Design of EBG Power Distribution Networks With VHF-Band Cutoff Frequency and Small Unit Cell Size for Mixed-Signal Systems

Hybrid electromagnetic bandgap (EBG) power distribution networks (PDNs) with VHF-band cutoff frequency, small unit cell size, and wideband noise suppression characteristics are proposed. Commercial lumped chip inductors are used to implement inductive bridges between neighboring metal patches instead of conventional microstrip lines. A 1D analysis model of the EBG structure is developed to find a mathematical ground for the use of the lumped chip inductors in the EBG PDN designs. From 158 MHz to 4528 MHz a measured stopband bandwidth of 4.37 GHz is achieved with over -60 dB noise suppression levels.     

一种基于互补环缝谐振器抑制SSN的新方法

针对高速PCB上抑制同步开关噪声(SSN)的问题,提出了一种将互补环缝谐振器(CSRR)刻蚀在电源平面上,抑制电源/地平面间的电场波动噪声传播的方法。采用基于有限元算法的HFSS软件对该结构进行仿真分析,结果表明:与理想参考平面和电磁带隙结构相比,刻蚀了该CSRR结构的电源分配网络具有较好的宽带全向SSN噪声抑制能力,在抑制深度为-40 dB时,其阻带覆盖从0.26 GHz到超过20 GHz以上的频率范围。     

Suppression of GHz range power/ground inductive impedance and simultaneous switching noise using embedded film capacitors in multilayer packages and PCBs

We measured and demonstrated the great advantages of embedded film capacitors in reducing power/ground inductive impedance and the suppression of SSN at frequencies up to 3 GHz for high-performance multilayer packages and PCBs. Eight-layer test PCBs were fabricated, and their inductive power/ground network impedances were measured as a function of film thickness, via distribution, and combined use with discrete decoupling capacitors, using a two-port self-impedance measurement method. This successfully demonstrated that the power/ground inductive impedance was reduced from 270 pH to 106 pH simply by using an embedded film capacitor instead of 16 discrete decoupling capacitors.     

Analysis of power delivery network constructed by irregular-shaped power/ground plane including densely populated via-hole

The high speed and low power trend has imposed more and more importance on the design of the power distribution network (PDN) using multilayer printed circuit boards (PCBs) for modern microelectronic packages. This paper presents a fast and efficient analysis methodology in frequency domain for the design of a PDN with a power/ground plane pair, which considers the effect of irregular shape of the power/ground plane and densely populated via-holes. The presented method uses parallel-plate transmission line theory with equivalent circuit model of unit-cell grid considering three-dimensional geometric boundary conditions. Characteristics of PDNs implemented by perforated planes including a densely populated via-hole structure is quantitatively determined based on full-wave analysis using the finite-difference time-domain (FDTD) periodic structure modeling method and full-wave electromagnetic field solver. Using a circuit simulator such as popularly used SPICE and equivalent circuit models for via-hole structure and perforations, the authors have analyzed input-impedance of the power/ground plane pair. Since the presented method gives an accurate and fast solution, it is very useful for an early design of multilayer PCBs.     

An electromagnetic bandgap resonator antenna

This paper introduces a new explanation of the electromagnetic bandgap (EBG) material properties using the study of the EBG structures in the frequency domain and reciprocal space. Once the behavior of such a material is understood, the properties of the EBG are used in order to make an EBG antenna. The antenna is realized with dielectric EBG rods. Its directivity is increased compared to a simple patch antenna. Such a device allows us to obtain a high gain with a very thin structure.     

Multi‐stack Technique for a Compact and Wideband EBG Structure in High‐Speed Multilayer Printed Circuit Boards

We propose a novel multi‐stack (MS) technique for a compact and wideband electromagnetic bandgap (EBG) structure in high‐speed multilayer printed circuit boards. The proposed MS technique efficiently converts planar EBG arrays into a vertical structure, thus substantially miniaturizing the EBG area and reducing the distance between the noise source and the victim. A dispersion method is presented to examine the effects of the MS technique on the stopband characteristics. Enhanced features of the proposed MS‐EBG structure were experimentally verified using test vehicles. It was experimentally demonstrated that the proposed MS‐EBG structure efficiently suppresses the power/ground noise over a wideband frequency range with a shorter port‐to‐port spacing than the unit‐cell length, thus overcoming a limitation of previous EBG structures.     

EBG Superstrate Array Configuration for the WAAS Space Segment

Two different electromagnetic bandgap (EBG) superstrate array antenna configurations, intended for the Wide Area Augmentation Service space segment, are presented in this paper. The described antenna configurations take advantage of the directivity enhancement produced by a semireflective sheet placed parallel to a metallic ground plane. The first design presented is realized using a 2$,times,$ 2 circularly polarized (CP) patch array illuminating an EBG superstrate composed of a square pattern of circular holes etched in a thin metallic sheet. The second design consists of a 2$,times,$ 2 CP helix array feeding a hexagonal pattern of holes etched into a metallic EBG superstrate. Both configurations have been designed, breadboarded, and measured, and excellent agreement between simulations and measurements has been recorded. The accurate control of the antenna pattern phase center variation with both the frequency and the antenna field of view, necessary for the intended navigation antenna application, has been the principal challenge of this work. The EBG technology designs presented here are simpler than conventional navigation antennas and can lead to cost reduction, beamforming network simplification, and height reduction while offering similar radio-frequency performances to equivalent products realized in conventional technology.      

On the optimal radiation bandwidth of printed slot antennas surrounded by EBGs

This paper describes a design strategy to achieve the maximum bandwidth and efficiency for a printed slot antenna surrounded by EBGs. First the dielectric constant and the thickness of the dielectric slab that guarantees an acceptable front to back radiation ratio is identified. Then electromagnetic bandgap (EBG) structures are designed to achieve the optimal bandwidth (BW) while obtaining high surface wave efficiency in the radiating half space. To achieve this goal the wave interaction between the slot and the EBG structures is investigated in depth and clearly described. For the case of Planar circularly symmetric (PCS) EBGs the maximum of radiation BW is shown to occur when the distance between the central antenna and the EBG is approximately half wavelength of the first surface wave, /spl lambda//sub sw//2.     

A novel power plane with super-wideband elimination of ground bounce noise on high speed circuits

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.     

Experimental woodpile EBG waveguides, bends and power dividers at microwave frequencies

Experimental waveguides, bends and power dividers in the woodpile electromagnetic bandgap (EBG) material at Ku-band are demonstrated. Prototypes are fabricated from alumina, and use an efficient waveguide transition to enable high quality measurements. Low-loss transmission is demonstrated for a waveguide and a 90/spl deg/ bend, and near equal power division shown for a woodpile EBG waveguide power divider. The components have the potential to be scaled for applications at millimetre-wave and terahertz frequencies     

Analysis of noise coupling from a power distribution network to signal traces in high-speed multilayer printed circuit boards

As layout density increases in highly integrated multilayer printed circuit boards (PCBs), the noise that exists in the power distribution network (PDN) is increasingly coupled to the signal traces, and precise modeling to describe the coupling phenomenon becomes necessary. This paper presents a model to describe noise coupling between the power/ground planes and signal traces in multilayer systems. An analytical model for the coupling has been successfully derived, and the coupling mechanism was rigorously analyzed and clarified. Wave equations for a signal trace with power/ground noise were solved by imposing boundary conditions. Measurements in both the frequency and time domains have been conducted to confirm the validity of the proposed model.     

Suppression of EMI and Electromagnetic Noise in Packages Using Embedded Capacitance and Miniaturized Electromagnetic Bandgap Structures With High-k Dielectrics

A novel miniaturized simple planar electromagnetic bandgap (EBG) structure is proposed. The new structure mitigates different types of electromagnetic noise in packages. The design of the new EBG structure proposed here relies on the use of high-k dielectric material (epsiv_r >100), and consists of Meander lines and patches. The Meander lines serve to provide current continuity bridges between the capacitive patches. High-k dielectric material increases the capacitance of the patches substantially in comparison to commonly used material with much lower dielectric constant. Simulation results are provided to show that using the proposed EBG, it is possible to obtain a very wide stop band (~ 10 GHz) which covers the operating frequency of current processors and a wide range of the resonant frequencies of a typical package. The wideband is obtained using a unit cell of less than 2 mm.     

An interconnected 2D-TM EBG structure for millimeter and submillimeter waves

Due to their unique properties, electromagnetic bandgap (EBG) materials are of high interest for applications in communication technology for many frequency bands from microwave up to optical frequencies. We have investigated in both simulation and experiment a two dimensionally periodic EBG structure made by reactive ion etching of silicon with a bandgap for transverse magnetic waves in the millimeter wave range around 100 GHz. The structure comprises both a large bandgap and a high mechanical stability due to interconnecting dielectric bridges.     

薄膜绝缘层对陶瓷厚膜电致发光显示器件的影响

采用丝网印刷技术，在Al2O3陶瓷板上印刷、高温烧结内电极及绝缘层制备出陶瓷厚膜基板，进而制备了新型厚膜电致发光显示器（TDEL），整个器件结构为陶瓷基板／内电极／厚膜绝缘层／发光层／薄膜绝缘层／ITO透明电极。对用不同薄膜绝缘材料制备的显示器件的特性进行测试、比较、分析，结果表明薄膜绝缘介质层对器件的阈值电压、发光亮度均有一定的影响，以复合绝缘层的性能最优。最后对器件的衰减特性进行了初步分析。     

Design of Novel Compact Electromagnetic Bandgap Structures with Enhanced Bandwidth

Two kinds of compact electromagnetic band gap （EBG） structures are designed. A two layer compact EBG structure configured with cross spiral shape line inductors and interdigital capacitors is first presented. Because of its significantly enlarged equivalent inductor and capacitance, the period of the lattice is approximately 4.5% of the free space wavelength. By insetting several narrow slits in the ground plane, the bandwidth of the main bandgap is enhanced by nearly 19%. Further effort has been made for designing a three layer compact EBG structure. Simulation results show that its period is reduced by about 26% compared to that of proposed two layer EBG structure, and the bandwidth of the main bandgap is about 3 times as that of the proposed two layer EBG structure. The detailed designs including a two layer compact 3×7 EBG array with and without defect ground plane and the three layer EBG array are given and simulation results are presented.     

Woodpile EBG phase shifter

A phase shifter in an alumina woodpile electromagnetic bandgap (EBG) defect waveguide that operates at microwave frequencies is demonstrated. The phase shift is introduced by sequentially adding low dielectric constant rods to the voids directly above the defect waveguide. The addition of the extra rods creates selected phase delay without significantly affecting the transmission performance of the woodpile waveguide. Measured and computed results in Ku-band are presented to confirm the performance of the device     

A S-Bridged Inductive Electromagnetic Bandgap Power Plane for Suppression of Ground Bounce Noise

In this letter, a novel power plane using an inductive S-bridged electromagnetic bandgap (EBG) is proposed for ultra wideband suppression of the ground bounce noise. The S-shaped bridge detouring unit cells effectively increase the power plane inductance. -30 dB stopband is realized from 220 MHz to 7 GHz. The stopband lower limit (220 MHz) of the proposed EBG has been greatly reduced from that (550 MHz) of L-bridged EBG. It is expected that the number of local decoupling capacitors for the power plane integrity is reduced using the proposed S-bridged EBG without the self resonance effect.     

Ultra-Wideband Mitigation of Simultaneous Switching Noise Using Novel Planar Electromagnetic Bandgap Structures

A novel design of power/ground plane with planar electromagnetic bandgap (EBG) structures for suppressing simultaneous switching noise (SSN) is presented. The novel design is based on using meander lines to increase the effective inductance of EBG patches. A super cell EBG structure, comprising two different topologies on the same board, is proposed to extend the lower edge of the band. Both novel designs proposed here are validated experimentally. A$-$28dB suppression bandwidth starting at 250MHz and extending to 12GHz and beyond is achieved.     

Power bus signal integrity improvement and EMI mitigation on multilayer high-speed digital PCBs with embedded capacitance

The continuous technology trend in the telecommunication market toward higher operating frequencies and high processing performances will give rise to new sophisticated chip sets, processors, and RF transceivers which will demand new feature to the PCB designs. As the complexity of the integrated circuits increases, signal integrity (SI) and electromagnetic compatibility (EMC) become key elements in the board design process. This paper analyzes the beneficial effects that a thin dielectric material between a pair of power and ground layers (embedded capacitance) has both in reducing power bus resonance amplitudes (SI approach) and radiated emissions (EMC approach) as well. Scattering parameter measurements carried out on the power bus of two production boards are presented and correlated with the electric field strength measurements conducted on the same boards in a semianechoic chamber.     

Partial EBG Structure with DeCap for Ultra‐wideband Suppression of Simultaneous Switching Noise in a High‐Speed System

To supply a power distribution network with stable power in a high‐speed mixed mode system, simultaneous switching noise caused at the multilayer PCB and package structures needs to be sufficiently suppressed. The uniplanar compact electromagnetic bandgap (UC‐EBG) structure is well known as a promising solution to suppress the power noise and isolate noise‐sensitive analog/RF circuits from a noisy digital circuit. However, a typical UC‐EBG structure has several severe problems, such as a limitation in the stop band's lower cutoff frequency and signal quality degradation. To make up for the defects of a conventional EBG structure, a partially located EBG structure with decoupling capacitors is proposed in this paper as a means of both suppressing the power noise propagation and minimizing the effects of the perforated reference plane on the signal quality. The proposed structure is validated and investigated through simulation and measurement in both frequency and time domains.