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International audience; Transfer impedance of shielded cables is a main characteristic to describe cable shielding performance at least up to 1 GHz. Traditionally, a cable shield consists of a braid, a foil, or a combination of them. Braids have attracted a significant amount of research interest, while foils have not. Published studies have concentrated on cable shielding performance when cables are new. In this paper, a highly accelerated aging method for shielded cables is presented and applied to a cable made up of a combination of a braid and foil shield. Finally, the effect of aging on system performance during bulk current injection (BCI) tests is assessed by circuit simulation.

International audience; Shielded cables are an important mitigation for electromagnetic interference (EMI) in high-speed data systems. In the automotive domain, one use for them is to transmit image data from a front camera to an advanced driver assistance system (ADAS) controller. Some ADAS functions have implication for human safety and thus place extra requirements for the design of the transmission path including its resilience to EMI. This paper presents a case study of an automated lane centering (ALC) system with the above-mentioned shielded cable use case. The study starts from a National Highway Traffic Safety Administration (NHTSA) concept level assessment. Subsystem components are then separated and a physical realization derived. Goal Structuring Notation (GSN) is used to present EMI assurance scenarios over the safety requirements. First, the ability of a shielded cable reliability argument to cover the derived safety requirements during different operating scenarios is studied. It is found that relying on reliability alone, it is challenging to fulfil all the safety requirements. To overcome this challenge, an alternative systems safety based method is studied.

International audience; Triaxial measurement is an effective means to determine the transfer impedance of a shielded cable. It is based on coupled transmission line principle. In an ideal case, both transmission lines in the setup would be matched to guarantee the high frequency performance. In practice, matching is hard to achieve without compromising on usability and generality of the measurement setup. This paper discusses how triaxial cell diameter and the resulting impedance mismatch affects transfer impedance measurement results. In addition, the paper shows how impedance mismatches can be modeled, presents a simplified model to quickly understand the effects of impedance mismatch, and compares the model to results measured with different triaxial cell sizes. The simple model presented achieved similar accuracy to a more complex model defined in IEC 62153.

Designing of low-cost and more compact electromagnetic interference (EMI) filters must be achieved by considering intercomponent coupling. Actually, magnetic coupling, arising from the proximity of the components constituting the filter, has a major influence on the filter performance. The aim of this paper is to present a methodology for filter design, which takes into account intercomponent coupling and, therefore, can predict filter attenuation very accurately, whatever the structure and the topology of the filter may be.

International audience; ElectroMagnetic Interference (EMI) simulation of power converters helps engineers in the design process. In this paper, we describe a frequency-domain simulation method based on the Multi-Topology Equivalent Sources (MTES) model. The aim is to reproduce the non-linear behavior of power switches for a fast evaluation of the conducted EMI. The method performance is validated on a DC-DC converter.

This article presents a comprehensive study of the influence of electromagnetic (EM) field polarization on radiated emission characterization in an open transverse EM (TEM) cell, which is usually neither considered in the measurement process nor clearly identified. It also takes into account the influence of the operating frequency with respect to the higher order mode cutoff frequency of the cell, the latter being generally unknown to the experimenter. Commonly used 433-MHz (LoRa) and 2.4-GHz (Wi-Fi) antennas were placed inside an open TEM cell in different orientations in order to investigate the impact of the antenna polarization. For antennas parallel to the septum, a 1.6–8.6-dB difference in power levels collected by the cell (corresponding to a 31%–86% underestimation), for different polarizations, depending on the operating frequency being below or above the higher order mode cutoff frequency, was obtained between orthogonal orientations due to reduction in $E$ - and (mainly) $H$ -field levels, leading to significant uncertainty on power levels. For the 2.4-GHz antenna perpendicular to the septum, the power level was highly dependent on both the antenna orientation and location along the cell’s axes, being more dependent along the main axis. This clearly demonstrates that the physical phenomena due to the polarization of the radiating element and the cell’s dominant mode frequency must be characterized and estimated, in addition to the generally known tangential $H$ -field coupling to integrated circuit pins or printed circuit board (PCB) traces. This leads to an update of best practices of IEC 61000-4-20 or IEC 61967-2 emission testing.

CISPR25 is the reference standard in the automotive industry for performing radiated emissions measurements in a semi-anechoic chamber. Significant differences can be observed between different CISPR25-compliant laboratories when measuring emissions on the same device under test. In this paper, these differences are evaluated through an interlaboratory comparison across 17 laboratories, with a special focus on the 30−100 MHz frequency range. The aim of this paper is to identify what the parameters (corresponding to degrees of freedom in the standard) leading to these observations are. A three-dimensional (3-D) model of the semi-anechoic chamber is built and validated to analyze the influence of each of these parameters individually. Recommendations are finally established to minimize the variation observed between laboratories.

The design of cheaper and more compact electromagnetic compatibility (EMC) filters can be achieved by exploiting the magnetic coupling between components. This requires the knowledge of coupling coefficients between components and, consequently, of their equivalent coupling surface. The aim of this paper is to present how this coupling surface can be determined using a transverse electromagnetic mode cell. This methodology is described and applied to two different cases: a capacitor and an inductor. In order to validate the determination and usage of equivalent coupling surfaces, a comparison between the calculation and measurement of mutual inductances is carried out on practical examples.

Filter design heavily depends on magnetic inter-component couplings. To determine the magnetic coupling, i.e. the mutual inductance between two components, it is necessary to define a coupling model, in order to figure out to which extent a component catches the magnetic field. The coupling model of complex components, such as common mode chokes, cannot be established directly from geometry because of the number of ports, the possible modes (common and differential) and the magnetic material. This paper presents a procedure to determine the coupling model of common mode chokes using a TEM (Transverse ElectroMagnetic) cell.

A based-on-measurement approach to extract the SPICE model of MOSFETs accurately is presented in this paper. The main idea of this approach is to adjust the MOSFET waveforms obtained from simulation to those from measurement by modifying the component's internal parameters. Thanks to a parametric study which identifies the influence level of each MOSFET parameter on each zone of the MOSFET waveforms, the correlation procedure becomes intuitive and easy. Moreover, a Matlab-based tool with interaction with Simetrix (an electrical circuit simulator) has been developed to display in real-time the comparison between simulation and measurement waveforms of the MOSFET under test and provide the instruction about the parameter to be modified. The SPICE model extracted from this tool contains reliable values of MOSFET parasitic elements. Therefore, it is suitable to be used in EMC simulations in order to predict the levels of conducted emissions of a product/system containing the component. A good coherence up to 10 MHz was obtained between simulation and measurement.

This study is a result of a close partnership between a car manufacturer and an automotive component supplier. The aim is to develop electromagnetic compatibility models, i.e., immunity models to predict real-world system failure conditions that can occur inside a vehicle. For the study, we selected an interface that manages air-conditioning inside a vehicle recently put on the market. The system model is submitted by an equipment supplier as a compilation of input impedances and threshold transmitted powers causing a malfunction. The predefined model is then used by a car manufacturer on vehicle-level electromagnetic compatibility simulation, by taking into account the harness configuration and the system placement inside the vehicle cab and chassis. In this paper, we detail the complete method and demonstrate its validity.

International audience; In filter design, inter-component parasitic couplings play a major role in the filter response. Most often, filter designers try to minimize these couplings through a proper implementation of components; conversely, this paper aims to optimize filter responses through a clever use of these couplings. Previous works have been performed to reach such an objective ([1]-[2]), focusing on the study of LC filters with 3D simulation or PSpice techniques. Moreover, the MKME method has been identified as a promising technique in many design cases. The objective of this paper is to introduce the application of the MKME method to an LC filter, to validate its use and benefits, before deploying it for more complex filter structures.

International audience; In this paper, the signal integrity (SI) and Electromagnetic Compatibility (EMC) performance of System-On-Chip (SoC) and stacked memory using Package-On-Package (PoP) technology is investigated. The reconfiguration of the IC-EMC software platform to PoP is described. From an existing 2D assembly using a discrete 65-nm SoC product, the benefits of PoP integration using a next-generation 28-nm product with stacked memory are analyzed, based on simulation and predictive analysis performed using IC-EMC software platform.

International audience; A new international standard proposal (IEC 62433-2 Edition 2.0) is in progress. The main purpose of the standard is to provide an Integrated Circuit Emission Model – Conducted Emission (ICEM-CE) along with a data exchange format. It is known that the existing ICEM-CE information is closely linked to the supplier of the model or simulation software used to generate the model information, rendering extremely difficult its exchange between suppliers, customers, EDA tool vendors, academics, etc. This paper describes a universal exchange format for ICEM-CE. The format is based on the well-known eXtensible Markup Language format, which is both machine and human readable. As an illustrative example, it is applied on an Atmega88 microcontroller: the model is extracted by the manufacturer, Atmel, and is exchanged with an academic partner, INSA, and an industrial partner, Valeo. The exchange proves fruitful and the model was easily deployable to predict conducted emission noise.

In order to perform EMC design activities, engineers need to have some tools for preliminary risk analysis to determine filters needs and/or architecture orientation choices. Huge variations in term of requirements between different carmakers can be observed (40 dB difference for example for a simple conducted emission test can be observed between OEMs). The product nature that we develop can be also very different (from small cameras to DC/DC converter for Electric Vehicle applications). As a consequence we decided to develop simulation capabilities based on Pspice, instead of using generic rules or simple return on experiences to design our products. This paper provides a synthesis of these capabilities, for emission, immunity and ESD testing, focusing on the latest modeling techniques developed for these different aspects.

As electromagnetic compatibility (EMC) gains ground in today's world of electronics, integrated circuit (IC) and printed circuit board (PCB) modelling methods are of paramount importance during development of EMC compliant products. One such aspect focuses on modelling the emissions from ICs and PCBs, both conducted and radiated forms. This work proposes a method for modelling the radiated emissions of ICs (PCBs, …) from near-field data. It also describes a universal exchange format for representing and sharing the model data between industrials, academics and EDA simulation tools.

International audience; In this paper, a methodology to calculate the shielding effectiveness (SE) of enclosures with slots at low frequency in the near magnetic field is presented. This modeling technique is based on the magnetic moments and the transmission line (TL) approach and makes specific assumptions. It is applied to a slot of small size relative to the dimensions of the enclosure. The slot is electrically short. This technique is validated in the case of a real enclosure with numerical simulations and experimental data. This method is dedicated to the case of mechatronics boxes using in electric and hybrid vehicles (EHVs), it allows obtaining the results with sufficient accuracy precision for dimensioning a magnetic shielding in a short time.

The purpose of this paper is to present the results obtained with a gigahertz transverse electromagnetic mode (GTEM) cell for each phase of the project development, which consists of measuring and quantifying the integrated circuit's emissions and immunity compliance with automotive standards. These standards are defined using half anechoic chambers (HAC). Studies have already been conducted to compare trans electromagnetic (TEM) cell and HAC, or far-field emissions, and the test results show a limited correlation between TEM cells and the free space field or HAC. In this paper, it is shown that the correlation between the measurements made in a GTEM cell and HAC can be good enough in allowing us to use the GTEM facility during the research and development (R&D) phase (considering the facts that the HAC facility is often quite overloaded and of a high cost), that knowledge of the electromagnetic compatibility behavior of the integrated circuit is important for predicting the whole system's results as well as how to use an integrated circuit electromagnetic model to make the prediction of emissions.

This paper proposes a complete flow to model the radiated emissions (RE) of electronic components, board and equipments from near-field measurements. A precise RE model needs accurate vector field (amplitude and phase) information, but obtaining the same is not always straightforward. A novel method to measure the vector near-field data using the near-field scan (NFS) technique is first presented. The measurement technique extends the limitations of the existing NFS practices to provide an accurate and stable magnitude and phase information of the fields of arbitrary printed circuit boards (PCBs). The measured vector field-data is then used as input for modelling the RE of the equipment under test with the use of elementary electric and/or magnetic dipoles. The modelling philosophy, from measurements to model construction, is presented and validated on a LED turn-lights developed by Valeo.

CISPR25 [1] is the reference standard for EMI characterization of automotive equipments. This standard specifies major requirements regarding the semi anechoic chamber characteristics, such as its size, the ground plane minimum size, the ground connection to the Faraday cage quality, the absorbers' minimum performances… Nevertheless the degrees of freedom afforded in this standard for these particular parameters are identified as key factors leading to significant deviations in results obtained on emissions measurement performed on equipments between “CISPR25 compliant chambers”. This paper highlights these effects and try to provide some analysis and proposals in order to get a better management of testing results between labs.

LGEP 2014 ID = 1556; International audience; Equipment used in hybrid or electric vehicles (HEVs) must meet certain requirements. Beyond issues of electro-magnetic compatibility (EMC), it's necessary to assess the risks related to the exposure of the passengers to electromagnetic field inside an HEV. At low frequencies, using the electromagnetic shielding as protection is inefficient. The compliance can be achieved done by defining the harness's architecture or by the use of permeable materials. In this paper, we will focus on the prediction of the shielding effectiveness of materials subjected to a near magnetic field source at low frequency (9 kHz-10 MHz).We will focus our study on two cases. In the first case, we will work on the numerical modeling of an enclosure with and without opening. The result from the model is compared to the measurement's results obtained with a test bench developed in our laboratory. In the second case, the impact of the slot in the enclosure will be studied. An analytical method based on magnetic moments approximation is developed to predict the shielding effectiveness for infinite plane with slot. The results obtained with the latter are compared with the numerical results.

Electrostatic Discharge (ESD) is a major constraint for electronic product design and especially in automotive domain, where requirements can reach levels up to 25 kV. The reference standard cited in most of carmakers specification is the ISO 10605 [1]. Historically product design was mainly based on experience and experiments, but recent works started to develop modeling and simulation capabilities to justify the design, such as [2,3,4]. These approaches consist in black box modeling techniques based on characteristics extracted on the device to be modeled. Without demonstrated link with the physics, these modeling techniques are nevertheless the only acceptable and efficient method for concrete industrial deployment. The practical implementation of these Integrated Circuit (IC) models induced some issues, especially under Pspice being the targeted tool for our simulation. Divergences issues frequently occur during time domain simulation and were irresolvable with model proposed in [4]. We propose in this article a new implementation of the model in Pspice, as well as an updated general approach for black box model definition and generation. A practical example is used to demonstrate the capability of our model.

International audience; In this paper, we present a modeling methodology for the prediction of the magnetic shielding effectiveness in the near field at low frequencies. This study shows an analytical method which is based on magnetic moments approximations to predict the shield effectiveness for infinite plane with narrow slot. The results obtained with the proposed method are compared with the numerical results.

International audience; The direct power injection (DPI) test defined in IEC 62132-4 measures the conducted immunity of integrated circuits (ICs) up to 1GHz. As the frequency of functional and interference signals is increasing, we would like to characterise immunity for higher frequencies as well. In this paper, we show why typical IEC 62132-4 compliant DPI set-ups become inaccurate when going up to 20GHz. We propose to determine the power Ptrans actually transmitted to the device under test (DUT) by using offline short-open-load-thru (SOLT) or thru-reflect-line (TRL) calibration. Furthermore, we design a low-cost FR4 printed circuit board (PCB) that allows for testing of SOIC8-packaged ICs. We verify that this board has acceptable and reproducible losses up to 20 GHz, as well as acceptable crosstalk.

L’objectif de cet article est de presenter un etat de l’art sur la methodologie de developpement CEM. Apres un rappel du cycle de developpement en V, nous decrivons les etapes de l’approche remontante qui vont permettre de justifier les specifications de design. Les regles de l’art permettent d’eviter les erreurs majeures de design, cependant les contraintes mecaniques, thermiques ou de placement rendent inapplicables certaines regles. Il faut donc specifiquement les adapter et les justifier par modelisation. La derniere etape du developpement est la redaction du Plan de Test qui va permettre de garantir la reproductibilite des resultats.

Conducted disturbances induced into automotive electronic equipment can be predicted in the early design phase by numerical simulation. This supposes a realistic modeling of the cable harness, as well as the electronic equipment. This paper evaluates a modeling method by the results obtained on a realistic automotive subsystem. The latter is composed of two pieces of electronic equipment connected to each other by a cable harness. This test case was performed on printed circuit boards (PCBs) with full or partial ground planes and using a representative sample of harnesses. Simulation results are compared with measurement results using multiple cable harness samples. A good agreement between measurement and simulation can be obtained for PCBs with full ground plane, provided that fringing effects of the electronic components are taken into account in the equipment model.

WOS; International audience; This paper introduces a new technique for electromagnetic immunity modeling of integrated circuits (ICs), compliant with industrial requirements and valid up to 3 GHz. A specific modeling flow is introduced, which makes it possible to predict the conducted immunity of an IC according to a given criterion, whatever its external environment. This methodology was validated through measurements performed on several devices.

This paper presents a novel technique for modeling the electrostatic discharge snapback phenomenon in integrated circuits (ICs). The macromodel is built using standard components: BSIM3v3.2 model for the MOSFET, a bipolar transistor modeled by Mextram 504.7, and a substrate resistor. The IC under test is characterized by its die and package impedance. The model should allow easier simulation program with IC emphasis implementation, high simulation speed, less convergence issues, and wider availability of a gate-grounded n-type MOSFET protection device. Our model determines the interaction between the protection device and the internal circuitry of the IC. The model parameters are extracted with MATLAB script. Simulation results are compared with transmission-line pulsing measurement for a voltage regulator NCV4949 and a controller area network transceiver TLE6250G.

Near-field scan measurements and simulations generate a large amount of data. The format of the data is closely linked to the supplier of the acquisition or simulation software, rendering extremely difficult its exchange between suppliers, customers, EDA tool vendors, academics, etc. The paper describes how a universal exchange format for near-field scan data has been developed. The format caters for various coordinate systems and is suited to emission and immunity testing both in the frequency and time domains.

In order to design electronic products for Electro Static Discharges constraints, the use of simulation is fundamental. This is the only solution to justify the design and to manage properly the margin during the development. In order to do so, models are required and especially for the integrated circuits (IC). A Pspice model had been developed and validated for ESD performance prediction of IC implemented inside an electronic product. Nevertheless, the practical implementation of these modeling techniques for IC induced some issues, especially under Pspice, being the targeted tool for our simulation. Divergences issues during time domain simulation were frequently observed and sometimes irresolvable with model previously proposed. We propose in this article new implementation techniques in Pspice. A practical example is used to demonstrate the capability of our model.

The paper shows a near field scanning method to characterize chips that leads to the prediction of the coupling phenomena on the electronic board and to the evaluation of the radiated emission at one meter. A theoretical model is first given for simple circuits. An estimation of the scalar and vector potentials is found with the EM scan. Using these results, we calculate the near and far emissions. Comparisons with experimental results are given. As a conclusion, we propose a simple model describing chip radiated emission and we show a real case use