Prediction of soft error response of integrated circuits to electrostatic discharge injection via simulation field; Package interaction for electrostatic discharge soft error prediction; Full wave model for simulating noise ken electrostatic discharge generator

In the first section, a concept for analyzing soft error response in ICs to ESD via coupling through flex cable structures is presented. Its novelty lies in accounting for the transient electromagnetic fields radiated by the ESD generator that couples to the flex cable PCB thereby causing disturbance on the IC under test. This is accomplished in three stages; first by developing a full wave model of the DUT which includes modeling the PCB and flex cable geometry and validating it in frequency domain with regard to the transfer impedance. This followed by combining the ESD generator with the DUT model to simulate the voltage at the IC input in time domain. Finally the time domain results from full wave simulation are combined with an equivalent IC response model in SPICE to predict soft error failures due ESD. In the second section, a more detailed modeling of the IC including the lead frame geometry, bond wires and IBIS/ICEM models are incorporated to investigate coupling of fields from three different injection techniques - H field loop probes, TEM cell and ESD generator. For the first time a complete simulation model which includes the ESD generator, passive elements of the DUT structure (PCB) and a detailed model of the IC has been developed to predict interaction of radiated field from the generator to the IC. The third section shows a CST MWS model was generated to simulate the discharge current and the transient field of an ESD generator. Individual components of the Noise Ken ESD generator (ESS-2000) were modeled, validated and combined. The complete full wave model was verified by comparing the simulated discharge current waveforms and induced loop voltages with the measured results --Abstract, page iii

Validation by Measurements of a IC Modeling Approach for SiP Applications

The growing importance of signal integrity (SI) analysis in integrated circuits (ICs), revealed by modern systemin-package methods, is demanding for new models for the IC sub-systems which are both accurate, efficient and extractable by simple measurement procedures. This paper presents the contribution for the establishment of an integrated IC modeling approach whose performance is assessed by direct comparison with the signals measured in laboratory of two distinct memory IC devices. Based on the identification of the main blocks of a typical IC device, the modeling approach consists of a network of system-level sub-models, some of which with already demonstrated accuracy, which simulated the IC interfacing behavior. Emphasis is given to the procedures that were developed to validate by means of laboratory measurements (and not by comparison with circuit-level simulations) the model performance, which is a novel and important aspect that should be considered in the design of IC models that are useful for SI analysi

Analog-Digital System Modeling for Electromagnetic Susceptibility Prediction

The thesis is focused on the noise susceptibility of communication networks. These analog-mixed signal systems operate in an electrically noisy environment, in presence of multiple equipments connected by means of long wiring. Every module communicates using a transceiver as an interface between the local digital signaling and the data transmission through the network. Hence, the performance of the IC transceiver when affected by disturbances is one of the main factors that guarantees the EM immunity of the whole equipment. The susceptibility to RF and transient disturbances is addressed at component level on a CAN transceiver as a test case, highlighting the IC features critical for noise immunity. A novel procedure is proposed for the IC modeling for mixed-signal immunity simulations of communication networks. The procedure is based on a gray-box approach, modeling IC ports with a physical circuit and the internal links with a behavioural block. The parameters are estimated from time and frequency domain measurements, allowing accurate and efficient reproduction of non-linear device switching behaviours. The effectiveness of the modeling process is verified by applying the proposed technique to a CAN transceiver, involved in a real immunity test on a data communication link. The obtained model is successfully implemented in a commercial solver to predict both the functional signals and the RF noise immunity at component level. The noise immunity at system level is then evaluated on a complete communication network, analyzing the results of several tests on a realistic CAN bus. After developing models for wires and injection probes, a noise immunity test in avionic environment is carried out in a simulation environment, observing good overall accuracy and efficiency

Méthode de prédiction de la compatibilité\ud électromagnétique des systèmes en boîtier

Afin de réaliser des circuits électroniques plus denses et plus performants, les industriels cherchent à intégrer dans un même boîtier plusieurs circuits. Néanmoins, la cohabitation entre un circuit bruyant et un circuit sensible du point de vue CEM pourrait révéler des incompatibilités dont il faut se prémunir. Ce mémoire décrit des méthodologies de prédiction de l impact d un couplage électromagnétique entre deux circuits proches, dans le cadre d un rapprochement entre un microcontrôleur dédié à des applications automobiles et un composant puissance. Le premier chapitre est dédié à l étude de l origine et à la modélisation des émissions parasites et de la susceptibilité des circuits intégrés, et à la prise en compte de ces deux problèmes dans le cas d un rapprochement entre plusieurs circuits. Ensuite, le deuxième chapitre est consacré à la modélisation des émissions rayonnées des circuits en champ proche produites tandis que le troisième s intéresse à la prédiction de la susceptibilité des circuits soumis à des agressions rayonnées localisées. Enfin, dans le dernier chapitre, deux méthodologies de prédiction des risques de défaillances produites par le couplage entre deux circuits proches sont proposées à partir des modèles d émission et de susceptibilité des composants, permettant de tester l effet du placement et des conditions de fonctionnement sur la compatibilité électromagnétique. - In order to achieve more powerful and denser electronic devices, the actual trend in\ud microelectronic industry consists in integrating several circuits inside the same package.\ud However it could involve electromagnetic incompatibility between the different circuits. This\ud report describes some predictive methodologies dedicated to the impact of electromagnetic\ud coupling between two nearby circuits, e.g. in the case of a module composed of a\ud microcontroller and a power device. The first chapter is dedicated to the origin and the\ud modelling of integrated circuit parasitic emission and susceptibility, and EMC problems\ud related to system on package. Then the second chapter deals with integrated circuit near\ud field radiated emission modelling, and the third chapter is dedicated to the susceptibility\ud modelling of components disturbed by localized radiated aggression. Finally two\ud methodologies aiming at predicting failure risks for two nearby components are proposed.\ud They are based on the use of integrated circuit emission and susceptibility electrical\ud models and allow testing the effect of placement and operating conditions on the\ud electromagnetic compatibilit

Constructive Conflict Management and Coping in Homeless Children Adolescents

In this largely exploratory study of the conflict management and coping behavior of homeless adolescents, the authors interviewed 176 families (mother-adolescent dyads) living in New York City welfare hotels. Results indicated that peer conflict was the "worst" problem of the previous month as reported by approximately 50% of these youth. Homeless adolescents demonstrated conflict management and coping patterns that differed in certain respects from adolescent patterns previously described in the literature. The implications of these differences as well as directions for future research are discussed

Structured grid generation for gas turbine combustion systems

Commercial pressures to reduce time-scales encourage innovation in the design and analysis cycle of gas turbine combustion systems. The migration of Computational Fluid Dynamics (CFD) from the purview of the specialist into a routine analysis tool is crucial to achieve these reductions and forms the focus of this research. Two significant challenges were identified: reducing the time-scale for creating and solving a CFD prediction and reducing the level of expertise required to perform a prediction. The commercial pressure for the rapid production of CFD predictions, coupled with the desire to reduce the risk associated with adopting a new technology led, following a review of available techniques, to the identification of structured grids as the current optimum methodology. It was decided that the task of geometry definition would be entirely performed within commercial Computer Aided Design (CAD) systems. A critical success factor for this research was the adoption of solid models for the geometry representation. Solids ensure consistency, and accuracy, whilst eliminating the need for the designer to undertake difficult, and time consuming, geometry repair operations. The versatility of parametric CAD systems were investigated on the complex geometry of a combustion system and found to be useful in reducing the overhead in altering the geometry for a CFD prediction. Accurate and robust transfer between CAD and CFD systems was achieved by the use of direct translators. Restricting the geometry definition to solid models allowed a novel two stage grid generator to be developed. In stage one an initial algebraic grid is created. This reduces user interaction to a minimum, by the employment of a series of logical rules based on the solid model to fill in any missing grid boundary condition data. In stage two the quality of the grid is improved by redistributing nodes using elliptical partial differential equations. A unique approach of improving grid quality by simultaneously smoothing both internal and surface grids was implemented. The smoothing operation was responsible for quality, and therefore reduced the level of grid generation expertise required. The successful validation of this research was demonstrated using several test cases including a CFD prediction of a complete combustion system

Modelação comportamental de dispostivos não-lineares (RF-digital) de entrada/saída

Doutoramento em Engenharia ElectrotécnicaEsta tese investiga a caracterização (e modelação) de dispositivos que realizam o interface entre os domínios digital e analógico, tal como os buffers de saída dos circuitos integrados (CI). Os terminais sem fios da atualidade estão a ser desenvolvidos tendo em vista o conceito de rádio-definido-por-software introduzido por Mitola. Idealmente esta arquitetura tira partido de poderosos processadores e estende a operação dos blocos digitais o mais próximo possível da antena. Neste sentido, não é de estranhar que haja uma crescente preocupação, no seio da comunidade científica, relativamente à caracterização dos blocos que fazem o interface entre os domínios analógico e digital, sendo os conversores digital-analógico e analógico-digital dois bons exemplos destes circuitos. Dentro dos circuitos digitais de alta velocidade, tais como as memórias Flash, um papel semelhante é desempenhado pelos buffers de saída. Estes realizam o interface entre o domínio digital (núcleo lógico) e o domínio analógico (encapsulamento dos CI e parasitas associados às linhas de transmissão), determinando a integridade do sinal transmitido. Por forma a acelerar a análise de integridade do sinal, aquando do projeto de um CI, é fundamental ter modelos que são simultaneamente eficientes (em termos computacionais) e precisos. Tipicamente a extração/validação dos modelos para buffers de saída é feita usando dados obtidos da simulação de um modelo detalhado (ao nível do transístor) ou a partir de resultados experimentais. A última abordagem não envolve problemas de propriedade intelectual; contudo é raramente mencionada na literatura referente à caracterização de buffers de saída. Neste sentido, esta tese de Doutoramento foca-se no desenvolvimento de uma nova configuração de medição para a caracterização e modelação de buffers de saída de alta velocidade, com a natural extensão aos dispositivos amplificadores comutados RF-CMOS. Tendo por base um procedimento experimental bem definido, um modelo estado-da-arte é extraído e validado. A configuração de medição desenvolvida aborda não apenas a integridade dos sinais de saída mas também do barramento de alimentação. Por forma a determinar a sensibilidade das quantias estimadas (tensão e corrente) aos erros presentes nas diversas variáveis associadas ao procedimento experimental, uma análise de incerteza é também apresentada.This thesis investigates the characterization (and modeling) of devices that perform the interface between the digital and analog domains, such as the output buffers of the Integrated Circuits (ICs). Modern wireless transceivers are moving towards the software-defined radio (SDR) concept proposed by Mitola. The ideal architecture makes use of powerful digital signal processors (DSP) and extends the digital blocks’s operation as close as possible to the antenna. In this way, it is not surprising that there is a growing concern regarding the characterization of the blocks that perform the interface between the analog and digital domains, being the analog-to-digital and digital-to-analog converters (ADCs/DACs) two good examples of these circuits. Within the high speed digital circuits, such as Flash memories, a similar role is played by the output buffers. They act as an interface between the digital (logic core) and the analog radio frequency domains (package/printed circuit board), determining the signal integrity of the transmitted data. In order to speed up the signal integrity analysis, at the design stage, it is fundamental to have models that are simultaneously computationally efficient and accurate. Typically, the extraction/validation of models for output buffers is performed by using characterization data obtained from either the simulation of the transistor level model (if available) or from measurements. The latter approach is not sensitive to intellectual property issues but is rarely addressed in literature referred to output buffers’ characterization. Therefore, this thesis addresses the development of a novel measurement setup for the characterization and modeling of high speed output buffers, naturally extendable to switched-mode RF-CMOS amplifiers. Based on a welldefined experimental procedure, a state of the art model is extracted and validated. The developed measurement setup addresses not only the integrity of the output signals (signal integrity) but also of the power supply voltages (power integrity). In order to determine the sensitivity of the estimated quantities (voltage and current) to the errors in the different variables of the experimental procedure, an uncertainty analysis is presented

Power Converters in Power Electronics

In recent years, power converters have played an important role in power electronics technology for different applications, such as renewable energy systems, electric vehicles, pulsed power generation, and biomedical sciences. Power converters, in the realm of power electronics, are becoming essential for generating electrical power energy in various ways. This Special Issue focuses on the development of novel power converter topologies in power electronics. The topics of interest include, but are not limited to: Z-source converters; multilevel power converter topologies; switched-capacitor-based power converters; power converters for battery management systems; power converters in wireless power transfer techniques; the reliability of power conversion systems; and modulation techniques for advanced power converters