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A novel power/ground plane for eliminating the power noise in the high-speed digital circuits using an artificial substrate electromagnetic bandgap (AS-EBG) structure is proposed. The AS-EBG is designed by embedding the air rods and high dielectric constant (DK) rods between the coplanar EBG power/ground planes to enhance the stopband bandwidth. A 2-D transmission-line model of the AS-EBG power planes is also developed with experimental verification to explain the mode perturbation and predict the bandgap of the AS-EBG. It is found that over 60% enhancement of bandwidth (from 1.5 to 2.4 GHz) can be achieved for a 3 times 3 AS-EBG power plane compared to the coplanar-EBG power planes by proper design of the high DK rod with DK of 92. Based on SPICE-based modeling, the excellent power/signal integrity performance of the AS-EBG structure is also presented by the chip-package co-simulation in the time domain. It is found over 70% reduction of the simultaneously switching noise can be obtained with good signal eye-diagram improvement.

A novel low-cost filter design for common-mode noise suppression in high-speed differential signals is proposed. It is realized by periodically etching the dumbbell-shape defected ground structure (DGS) to perturb the return current of the common- mode noise. A transmission-line model for the proposed structure is also developed with good agreement to the full-wave simulation and measurement result. It is found that over 20 dB suppression of common-mode noise can be achieved over a wide frequency range from 3.3 to 5.7 GHz with 3 cascaded DGS cells, while the differential signals still keep good signal integrity in eye-pattern observation. The common-mode current, which generally results in common-mode EMI, on the attached input/output cable is also proved to be efficiently suppressed (15 dB in average) within the stopband by the proposed filter.

A novel low-cost filter design for common-mode noise suppression in high-speed differential signals is proposed. It is realized by periodically etching the dumbbell-shape defected ground structure (DGS) to perturb the return current of the common-mode noise. A transmission-line model for the proposed structure is also developed with good agreement to the full-wave simulation and measurement result. It is found that over 20 dB of common-mode noise suppression can be achieved over a wide frequency ranges from 3.3 to 5.7 GHz with 3 cascaded DGS cells, while the differential signals still keep good signal integrity in eye-pattern observation.

Based on the conventional low-period coplanar EBG (LPC-EBG) structure, a novel power plane is proposed to extend the bandwidth of the stopband for ground bounce elimination using artificial substrate EBG (AS-EBG) structure. With properly embedded high-K rods and air rods in the substrate of the LPC-EBG power plane, the resonance frequencies can be shifted and thus result in the enhancement of the first stopband. Over 60% improvement of the stopband bandwidth can be achieved in this work. This improvement is also verified by the dispersion diagram calculated using the 2-D transmission-line model.