Abstract-To obtain Electromagnetic Compatibility (EMC), we would like to study the worst-case electromagnetic field-induced voltages at the ends of Printed Circuit Board (PCB) traces. With increasing frequencies, modelling these traces as electrically short no longer suffices. Accurate long line models exist, but are too complicated to easily induce the worst case. Therefore, we need a simple analytical model. In this article, we predict the terminal voltages of an electrically long, two-wire transmission line with characteristic loads in vacuum, excited by a linearly polarised plane wave. The model consists of a short line model (one Taylor cell) with an intuitive correction factor for long line effects: the modified Taylor cell. We then adapt the model to the case of a PCB trace above a ground plane, illuminated by a grazing, vertically polarised wave. For this case, we prove that end-fire illumination constitutes the worst case. We derive the worst-case envelope and try to falsify it by measurement in a Gigahertz Transverse Electromagnetic (GTEM) cell.

This paper introduces a complete simulation model of a Direct Power Injection (DPI) setup, used to measure the immunity of integrated circuits to conducted continuous-wave interference. This model encompasses the whole measurement setup itself as well as the integrated circuit under test and its environment (printed circuit board, power supply). Furthermore, power losses are theoretically computed, and the most significant ones are included in the model. Therefore, the injected power level causing a malfunction of an integrated circuit, according to a given criterion, can be identified and predicted at any frequency up to 1 GHz. In addition to that, the relationship between immunity and impedance is illustrated. Simulation results obtained from the model are compared to measurement results and demonstrate the validity of this approach.

No abstract

No abstract

No abstract

The performance of two oscillator circuits, namely a current-starved voltage controlled oscillator and a ring oscillator, is compared with respect to multi-tone direct power injection (DPI). The objective is to investigate the impact of causal dependence between multi-tones on the immunity levels of integrated blocks with different architectures but similar functionality. The multi-tone immunity analysis performed using the probabilistic noisy-OR model reveals an increase in the probability of failure due to electromagnetic interference relatively to single-tone EM disturbance. The proportions of inhibition and positive causality, as well as the mean degree of synergy (DoS) caused by multi-tone EM disturbances, are extensively compared for both oscillator circuits.

This paper proposes a novel simple cost-effective technique to improve the potential immunity of integrated circuits (ICs) to radiated electromagnetic (EM) disturbances. It is based on dielectric loading which lessens the susceptibility of ICs independently of frequency by confining the reactive fields inside the dielectric load. This has no side effects on the IC performance. To highlight the importance of the proposed technique, immunity testing was performed numerically both in near and far fields. A loaded IC (a microcontroller) was compared to an unloaded one through far-field measurements inside a transverse EM cell to indirectly assess the suitability of the proposed approach. Results show that loading the IC with non-ferromagnetic dielectric material not only effectively decreases its susceptibility to electric field, but also to magnetic field. Moreover, a significant difference of ∼48% less failure rate was achieved for the loaded compared to the unloaded IC demonstrating the usefulness of this technique as a potential solution for radiated immunity improvement.

International audiencePredicting the immunity of electronic boards to radiated electromagnetic interference requires the computation of the coupling efficiency of an electromagnetic field to PCB traces. In the case of complex PCBs, full-wave electromagnetic solvers are convenient, yet at the expense of simulation time. Therefore, this paper introduces the extension of a modified Taylor-based analytical model to the case of traces terminated at one end by a non-characteristic impedance. This model makes it possible to determine the far-field-to-trace coupling using only a sum of closed-form equations. When applied to a shorted, meandered PCB trace, it was found to be as precise as 2.2 dB average absolute error with respect to GTEM measurements, which demonstrates its relevance for immunity prediction. Moreover, the full-wave simulation of this case study was validated using the extended model and found to be as precise as 1.4 dB average absolute error