This paper analyzes the fundamental behavior of PCB power bus structures using the modal expansion method. The results are validated by experiments and full-wave numerical modeling. It is shown that the power bus can be modeled as a series LeC circuit below the first board resonance frequency. C is the interplane capacitance and Le is an effective inductance contributed by all the cavity nodes. The effects of the layer thickness, port location, board size and the feeding wire radius on the value of Le are discussed in this study. Le can be estimated from the geometry parameters of the test board. The goal is to obtain a simple model that can be used to analyze the power bus impedance below the first board resonance.

Meeting Name

IEEE International Symposium on Electromagnetic Compatibility (2000: Aug. 21-25, Washington, DC)


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

EMC; EMI; PCB Design; PCB Power Bus Structures; Board Size; Cavity Modes; Circuit Resonance; Closed-Form Expression; Earthing; Effective Inductance; Electric Impedance; Electromagnetic Compatibility; Electromagnetic Interference; Experiments; Feeding Wire Radius; First Board Resonance Frequency; Full-Wave Numerical Modeling; Geometry Parameters; Input Impedance; Interplane Capacitance; Layer Thickness; Modal Expansion Method; Passive Networks; Port Location; Power Bus Impedance; Power Electronics; Power-Ground Plane Structures; Printed Circuit Design; Series LC Circuit; Test Board; Wires (Electric)

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 2000 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Aug 2000