关键词: 多负载电源分配网络, 多输入叠加阻抗, 矢量拟合

Abstract:

The traditional design method of power distribution network by using frequency domain target impedance is mainly used for the circumstance that one plane own one chip. But it no longer applies to the today’s complex power distribution networks in which multiple chips share one power plane. This paper utilizes the multiple superimposed impedances extracted from full-wave simulation software SI-wave to guide the design of complex PDN. The rational function of multiple superimposed impedance of every chip is obtained by the fitting algorithm, and then imported into the decoupling capacitor select algorithm to get the decoupling scheme of each chip. The result of experiment shows that the power noise of IC is within the allowable 5% range after adding the decoupling capacitor to the power/ground plane.

Key words: multi load power distributed networks, multi-input superimposed impedance, vector fitting