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Full-Text Articles in Engineering
Via Coupling Within Power-Return Plane Structures Considering The Radiation Loss, J. Chen, Todd H. Hubing, Weimin Shi, R. L. Chen
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.
A Preliminary Study Of Maximum System-Level Crosstalk At High Frequencies For Coupled Transmission Lines, H. Weng, Daryl G. Beetner, Todd H. Hubing, R. Wiese, J. Mccallum, Xiaopeng Dong
A Preliminary Study Of Maximum System-Level Crosstalk At High Frequencies For Coupled Transmission Lines, H. Weng, Daryl G. Beetner, Todd H. Hubing, R. Wiese, J. Mccallum, Xiaopeng Dong
Electrical and Computer Engineering Faculty Research & Creative Works
Simple formulas were derived to quickly estimate maximum crosstalk between wires in a harness at high frequencies, where the length of circuits is comparable with or greater than the wavelength of the signals of interest. Formulas were derived from multi-conductor transmission line theory. When the source and load resistances are either both large or both small compared to the characteristic impedance of the transmission line, maximum coupling is shown to be given by approximately XMAX = Cm / (C22 + Cm). A similar equation was found for the case where the load impedances are matched. …
Investigation Of Cavity Resonances In An Automobile, Haixiao Weng, Daryl G. Beetner, Todd H. Hubing, Xiaopeng Dong, Richard W. Wiese, Joseph Mccallum
Investigation Of Cavity Resonances In An Automobile, Haixiao Weng, Daryl G. Beetner, Todd H. Hubing, Xiaopeng Dong, Richard W. Wiese, Joseph Mccallum
Electrical and Computer Engineering Faculty Research & Creative Works
Knowledge of cavity resonance within the automobile is needed to predict electromagnetic crosstalk between circuits in vehicle cavities. To quantify potential cavity resonances, resonance was studied within the passenger compartment of a standard automobile. Measured values of S11, S21 and Q (quality factor) are presented and their effect on crosstalk is discussed. Resonances were found at frequencies from 72 MHz to 303 MHz with quality factors ranging from 4 to 40.
Radiated Emissions From Populated Printed Circuit Boards Due To Power Bus Noise, Hwan-Woo Shim, Todd H. Hubing, Yan Fu
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.
Analysis Of Chip-Level Emi Using Near-Field Magnetic Scanning, Xiaopeng Dong, Shaowei Deng, Todd H. Hubing, Daryl G. Beetner
Analysis Of Chip-Level Emi Using Near-Field Magnetic Scanning, Xiaopeng Dong, Shaowei Deng, Todd H. Hubing, Daryl G. Beetner
Electrical and Computer Engineering Faculty Research & Creative Works
Integrated circuits (ICs) are often a significant source of radiated energy from electronic systems. Well designed ICs maintain good control of the currents that they generate. However, poorly designed ICs can drive high-frequency noise currents onto nominally low-frequency input and output pins. These currents can excite unintentional radiating structures on the printed circuit board, resulting in radiated emissions that are difficult or expensive to control. The paper discusses the use of magnetic near-field scanning techniques to measure the current distribution in IC packages. This technique is applied to common ICs, including a clock driver, a memory module and a field …
Electromagnetic Compatibility Issues In Mobile Computing, Antonio Orlandi, James L. Drewniak
Electromagnetic Compatibility Issues In Mobile Computing, Antonio Orlandi, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
No abstract provided.
Modeling Issues For Full-Wave Numerical Emi Simulation, Michael A. Cracraft, Xiaoning Ye, Chen Wang, Sandeep K. R. Chandra, James L. Drewniak
Modeling Issues For Full-Wave Numerical Emi Simulation, Michael A. Cracraft, Xiaoning Ye, Chen Wang, Sandeep K. R. Chandra, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
In electromagnetic modeling, agreement between modeling and measurements is a common goal. There are questions that define every model. What is to be modeled? How is it going to be modeled? At what scale is it to be modeled? Through sample results and discussion, this paper addresses some general and some specific elements of model veracity. Through determination, numerical models can certainly be pushed to match any measured results. However, in the end the question that this paper addresses is not necessarily "How good can this model be?" as it is "Is this model good enough?".
Memory Dimm Dc Power Distribution Analysis And Design, Jingkun Mao, Chen Wang, Giuseppe Selli, Bruce Archambeault, James L. Drewniak
Memory Dimm Dc Power Distribution Analysis And Design, Jingkun Mao, Chen Wang, Giuseppe Selli, Bruce Archambeault, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
DC power bus design is critical in meeting signal integrity (SI) and electromagnetic compatibility (EMC) requirements. A suitable modeling tool is beneficial to evaluate power bus design and develop design guidelines. This paper discusses difficulties met in evaluating the power distribution design on a dual inline memory module (DIMM) board, such as a power bus with arbitrary shape, parasitic inductance associated with vias, and so on. Moreover, some solutions are given in this paper. A simple cavity model with a segmentation method was employed to model a power bus with irregular shapes. The partial element equivalent circuit (PEEC) technique was …
Dc Power-Bus Noise Isolation With Power-Plane Segmentation, Wei Cui, Jun Fan, Yong Ren, Hao Shi, James L. Drewniak, Richard E. Dubroff
Dc Power-Bus Noise Isolation With Power-Plane Segmentation, Wei Cui, Jun Fan, Yong Ren, Hao Shi, James L. Drewniak, Richard E. Dubroff
Electrical and Computer Engineering Faculty Research & Creative Works
Power-plane segmentation is often used for DC power-bus noise isolation in multilayer 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 in this work to study the noise isolation with several power-plane segmentation designs. The geometries studied include power islands, and totally segmented power planes. The effects of the power-bus noise isolation with different types of power island connections, locations of segmentation, and shapes were analyzed, and compared. The modeled and measured results show that suitable power-plane segmentation can result in significant …
Foreword Advanced Emc Numerical Modeling, Christos Christopoulos, James L. Drewniak
Foreword Advanced Emc Numerical Modeling, Christos Christopoulos, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
No abstract provided.
A Dual-Current Method For Characterizing Common-Mode Loop Impedance, Geping Liu, Yimin Ding, Chingchi Chen, Richard W. Kautz, James L. Drewniak, David Pommerenke, Marina Koledintseva
A Dual-Current Method For Characterizing Common-Mode Loop Impedance, Geping Liu, Yimin Ding, Chingchi Chen, Richard W. Kautz, James L. Drewniak, David Pommerenke, Marina Koledintseva
Electrical and Computer Engineering Faculty Research & Creative Works
The definition of common-mode loop impedance is proposed instead of the ambiguous definition of common-mode impedance. Moreover, a non-invasive measurement method to characterize the common-mode loop impedance using dual clamp-on current probe is presented herein. The frequency responses of the current probes are de-embedded through a calibration procedure. Independent direct measurements using a network analyzer corroborate the validity of the Dual-Current-Probe Method.
Numerical Modeling Of Electrostatic Discharge Generators, Kai Wang, David Pommerenke, Ramachandran Chundru, Thomas Van Doren, James L. Drewniak, A. Shashindranath
Numerical Modeling Of Electrostatic Discharge Generators, Kai Wang, David Pommerenke, Ramachandran Chundru, Thomas Van Doren, James L. Drewniak, A. Shashindranath
Electrical and Computer Engineering Faculty Research & Creative Works
The discharge current and the transient fields of an electrostatic discharge (ESD) generator in the contact mode are numerically simulated using the finite-difference time-domain method. At first the static field is established. Then the conductivity of the relay contact is changed, which initiates the discharge process. The simulated data are used to study the effect of design choices on the current and fields. They are compared to measured field and current data using multidecade broadband field and current sensors. The model allows accurate prediction of the fields and currents of ESD generators, thus it can be used to evaluate different …
Power-Bus Decoupling With Embedded Capacitance In Printed Circuit Board Design, Minjia Xu, Todd H. Hubing, Juan Chen, Thomas Van Doren, James L. Drewniak, Richard E. Dubroff
Power-Bus Decoupling With Embedded Capacitance In Printed Circuit Board Design, Minjia Xu, Todd H. Hubing, Juan Chen, Thomas Van Doren, James L. Drewniak, Richard E. Dubroff
Electrical and Computer Engineering Faculty Research & Creative Works
This paper experimentally investigates the effectiveness of embedded capacitance for reducing power-bus noise in high-speed printed circuit board designs. Boards with embedded capacitance employ closely spaced power-return plane pairs separated by a thin layer of dielectric material. In this paper, test boards with four embedded capacitance materials are evaluated. Power-bus input impedance measurements and power-bus noise measurements are presented for boards with various dimensions and layer stack ups. Unlike discrete decoupling capacitors, whose effective frequency range is generally limited to a few hundred megahertz due to interconnect inductance, embedded capacitance was found to efficiently reduce power-bus noise over the entire …
Printed Circuit Board Emi Source Mechanisms, Todd H. Hubing
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.
Impedance Boundary Conditions In A Hybrid Fem/Mom Formulation, Hao Wang, Minjia Xu, Chen Wang, Todd H. Hubing
Impedance Boundary Conditions In A Hybrid Fem/Mom Formulation, Hao Wang, Minjia Xu, Chen Wang, Todd H. Hubing
Electrical and Computer Engineering Faculty Research & Creative Works
When numerically modeling structures with imperfect conductors or conductors coated with a dielectric material, impedance boundary conditions (IBCs) can substantially reduce the amount of computation required. This paper incorporates the IBC in the finite-element method (FEM) part of a FEM/method of moments (FEM/MoM) modeling code. Properties of the new formulation are investigated and the formulation is used to model three practical electromagnetic problems. Results are compared to either measured data or other numerical results. The effect of the IBC on the condition number of hybrid FEM/MoM matrices is also discussed.
A Study Of The Probe Induced Disturbances On The Near-Field Measurement, Jin Shi, Richard E. Dubroff, Kevin P. Slattery, Masahiro Yamaguchi, K.-I. Arai
A Study Of The Probe Induced Disturbances On The Near-Field Measurement, Jin Shi, Richard E. Dubroff, Kevin P. Slattery, Masahiro Yamaguchi, K.-I. Arai
Electrical and Computer Engineering Faculty Research & Creative Works
Numerical simulations were used to investigate the disturbance introduced by placing a small magnetic loop probe in the near field of a driven loop. In the absence of the loop probe, the numerical simulations were compared with an approximate closed-form analytical expression for the magnetic field produced by the driven loop. The agreement between the approximate analytical results and the simulation was good. The next set of simulations was based on a physical model that included the probe and showed that the probe does exert an effect on the field being measured. Examples of these simulations and their implications on …
Pcb Emc Design Guidelines: A Brief Annotated List, Todd H. Hubing
Pcb Emc Design Guidelines: A Brief Annotated List, Todd H. Hubing
Electrical and Computer Engineering Faculty Research & Creative Works
Some of the worst printed circuit board design choices are made by engineers who are trying to comply with a list of EMC design guidelines. Nevertheless, a short list of design guidelines can be helpful at times. This paper reviews some of the more general EMC design guidelines for printed circuit board layout.
Analysis Of Simple Two-Capacitor Low-Pass Filters, Todd H. Hubing, David Pommerenke, Theodore M. Zeeff, Thomas Van Doren
Analysis Of Simple Two-Capacitor Low-Pass Filters, Todd H. Hubing, David Pommerenke, Theodore M. Zeeff, Thomas Van Doren
Electrical and Computer Engineering Faculty Research & Creative Works
The performance of typical low-pass capacitor filters is limited by the mutual inductance between the input and output sides of the filter. This paper describes how two appropriately spaced capacitors can be used to construct a low-pass filter with significantly better high-frequency performance than a one-capacitor filter. Laboratory measurements and numerical simulations are used to quantify the mutual inductance and compare the performance of one- and two-capacitor low-pass filters.
Estimating Dc Power Bus Noise, Jingkun Mao, Bruce Archambeault, James L. Drewniak, Thomas Van Doren
Estimating Dc Power Bus Noise, Jingkun Mao, Bruce Archambeault, James L. Drewniak, Thomas Van Doren
Electrical and Computer Engineering Faculty Research & Creative Works
Simultaneous switching noise (SSN) resulting from IC devices can result in significant power bus noise, as well as radiation problems. An approach for estimating the power bus noise spectrum is presented in this paper. The power bus noise caused by digital circuits injecting high-frequency noise onto the DC buses feeding digital devices is calculated. The transient current drawn by an IC device is modeled using the load current and the shoot-through current through the power dissipation capacitance. Modeling and experimental results for several digital chips are shown. The modeling agrees well with the experimental results.
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
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.
Anticipating Full Vehicle Radiated Emi From Module-Level Testing In Automobiles, Geping Liu, Chingchi Chen, Yuhua Tu, James L. Drewniak
Anticipating Full Vehicle Radiated Emi From Module-Level Testing In Automobiles, Geping Liu, Chingchi Chen, Yuhua Tu, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
EMI due to common-mode currents on cables routed in automobiles was studied using a test device designed to mimic a vehicle. Both experimental work and Finite-Difference Time-Domain (FDTD) modeling were employed in this paper. The good agreement between the measurements and modeling results indicates that the numerical tools can be a useful aid in predicting vehicle-level EMI by developing vehicle transfer functions and measuring the module-level EMI characteristics on the bench top.
Field Extraction From Near Field Scanning For A Microstrip Structure, Lin Zhang, Kevin P. Slattery, Chen Wang, Masahiro Yamaguchi, K.-I. Arai, Richard E. Dubroff, James L. Drewniak, David Pommerenke, Todd H. Hubing
Field Extraction From Near Field Scanning For A Microstrip Structure, Lin Zhang, Kevin P. Slattery, Chen Wang, Masahiro Yamaguchi, K.-I. Arai, Richard E. Dubroff, James L. Drewniak, David Pommerenke, Todd H. Hubing
Electrical and Computer Engineering Faculty Research & Creative Works
Currents associated with high-speed digital devices have significant impacts on EMI problems in VLSI design and operation. In this paper, a simple transmission line model was implemented as an initial step to represent the EMI mechanisms associated with an IC package. Numerical modeling results were compared with near field scanning measurements and show that the magnetic field deduced from the measurements agrees well with the numerical predictions.
Alternatives To Gaskets In Shielding An Enclosure, Federico Centola, David Pommerenke, James L. Drewniak, Xiao Kai
Alternatives To Gaskets In Shielding An Enclosure, Federico Centola, David Pommerenke, James L. Drewniak, Xiao Kai
Electrical and Computer Engineering Faculty Research & Creative Works
It is well known that a properly placed conductive gasket can complete an enclosure to yield good shielding. But often there are reasons, e.g. control of mechanical dimensions that this cannot be achieved. For these cases, one may want to avoid using a gasket that requires contacts. This paper will analyze alternatives to continuously contacting gaskets such as overlap structures, overlapping structures with different lossy and non-lossy materials, and overlaps with grounding points. It will compare structures by sufficient shielding for a typical class B product, high frequency (1-3 GHz) and low frequency (below 1 GHz) performance.
Fdtd Modeling Of Skin Effect, Chen Wang, James L. Drewniak, Min Li, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, Jingyu Huang
Fdtd Modeling Of Skin Effect, Chen Wang, James L. Drewniak, Min Li, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, Jingyu Huang
Electrical and Computer Engineering Faculty Research & Creative Works
The data rates and clock speeds of current highspeed signals are increasing rapidly, consequently, not only the lossy nature of FR-4 but also the lossy nature of good conductors, such as copper, need to be taken into account in high-speed signal designs. In order to well predict the loss caused by both dielectric loss and skin effect loss, a suitable simulation tool is needed. A surface impedance boundary condition (SIBC) algorithm was implemented in FDTD modeling herein to accommodate the skin effect loss due to finite conductivity of good conductors. Good agreement between the FDTD result and the measurements as …
Estimating The Noise Mitigation Effect Of Local Decoupling In Printed Circuit Boards, Jun Fan, Wei Cui, James L. Drewniak, Thomas Van Doren, James L. Knighten
Estimating The Noise Mitigation Effect Of Local Decoupling In Printed Circuit Boards, Jun Fan, Wei Cui, James L. Drewniak, Thomas Van Doren, James L. Knighten
Electrical and Computer Engineering Faculty Research & Creative Works
Local decoupling, i.e., placing decoupling capacitors sufficiently close to device power/ground pins in order to decrease the impedance of power bus at frequencies higher than the series resonant frequency, has been studied using a modeling approach, a hybrid lumped/distributed circuit model established and an expression to quantify the benefits of power bus noise mitigation due to local decoupling developed. In this work, a test board with a local decoupling capacitor was studied and the noise mitigation effect due to the capacitor placed adjacent to an input test port was measured. Closed-form expressions for self and mutual inductances of vias are …
An Expert System Architecture To Detect System-Level Automotive Emc Problems, Sreeniwas Ranganathan, Daryl G. Beetner, R. Wiese, Todd H. Hubing
An Expert System Architecture To Detect System-Level Automotive Emc Problems, Sreeniwas Ranganathan, Daryl G. Beetner, R. Wiese, Todd H. Hubing
Electrical and Computer Engineering Faculty Research & Creative Works
Improving EMC in automobiles requires methods to detect potential problems early in the design process. Issues involved in the development of a system-level automotive EMC expert system are explored. The proposed system would help identify problems with radiation and immunity, crosstalk, placement of modules, component grounding and EMC testing. The architecture of the expert system has been developed. The system architecture is designed to allow rapid analysis of automobile designs, to point out potential problems and to suggest possible solutions.
Quantifying Smt Decoupling Capacitor Placement In Dc Power-Bus Design For Multilayer Pcbs, Jun Fan, James L. Drewniak, James L. Knighten, Norman W. Smith, Antonio Orlandi, Thomas Van Doren, Todd H. Hubing, Richard E. Dubroff
Quantifying Smt Decoupling Capacitor Placement In Dc Power-Bus Design For Multilayer Pcbs, Jun Fan, James L. Drewniak, James L. Knighten, Norman W. Smith, Antonio Orlandi, Thomas Van Doren, Todd H. Hubing, Richard E. Dubroff
Electrical and Computer Engineering Faculty Research & Creative Works
Noise on a dc power-bus that results from device switching, as well as other potential mechanisms, is a primary source of many signal integrity (SI) and electromagnetic interference (EMI) problems. Surface mount technology (SMT) decoupling capacitors are commonly used to mitigate this power-bus noise. A critical design issue associated with this common practice in high-speed digital designs is placement of the capacitors with respect to the integrated circuits (ICs). Local decoupling, namely, placing SMT capacitors in proximity to ICs, is investigated in this study. Multilayer PCB designs that employ entire layers or area fills for power and ground in a …
Representation Of Gyromagnetic Composite Media For Fdtd Modeling, Marina Koledintseva, James L. Drewniak, Xiaoning Ye
Representation Of Gyromagnetic Composite Media For Fdtd Modeling, Marina Koledintseva, James L. Drewniak, Xiaoning Ye
Electrical and Computer Engineering Faculty Research & Creative Works
A composite media containing particles with a high internal field of magnetic anisotropy (hexagonal ferrites) useful for numerous EMC applications in a wide frequency band is considered. Effective constitutive parameters of a high-loss composite gyromagnetic media are represented in the Lorentzian form. It is convenient for the numerical analysis using the finite-difference time-domain (FDTD) algorithm with a recursive convolution procedure. The equations for the electric and magnetic field updating in such media are represented.
Including Smt Ferrite Beads In Dc Power Bus And High-Speed I/O Line Modeling, Jun Fan, Shaofeng Luan, James L. Drewniak
Including Smt Ferrite Beads In Dc Power Bus And High-Speed I/O Line Modeling, Jun Fan, Shaofeng Luan, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
Surface mount technology (SMT) ferrite beads are often used in high-speed digital circuit designs to mitigate noise. The common modeling approach is to include SMT ferrite beads as equivalent lumped LCR circuits. The work presented in this paper included SMT ferrite beads as a frequency-dependent impedance in a PEEC-like modeling tool denoted CEMPIE, a circuit extraction approach based on a mixed-potential integral equation formulation. Agreement with measurements demonstrates the approach. The applications shown are segmentation of power areas for noise isolation, and I/O line filtering.
Mitigating Power Bus Noise With Embedded Capacitance In Pcb Designs, Minjia Xu, Todd H. Hubing, Juan Chen, James L. Drewniak, Thomas Van Doren, Richard E. Dubroff
Mitigating Power Bus Noise With Embedded Capacitance In Pcb Designs, Minjia Xu, Todd H. Hubing, Juan Chen, James L. Drewniak, Thomas Van Doren, Richard E. Dubroff
Electrical and Computer Engineering Faculty Research & Creative Works
This paper investigates the power bus noise and power bus impedance of printed circuit boards with four different kinds of embedded capacitance. These boards have power-ground plane pairs separated by a very thin layer of material with high dielectric permittivity. It is shown that embedded capacitance effectively reduces power bus noise over the entire frequency range evaluated (up to 5 GHz).