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To estimate electromagnetic interference (EMI) results of differential high-speed input/output interfaces more quickly, an partition method is proposed by separating system into source generation part and radiation part. Also, the partition analysis can help find contribution of differential-mode (DM) and common-mode (CM) to the unwanted radiation. A measurement validation on HDMI assesses the computational efficiency of proposed analysis by comparing with that of conventional full-wave simulation.

A novel electromagnetic bandgap (EBG) structure is proposed for broadband suppression of gigahertz simultaneous switching noise. The structure is composed of three-dimensional interdigital capacitors (3D-IDC) and series U-shaped transmission lines periodically. The EBG structure can be miniaturized based on the LTCC fabrication technology. A theoretical circuit model which considers the inductive coupling in the 3D-IDC will be developed to predict the stopband. The accuracy of the proposed model will be verified by comparing with both the full-wave simulation and the measurement results. This modeling method is also employed to study the variation of bandgap dependent on different geometrical parameters for the 3D-IDC and the U-shaped transmission line. A prototype is implemented using the LTCC technology with the dimension 1.2 mm × 3.8 mm × 0.728 mm. Both simulation and measurement show the rejection band is from 2 to 5.5 GHz. Over 45 dB noise reduction in the stop band could be achieved. In addition, the suppressive ability is also verified in the chip-package co-simulation. From the simulation result, significant reduction of power noise could be found both in digital and mixed signal circuits.

Mitigating power distribution network (PDN) noise is one of the main efforts for power integrity (PI) design in high-speed or mixed-signal circuits. Possible solutions, which are based on decoupling or isolation concept, for suppressing PDN noise on package or printed circuit board (PCB) levels are reviewed in this paper. Keeping the PDN impedance very low in a wide frequency range, except at dc, by employing a shunt capacitors, which can be in-chip, package, or PCB levels, is the first priority way for PI design. The decoupling techniques including the planes structure, surface-mounted technology decoupling capacitors, and embedded capacitors will be discussed. The isolation approach that keeps part of the PDN at high impedance is another way to reduce the PDN noise propagation. Besides the typical isolation approaches such as the etched slots and filter, the new isolation concept using electromagnetic bandgap structures will also be discussed.

Based on the ground surface perturbation concept, a novel stopband-enhanced electromagnetic-bandgap (EBG) structure has been proposed to suppress the power/ground noise on a three-layer package. This structure consists of a coplanar periodic pattern on the top layer, a ground plane on the third layer, and a ground surface perturbation lattice on the second layer with eight vias connecting to the ground plane. By designing the dimension and via numbers, the ground surface perturbation lattice can significantly enhance the stopband bandwidth. A generic 1-D circuit model is proposed for the three-layer EBG structure. The reason why the proposed structure can possess wider stopband will be explained. Several test samples are fabricated. The agreement of the stopband between the circuit model and measured results are good.

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.

An efficient numerical approach based on the 2-D finite-difference time-domain (FDTD) method is proposed to model the power/ground plane noise or simultaneously switching noise (SSN), including the interconnect effect between the package and the print circuit board (PCB). The space between the power and ground planes on the package and PCB are meshed with 2-D cells. The equivalent R-L-C circuits of the via and the solder balls connecting the package and PCB can be incorporated into a 2-D Yee cell based on a novel integral formulation in the time domain. An efficient recursive updating algorithm is proposed to fit the lumped networks into the Yee equations. A test sample of a ball grid array (BGA) package mounted on a PCB was fabricated. The power/ground noise coupling behavior was measured and compared with the simulation. The proposed method significantly reduces the computing time compared with other full-wave numerical approaches.

A power/ground planes design for efficiently eliminating the ground bounce noise (GBN) in high-speed digital circuits is proposed by using low-period coplanar electromagnetic bandgap (LPC-EBG) structure. Keeping solid for the ground plane and designing an LPC-EBG pattern on the power plane, the proposed structure omnidirectionally behaves highly efficiently in suppression of GBN (over 50 dB) within the broad-band frequency range (over 4 GHz). In addition, the proposed designs suppress radiated emission (or electromagnetic interference) caused by the GBN within the stopband. These extinctive behaviors of low radiation and broad-band suppression of the GBN is demonstrated numerically and experimentally. Good agreements are seen. The impact of the LPC-EBG power plane on the signal integrity for the signals referring to the power plane is investigated. Two possible solutions, differential signals and an embedded LPC-EBG power plane concept, are suggested and discussed to reduce the impact.

A novel L-bridged electromagnetic bandgap (EBG) power/ground planes is proposed with super-wideband suppression of the ground bounce noise (GBN) from 600Mz to 4.6GHz. The L-shaped bridge design on the EBG power plane not only broadens the stopband bandwidth, but also can increase the mutual coupling between the adjacent EBG cells by significantly decreasing the gap between the cells. It is found the small gap design can prevent from the severe degradation of the signal quality for the high-speed signal referring to the perforated EBG power plane. The excellent GBN suppression performance with keeping reasonably good signal integrity for the proposed structure is validated both experimentally and numerically. Good agreement is seen.

The co-design of chip-package-PCB is imperative for a modern wireless receiver to achieve the best circuit performance. This paper proposes simulation-based co-design methodologies which can accurately predict the package and PCB parasitic effects on the low noise amplifier (LNA). To begin with, a chip-package co-design methodology is put forth for the LNA circuit to design its inductive degeneration in package. Then the PCB parasitic effects are included in the circuit simulation as well. The favorable topology of impedance matching network is thus evaluated and the associated SMT values can be determined methodically. By applying the proposed co-design methodologies, the receiver performance is able to be optimized in the circuit design phase.

A photonic crystal fence (PCF) is proposed for noise isolation with minimum use of high dielectric constant (DK) rods material. Only three rows of periodic high-DK rods are used in the PCF, but broadband and high efficient noise suppression are retained. It will be shown that a 45° rotated square lattice represents a good compromise in terms of both high-DK material reduction (cost reduction) and noise suppression performance. A design flow for choosing the high-DK rod radius, pitch, and dielectric constant for the PCF is also demonstrated.

A new structure to suppress simultaneous switching noise using an electromagnetic band gap filter is proposed. Based on periodic structure concept, this structure is one dimensional periodic structure with three unit cells. The size is comparable with noise suppression component such as capacitors, ferrite beads and π filters. But unlike these components, the proposed structure would not suffer from noise problems at higher frequencies. The special characteristic is its flexible operation frequency. The band gap can be designed by using proper geometrical structure parameter. To make use of the parameter in this work, the noise beyond limitation of the π filter could be suppressed by this structure. In this work, the size of proposed structure is 1.2mmx 3.8mmx0.728mm. The stop band is from 2GHz to 5.5GHz and is validated both by simulation and experiment. Over 25dB noise reduction in the stop band could be achieved by this structure.

A novel macro-via crystal (MVPC) structure is proposed for suppression of PPNs in high-speed or mixed signal circuit package. This structure is designed by periodically embedding macro-via cylinders, which consist of six vias and two circular pads, between the power and ground planes. Compared with previously proposed EBG structures, several advantages have been demonstrated. First, etching slots or high-density vias are not required. It will have better SI and PI performance for the package. Second, it can be fabricated in the typical and low-cost package process. Third, significant routing space is available on the layers between power and ground planes. A test sample was fabricated in the package substrate. Excellent PPN suppression has been presented from 1.8 GHz to 5.6 GHz. Agreement between the measurement and simulation is favorably good.

Based on the slow-wave concept, an EBG power planes with stopband enhancement is proposed by using ground surface perturbation lattice (GSPL) between the coplanar EBG power and ground planes. This structure has 73% and 100% stopband enhancement, respectively, compared to the conventional coplanar and mush-room typed EBG planes. A test sample of 16 unit-cells on a 40 mm square substrate is fabricated with 4 GHz stopband and is validated both by simulation and experiment. It is a low-cost design in SiP because no high-K material is required. Two test chips, C-band LNA (5.6 GHz) and off-chip digital drivers (1.3 GHz), is designed and integrated on the EBG substrate. In the chip-package co-simulation, over 40 dB suppression for the 1.3 GHz harmonics noise on the LNA output is seen for the proposed EBG planes.

A novel low-cost filter design for common-mode noise suppression in high-speed differential signals is proposed. It is realized by etching a HU-shaped defected-ground structure (DGS) to perturb the return current of the common-mode noise. A simple LC resonator model for the proposed structure is also developed with good agreement to the full-wave simulation and measurement result. It is found that over 15 dB of common-mode noise suppression can be achieved over a wide frequency ranges from 3.6 to 9.1 GHz, 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.

A novel hybrid photonic crystal power/ground layer (H-PCPL) concept is proposed with broadband power noise isolation (or suppression) performance. Two different hybrid approaches are investigated, one is fixed radius but varied pitch for the high-DK disc and the other one is varied radius and pitch for the disc. It is found the first approach can enhance the bandwidth of the noise rejection but can not obtain a continuous and wide stopband because there is an absolute passband between two gaps. However, the second approach can obtain a continuous and wide stopband by mixing two radius of the disc. Gap map of the photonic crystal lattice is employed to synthesize the stopband profile in both approaches. As an example, a wide stopband ranging from 2.8 GHz to 7.9 GHz can be achieved based on two kinds of radius, 2 mm and 1.45 mm, under the same disc pitch 10 mm.

A novel L-bridged frequency selective surface (FSS) power/ground planes is proposed with super-broadband rejection for simultaneous switch noise (SSN) from 600 Mz to 4.6 GHz. The L-shaped bridge design on the FSS power plane not only broadens the stop-band bandwidth, but also increases the mutual coupling between the adjacent FSS cells with allowing the significant decrease of the gap between the cells. It is found the small gap design can ease the degradation of the signal quality for the signal referring to the perforated FSS power plane. The excellent SSN suppression performance with keeping reasonably good signal integrity for the proposed structure is validated both experimentally and numerically. Good agreement is seen.

This paper proposes a novel embedded band selective (EBS) power plane with 10GHz stopband bandwidth. A four-layer laminate package with the dimension of 4cm square is used to implement the concept. Because the hybrid-cell periodic structure (HCPS) designed on the power/ground planes selects different rejection band, this novel embedded power/ground plane design behaves over 60dB SSN suppression from 1.5GHz up to 11.5GHz. This excellent behavior is validated both by simulation and measurement.