the requirements in this project.