학술논문

Investigation of the Radiation Mechanism of Heatsinks Based on Characteristic Mode Theory
Document Type
Periodical
Source
IEEE Transactions on Electromagnetic Compatibility IEEE Trans. Electromagn. Compat. Electromagnetic Compatibility, IEEE Transactions on. 65(5):1446-1454 Oct, 2023
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Heat sinks
Magnetic moments
Integrated circuit modeling
Geometry
Electromagnetic compatibility
Dipole antennas
Magnetic resonance imaging
Characteristic mode
dipole moment
electromagnetic interference (EMI) mitigation
grounding design
heatsink
radiation mechanism
Language
ISSN
0018-9375
1558-187X
Abstract
Heatsinks may cause radiated emission and radio frequency interference problems when they are mounted on printed circuit boards. In this article, the radiation mechanism of heatsinks is systematically investigated using characteristic mode theory. The dipole moment is a commonly used equivalent source model for integrated circuits that drive radiated emission from heatsinks. On the basis of a simplified modal weighting coefficient formulation, the interactions between the dipole moment and the significant modes of the heatsink are efficiently evaluated, thus providing a clear physical insight into noise source placement. Finally, the grounding post design, a commonly used EMI mitigation method, is also discussed. The relative error of the mode-based field prediction is less than 3 dB compared with the full-wave simulation.