Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Electrical and Computer Engineering Faculty Research & Creative Works

Printed Circuits

Articles 1 - 30 of 60

Full-Text Articles in Engineering

Esd Current Spread Measurement Using Mesh Structure, Jae-Deok Lim, David Pommerenke, Jong-Sung Lee, Byong-Su Seol Jan 2009

Esd Current Spread Measurement Using Mesh Structure, Jae-Deok Lim, David Pommerenke, Jong-Sung Lee, Byong-Su Seol

Electrical and Computer Engineering Faculty Research & Creative Works

If a PCB is struck by an ESD the injected current spreads throughout the PCB and returns via attached cables. During the current spread a variety of effects occur: The current spreads on the main ground and power planes, couples into traces and IC lead-frames and bond wires. Further, the PCB and the attached cables can form resonators causing ringing at their natural resonance frequencies. Understanding the current spread onto a PCB, best, also onto the traces is of great importance for gaining insight into ESD related problems on products. A test setup has been created that allows capturing and …


Noise Coupling Between Power/Ground Nets Due To Differential Vias Transitions In A Multilayer Pcb, Matteo Cocchini, Jun Fan, Bruce Archambeault, James L. Knighten, Xin Chang, James L. Drewniak, Yaojiang Zhang, Samuel R. Connor Aug 2008

Noise Coupling Between Power/Ground Nets Due To Differential Vias Transitions In A Multilayer Pcb, Matteo Cocchini, Jun Fan, Bruce Archambeault, James L. Knighten, Xin Chang, James L. Drewniak, Yaojiang Zhang, Samuel R. Connor

Electrical and Computer Engineering Faculty Research & Creative Works

Due to the increase in board density, routing traces on different layers becomes a widely used strategy. Through-hole vias are often used to connect these traces. Those vias that penetrate power/ground plane pairs could cause noise coupling between signal and power/ground nets. At the same time, the need for clean signal transmitted to receivers results in a wide use of differential signals. This paper studies the noise coupling mechanism caused by a differential pair of vias penetrating power/ground plane pair using a physics-based via-plane model combined with transmission line models for traces. A 26-layer printed circuit board with a pair …


Estimating Maximum Radiated Emissions From Printed Circuit Boards With An Attached Cable, Shaowei Deng, Todd H. Hubing, Daryl G. Beetner Feb 2008

Estimating Maximum Radiated Emissions From Printed Circuit Boards With An Attached Cable, Shaowei Deng, Todd H. Hubing, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

The common-mode current induced on cables attached to printed circuit boards can be a significant source of radiated emissions. Previous studies have shown that coupling from electric and magnetic field sources on circuit boards can be effectively modeled by placing equivalent voltage sources between the board and the cable. The amplitude of these equivalent sources can be estimated by using closed-form equations; however, estimates of the radiated emissions from these board-cable geometries have required full-wave simulations, and full-wave simulation results depend on the exact cable length and placement, which are not normally fixed during radiated emissions testing. This paper develops …


Modeling Noise Coupling Between Package And Pcb Power/Ground Planes With An Efficient 2-D Fdtd/Lumped Element Method, Ting-Kuang Wang, Sin-Ting Chen, Chi-Wei Tsai, Sung-Mao Wu, James L. Drewniak, Tzong-Lin Wu Nov 2007

Modeling Noise Coupling Between Package And Pcb Power/Ground Planes With An Efficient 2-D Fdtd/Lumped Element Method, Ting-Kuang Wang, Sin-Ting Chen, Chi-Wei Tsai, Sung-Mao Wu, James L. Drewniak, Tzong-Lin Wu

Electrical and Computer Engineering Faculty Research & Creative Works

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 …


Early Time Charge Replenishment Of The Power Delivery Network In Multi-Layer Pcbs, Giuseppe Selli, Matteo Cocchini, James L. Knighten, Bruce Archambeault, Jun Fan, Samuel R. Connor, Antonio Orlandi, James L. Drewniak Jul 2007

Early Time Charge Replenishment Of The Power Delivery Network In Multi-Layer Pcbs, Giuseppe Selli, Matteo Cocchini, James L. Knighten, Bruce Archambeault, Jun Fan, Samuel R. Connor, Antonio Orlandi, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

The investigation of decoupling issues has been extensively treated in the literature in both the frequency and the time domain [1-9]. The two domains describe from different perspectives the same physical phenomenon, being related by a Fourier transform. In this article, well known decoupling issues usually addressed in the frequency domain [1,2] are discussed in the time domain. Moreover, some modeling issues related to the cavity model approach are discussed and, in particular, the circuit extraction feature associated with this methodology is utilized throughout the article to carry out the time domain simulations within a SPICE based-tool. The depletion of …


Circuit Models For Power Bus Structures On Printed Circuit Boards Using A Hybrid Fem-Spice Method, Todd H. Hubing, Chunlei Guo Jan 2006

Circuit Models For Power Bus Structures On Printed Circuit Boards Using A Hybrid Fem-Spice Method, Todd H. Hubing, Chunlei Guo

Electrical and Computer Engineering Faculty Research & Creative Works

Power bus structures consisting of two parallel conducting planes are widely used on high-speed printed circuit boards. In this paper, a full-wave finite-element method (FEM) method is used to analyze power bus structures, and the resulting matrix equations are converted to equivalent circuits that can be analyzed using SPICE programs. Using this method of combining FEM and SPICE, power bus structures of arbitrary shape can be modeled efficiently both in the time-domain and frequency-domain, along with the circuit components connected to the bus. Dielectric loss and losses due to the finite resistance of the power planes can also be modeled. …


A Closed-Form Expression For Estimating Radiated Emissions From The Power Planes In A Populated Printed Circuit Board, Todd H. Hubing, Hwan-Woo Shim Jan 2006

A Closed-Form Expression For Estimating Radiated Emissions From The Power Planes In A Populated Printed Circuit Board, Todd H. Hubing, Hwan-Woo Shim

Electrical and Computer Engineering Faculty Research & Creative Works

An expression for the maximum intensity of radiated emissions from a rectangular power bus structure has been derived based on an analytical cavity-resonator model. The effect of components mounted on the board is modeled by modifying the propagation constant of the waves within the power bus structure. The radiated field intensity is calculated using the equivalent magnetic current around the edges of the power bus structure together with the modified propagation constant. Measurements of a populated test board show that the derived closed-form expression estimates the level of the maximum radiation intensity with reasonable accuracy.


Complex Power Distribution Network Investigation Using Spice Based Extraction From First Principle Formulations, Giuseppe Selli, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Dean Mccoy, Bruce Archambeault, Stefano Grivet-Talocia, Flavio G. Canavero Oct 2005

Complex Power Distribution Network Investigation Using Spice Based Extraction From First Principle Formulations, Giuseppe Selli, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Dean Mccoy, Bruce Archambeault, Stefano Grivet-Talocia, Flavio G. Canavero

Electrical and Computer Engineering Faculty Research & Creative Works

The modeling and the analysis of the power distribution networks (PDN) within multi-layer printed circuit board is crucial for the investigation of the performance of PCB systems. Carrying out such analyses in SPICE based tools has the advantage of being faster than the corresponding full-wave modeling and it allows obtaining both frequency and time domain results.


Coupling Between Differential Signals And The Dc Power-Bus In Multilayer Pcbs, Chen Wang, Marco Leone, James L. Drewniak, Antonio Orlandi May 2005

Coupling Between Differential Signals And The Dc Power-Bus In Multilayer Pcbs, Chen Wang, Marco Leone, James L. Drewniak, Antonio Orlandi

Electrical and Computer Engineering Faculty Research & Creative Works

Differential and common-mode transfer impedances are proposed herein to analyze noise coupled to (from) the dc power-bus from (to) via transitions in differential signals. Expressions for the two transfer impedances in terms of conventional single-ended transfer impedances are derived and verified through measurements, full-wave finite-difference time-domain (FDTD) simulations and an analytical cavity model. Some properties of the differential and common-mode transfer impedances are investigated to facilitate engineering design. The impact of signal current imbalances on power-bus noise and the benefit of differential signals as compared to single-ended signals are quantified.


Esd Susceptibility Characterization Of An Eut By Using 3d Esd Scanning System, Kai Wang, Jayong Koo, Giorgi Muchaidze, David Pommerenke Jan 2005

Esd Susceptibility Characterization Of An Eut By Using 3d Esd Scanning System, Kai Wang, Jayong Koo, Giorgi Muchaidze, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Electrostatic discharges (ESD) can lead to soft-errors (e.g., bit-errors, wrong resets etc.) in digital electronics. The use of lower threshold voltages and faster I/O increases the sensitivity. In the analysis of ESD problems, an exact knowledge of the affected pins and nets is essential for an optimal solution. In this paper, a three dimensional ESD scanning system which has been developed to record the ESD susceptibility map for printed circuit board is presented and the mechanisms that the ESD event couples into the digital devices is studied. The ESD susceptibility of a fast CMOS EUT is characterized by generating the …


Analytical Model For The Rectangular Power-Ground Structure Including Radiation Loss, Ji Chen, Todd H. Hubing, Weimin Shi, R. L. Chen Jan 2005

Analytical Model For The Rectangular Power-Ground Structure Including Radiation Loss, Ji Chen, Todd H. Hubing, Weimin Shi, R. L. Chen

Electrical and Computer Engineering Faculty Research & Creative Works

An accurate analytical model to predict via coupling within rectangular power-return plane structures is developed. Loss mechanisms, including radiation loss, dielectric loss, and conductor loss, are considered in this model. The radiation loss is incorporated into a complex propagating wavenumber as an artificial loss mechanism. The quality factors associated with three loss mechanisms are calculated and compared. The effects of radiation loss on input impedances and reflection coefficients are investigated for both high-dielectric-loss and low-dielectric-loss printed circuit boards. Measurements are performed to validate the effectiveness of this model.


Traces In Proximity To Gaps In Return Planes, Todd H. Hubing, Thomas Van Doren, Theodore M. Zeeff Jan 2005

Traces In Proximity To Gaps In Return Planes, Todd H. Hubing, Thomas Van Doren, Theodore M. Zeeff

Electrical and Computer Engineering Faculty Research & Creative Works

Coupling between circuitry on printed circuit boards can be mitigated by a variety of well-known techniques. One such technique is to isolate circuitry in different areas of the printed circuit board by strategically placing a gap in the signal return plane. However, this technique is only effective at reducing common-impedance coupling, which is generally not a significant coupling mechanism at frequencies above 1 MHz. This paper investigates the effect of a gap located between and parallel to adjacent microstrip traces. The effect of the gap on the mutual inductance and mutual capacitance is evaluated. Laboratory measurements and numerical simulations show …


Derivation Of A Closed-Form Approximate Expression For The Self-Capacitance Of A Printed Circuit Board Trace, Todd H. Hubing, Hwan-Woo Shim Jan 2005

Derivation Of A Closed-Form Approximate Expression For The Self-Capacitance Of A Printed Circuit Board Trace, Todd H. Hubing, Hwan-Woo Shim

Electrical and Computer Engineering Faculty Research & Creative Works

The electric fields that couple traces on printed circuit boards to attached cables can generate common-mode currents that result in significant radiated emissions. Previous work has shown that these radiated emissions can be estimated based on the self-capacitances of the microstrip structures on a board . In general, the determination of these self-capacitances must be done numerically using three-dimensional static modeling software. In this paper, an approximate closed-form expression for the self-capacitance of microstrip traces is derived. This expression can be used to estimate the voltage-driven common-mode emissions from boards with various microstrip trace geometries. The expression also provides insight …


Model For Estimating Radiated Emissions From A Printed Circuit Board With Attached Cables Due To Voltage-Driven Sources, Todd H. Hubing, Hwan-Woo Shim Jan 2005

Model For Estimating Radiated Emissions From A Printed Circuit Board With Attached Cables Due To Voltage-Driven Sources, Todd H. Hubing, Hwan-Woo Shim

Electrical and Computer Engineering Faculty Research & Creative Works

Common-mode currents induced on cables attached to printed circuit boards (PCBs) can be a significant source of unintentional radiated emissions. This paper develops a model for estimating the amount of common-mode cable current that can be induced by the signal voltage on microstrip trace structures or heatsinks on a PCB. The model employs static electric field solvers or closed-form expressions to estimate the effective self-capacitances of the board, trace, and/or heatsink. These capacitances are then used to determine the amplitude of an equivalent common-mode voltage source that drives the attached cables. The model shows that these voltage-driven common-mode cable currents …


A Time Domain Approach To Estimate Current Draw From Smt Decoupling Capacitors, Lin Zhang, Bruce Archambeault, Samuel Conner, James L. Knighten, Jun Fan, Norman W. Smith, Ray Alexander, Richard E. Dubroff, James L. Drewniak Aug 2004

A Time Domain Approach To Estimate Current Draw From Smt Decoupling Capacitors, Lin Zhang, Bruce Archambeault, Samuel Conner, James L. Knighten, Jun Fan, Norman W. Smith, Ray Alexander, Richard E. Dubroff, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A time domain approach to investigate and predict impedances and scattering parameters of a DC power bus is proposed. This approach is based on a cavity model and is achieved using a circuit simulation tool - SPICE. A SPICE-based circuit model for triangular power plane segments is described, verified and applied to simulate both the frequency and time domain characteristics of an irregularly shaped two-layer PCB board. Furthermore, the current draw from a surface mount technology (SMT) decoupling capacitor is simulated and estimated using this approach. Near-field electromagnetic loop probes are used to validate the current estimation qualitatively. Additionally the …


Via Coupling Within Power-Return Plane Structures Considering The Radiation Loss, J. Chen, Todd H. Hubing, Weimin Shi, R. L. Chen Jan 2004

Via Coupling Within Power-Return Plane Structures Considering The Radiation Loss, J. Chen, Todd H. Hubing, Weimin Shi, R. L. Chen

Electrical and Computer Engineering Faculty Research & Creative Works

An accurate analytical model to predict via coupling within rectangular power-return plane structures is developed. Loss mechanisms, including radiation loss, dielectric loss, and conductor loss, are considered. The radiation loss is incorporated into a complex propagating wavenumber as an artificial loss mechanism. The quality factors associated with the three loss mechanisms are calculated and compared. The effects of radiation loss on input impedances and reflection coefficients are investigated for both high-dielectric-loss and low-dielectric-loss PCBs. Measurements are performed to validate the effectiveness of the model.


Radiated Emissions From Populated Printed Circuit Boards Due To Power Bus Noise, Hwan-Woo Shim, Todd H. Hubing, Yan Fu Jan 2004

Radiated Emissions From Populated Printed Circuit Boards Due To Power Bus Noise, Hwan-Woo Shim, Todd H. Hubing, Yan Fu

Electrical and Computer Engineering Faculty Research & Creative Works

Previous studies have demonstrated that power plane pairs in a printed circuit board are capable of generating significant radiated emissions at resonance frequencies if these resonances are not damped by material or component losses. The paper shows that board resonances may be readily damped by component losses. However, radiated emissions from a damped power bus may still exceed FCC or CISPR limits over a broad band of frequencies.


The Development Of A Closed-Form Expression For The Input Impedance Of Power-Return Plane Structures, Minjia Xu, Todd H. Hubing Jan 2003

The Development Of A Closed-Form Expression For The Input Impedance Of Power-Return Plane Structures, Minjia Xu, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

In multilayer printed circuit boards, the noise on the power bus is influenced by the impedance between the power and ground planes. Power-bus noise estimates require an accurate estimate of the power-bus input impedance. This paper develops a closed-form estimate of the input impedance for circular power-return plane structures. When the structure is lossy (e.g., boards employing embedded capacitance or densely populated boards), the energy reflected from the board edge does not significantly affect the input impedance. In general, the expressions developed here for circular structures can be used to estimate the impedance of lossy power-return plane structures of any …


Application Of The Cavity Model To Lossy Power-Return Plane Structures In Printed Circuit Boards, Minjia Xu, Hao Wang, Todd H. Hubing Jan 2003

Application Of The Cavity Model To Lossy Power-Return Plane Structures In Printed Circuit Boards, Minjia Xu, Hao Wang, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

Power-return plane pairs in printed circuit boards are often modeled as resonant cavities. Cavity models can be used to calculate transfer impedance parameters used to predict levels of power bus noise. Techniques for applying the cavity model to lossy printed circuit board geometries rely on a low-loss assumption in their derivations. Boards that have been designed to damp power bus resonances (e.g., boards with embedded capacitance) generally violate this low-loss assumption. This paper investigates the validity of the cavity model when applied to printed circuit board structures where the board resonances are significantly damped. Cavity modeling results for sample lossy …


Printed Circuit Board Emi Source Mechanisms, Todd H. Hubing Jan 2003

Printed Circuit Board Emi Source Mechanisms, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

This tutorial paper reviews the basic mechanisms by which signal voltages and currents on a printed circuit board produce unintentional radiated emissions.


Modeling Noise Coupling From Non-Parallel Pcb Trace Routing, Shaofeng Luan, Fengchao Xiao, W. Liu, Jun Fan, Yoshio Kami, James L. Drewniak, Richard E. Dubroff Aug 2002

Modeling Noise Coupling From Non-Parallel Pcb Trace Routing, Shaofeng Luan, Fengchao Xiao, W. Liu, Jun Fan, Yoshio Kami, James L. Drewniak, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

Coupling between PCB signal traces in proximity is of concern to PCB designers and EMC engineers. The behavior of noise coupling between non-parallel microstrip lines is studied in this paper by a full-wave numerical modeling method CEMPIE, designating a circuit extraction approach based on a mixed-potential integral equation formulation. Good agreement between the numerical results and measurements was obtained.


Eye Pattern Evaluation In High-Speed Digital Systems Analysis By Using Mtl Modeling, Giulio Antonini, James L. Drewniak, Antonio Orlandi, Vittorio Ricchiuti Jul 2002

Eye Pattern Evaluation In High-Speed Digital Systems Analysis By Using Mtl Modeling, Giulio Antonini, James L. Drewniak, Antonio Orlandi, Vittorio Ricchiuti

Electrical and Computer Engineering Faculty Research & Creative Works

A method for simulating the eye pattern of high-speed digital signals propagated on printed circuit boards using multiconductor transmission-line modeling is proposed in this paper. The approach takes into account the frequency-dependent properties of the dielectric materials of the board and of the conductors. The validation is performed by comparing the modeling with measurements taken from the literature, and directly performed on test boards specially design for this study.


Efficient Modeling Of Discontinuities And Dispersive Media In Printed Transmission Lines, R. Araneo, Chen Wang, Xiaoxiong Gu, James L. Drewniak, S. Celozzi Mar 2002

Efficient Modeling Of Discontinuities And Dispersive Media In Printed Transmission Lines, R. Araneo, Chen Wang, Xiaoxiong Gu, James L. Drewniak, S. Celozzi

Electrical and Computer Engineering Faculty Research & Creative Works

The finite-difference time-domain method is applied to the analysis of transmission lines on printed circuit boards. The lossy, dispersive behavior of the dielectric substrate is accurately accounted for by means of several algorithms whose accuracy is discussed and compared. Numerical results are validated by comparisons with measurements and an equivalent circuit of slot in the ground plane is proposed.


Fdtd Modeling Incorporating A Two-Port Network For I/O Line Emi Filtering Design, Xiaoning Ye, James L. Drewniak Feb 2002

Fdtd Modeling Incorporating A Two-Port Network For I/O Line Emi Filtering Design, Xiaoning Ye, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic interference (EMI) filters are often utilized on I/O lines to reduce high-frequency noise form being conducted off the printed circuit board (PCB) and causing EMI problems. The filtering performance is often compromised at high frequencies due to parasitics associated with the filter itself, or the PCB layout and interconnects. Finite difference time domain (FDTD) modeling can be used to quantify the effect of PCB layout and interconnects, as well as filter type, on the EMI performance of I/O line filtering. FDTD modeling of a T-type and π-type filter consisting of surface-mount ferrites and capacitors is considered herein. The FDTD …


Estimating The Power Bus Impedance Of Printed Circuit Boards With Embedded Capacitance, Minjia Xu, Todd H. Hubing Jan 2002

Estimating The Power Bus Impedance Of Printed Circuit Boards With Embedded Capacitance, Minjia Xu, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

Embedded capacitance is an alternative to discrete decoupling capacitors and is achieved by enhancing the natural capacitance between closely spaced power and return planes. This paper employs a simple cavity model to investigate the features affecting the power bus impedance of printed circuit boards with embedded capacitance.


Decoupling Strategies For Printed Circuit Boards Without Power Planes, Todd H. Hubing, Hwan-Woo Shim, Theodore M. Zeeff Jan 2002

Decoupling Strategies For Printed Circuit Boards Without Power Planes, Todd H. Hubing, Hwan-Woo Shim, Theodore M. Zeeff

Electrical and Computer Engineering Faculty Research & Creative Works

Traditional decoupling capacitors connected between V/CC/ and GND traces can be relatively ineffective at frequencies above their self-resonant frequency. This paper evaluates decoupling capacitor mounting strategies on boards without power planes. Techniques for minimizing mutual inductance and improving decoupling at frequencies above resonance are investigated.


Finite-Element Modeling Of Coaxial Cable Feeds And Vias In Power-Bus Structures, Hao Wang, Yun Ji, Todd H. Hubing Jan 2002

Finite-Element Modeling Of Coaxial Cable Feeds And Vias In Power-Bus Structures, Hao Wang, Yun Ji, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents three different models that can be used to represent coaxial cable feeds or vias in printed circuit board power-bus structures. The probe model represents a coaxial feed or via as a current filament with unknown radius. The coaxial-cable model enforces an analytical field distribution at the cable opening or via clearance hole. The strip model employs the equivalent radius concept to represent cylindrical feeds and vias as rectangular strips. Although the strip model is functionally equivalent to two closely positioned probe models, it accurately represents the conductor radius and is more accurate in situations where the via …


On The Interior Resonance Problem When Applying A Hybrid Fem/Mom Approach To Model Printed Circuit Boards, Yun Ji, Todd H. Hubing Jan 2002

On The Interior Resonance Problem When Applying A Hybrid Fem/Mom Approach To Model Printed Circuit Boards, Yun Ji, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

A hybrid finite element method/method of moments (FEM/MoM) technique is used to analyze a printed circuit board power bus structure where the source and observation points are in the near field. The FEM is used to model the lossy region between the planes of the board including the source. The MoM is used to model the region outside the planes and provide a radiation boundary condition to terminate the FEM mesh. Numerical results for a bridged power bus structure are compared with measurements. A nonphysical interior resonance of the electric field integral equation is observed. The problem can be avoided …


Emi Mitigation With Multilayer Power-Bus Stacks And Via Stitching Of Reference Planes, Xiaoning Ye, David M. Hockanson, Min Li, Yong Ren, Wei Cui, James L. Drewniak, Richard E. Dubroff Nov 2001

Emi Mitigation With Multilayer Power-Bus Stacks And Via Stitching Of Reference Planes, Xiaoning Ye, David M. Hockanson, Min Li, Yong Ren, Wei Cui, James L. Drewniak, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

General methods for reducing printed circuit board (PCB) emissions over a broad band of high frequencies are necessary to meet EMI requirements, as processors become faster and more powerful. One mechanism by which EMI can be coupled off a PCB or multichip module (MCM) structure is from high-frequency fringing electric fields on the dc power and reference planes at the substrate periphery An approach for EMI mitigation by stitching multiple ground planes together along the periphery of multilayer PCB power-bus stacks with closely spaced vias is reported and quantified in this paper. Power-bus noise induced EMI and coupling from the …


Dc Power Bus Noise Isolation With Power Islands, Wei Cui, Jun Fan, Hao Shi, James L. Drewniak Aug 2001

Dc Power Bus Noise Isolation With Power Islands, Wei Cui, Jun Fan, Hao Shi, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Segmented power planes are often used for DC power bus noise isolation in multi-layered printed circuit board (PCB) designs. To achieve a desirable noise isolation, different power plane segmentations can be used. A suitable modeling approach, as well as measurements, were employed to study the power bus isolation with several power plane segmentation configurations. The studied geometries included power island designs connected with a conducting bridge, a ferrite bead, and a π-filter. In addition, different conducting bridge widths and power island gap widths were analyzed, and compared. The modeled and measured results show that power plane segmentations with proper designs …