Noise reduction and design methodology in mixed-signal systems with alternating impedance electromagnetic bandgap (AI-EBG) structure

This paper presents noise suppression and design methodology in mixed-signal systems with alternating impedance electromagnetic bandgap (AI-EBG) structure. The AI-EBG structure was developed recently and applied for noise isolation/suppression in mixed-signal systems. In this paper, the mixed-signal systems with and without the AI-EBG structure were designed and fabricated to see noise reduction effect due to AI-EBG structure. This AI-EBG structure showed excellent noise suppression in mixed-signal systems by suppressing all harmonic noise peaks due to digital circuits in a stopband range of -100 dB isolation (S₂₁) level. However, without carefully designing mixed-signal system with the AI-EBG structure, the use of the AI-EBG structure could cause problems associated with signal integrity as well as electromagnetic interference (EMI). In this paper, excellent noise suppression with AI-EBG structure is shown and design methodology in mixed-signal systems with AI-EBG structure is proposed to avoid possible problems associated with signal integrity as well as EMI.