Summary
International Symposium on Electromagnetic Compatibility
2009
Session Number:22Q2
Session:
Number:22Q2-3
Lumped Resonances and the Corresponding Noise Coupling Mechanism in Flex PCBs
S. Wu,
pp.349-352
Publication Date:2009/7/20
Online ISSN:2188-5079
Summary:
A flex PCB design with multiple traces and a discontinuous ground plane demonstrates multiple resonances in its insertion loss at the frequencies lower than 1 GHz. This paper investigates the root cause of these resonances. An equivalent circuit based on a multi-conductor transmission-line approach is developed, and the noise coupling mechanism is studied using this equivalent circuit. The resonances are found to be caused by the mutual inductances among the traces in the region without the ground plane and the self capacitances of the neighbouring open-ended traces.