Temperature Effect on Lorentz Based Magnetometer

We recently introduced a CMOS-compatible out-of-plane magnetic sensor based on Lorentz force. In the present paper, we analyze the impact of Joule effect on those sensors. At an experimental level, 3-D white light interferometry is used to assert the coupling of thermal, electromagnetic and mechanical effects while, at a simulation level, finite element analysis is performed to correlate device design to experimental data and expand our analysis to optimize new configurations

From KCL to Class D Amplifier

From a circuit point of view, the starting point of the students coming out of the secondary school is roughly limited to describing the flow of electrical charges through a simple loop. Nevertheless, one and a half years later, they can design, simulate, build and test the core of a Class D amplifier while meeting demanding learning objectives. This paper relates the story of a project conducted in the context of an undergraduate electrical engineering program. Circuits and system concepts are introduced from the beginning of the first year in a physics course, and are applied to a project during the second term. A circuit theory course and the Class D amplifier project are run in parallel during the second term of the second year. Effective learning is facilitated by a mixture of lectures covering the necessary concepts and self-directed laboratory experiments allowing active acquisition of problem solving skills. At the end of the project, enthusiastic students can listen to the sound of their MP3 player through the amplifier that results from their teamwork. A survey indicates that the outcomes of the project are in line with the expected results of a problem- and project-based learning environment

Contextualiser et augmenter l'attractivité de l'enseignement de base des circuits électriques via l'étude et la réalisation d'un amplificateur audio de classe D

En Belgique au niveau de la formation des ingénieurs universitaires, la réforme de Bologne a conduit à remplacer l'approche traditionnelle de deux ans de formation générale suivie de trois ans de spécialisation par une approche de type 3+2 (bachelor degree, master) dans laquelle les étudiants choisissent au cours du premier cycle des modules “ techniques ”, tels que l'électricité, la mécanique, la chimie- physique, ..., les préparant à des masters de spécialisation dans ces domaines. Dans ce contexte où des choix se font très tôt dans le curriculum, offrir via des activités de projet une approche qui permet aux étudiants de découvrir des aspects du métier liés à une discipline peut jouer un rôle significatif au niveau de l'attractivité des formations proposées. C'est dans ce contexte que la présente communication décrit une expérience de projet réalisée cette année et montrant comment l'enseignement des circuits électriques peut permettre aux étudiants de comprendre les principes et réaliser un prototype d'un dispositif en prise directe avec la technologie actuelle, à savoir un ampli audio de classe D

Temperature effect on Lorentz based magnetometer

We recently introduced a CMOS-compatible out-of-plane magnetic sensor based on Lorentz force. In the present paper, we analyze the impact of Joule effect on those sensors. At an experimental level, 3-D white light interferometry is used to assert the coupling of thermal, electromagnetic and mechanical effects while, at a simulation level, finite element analysis is performed to correlate device design to experimental data and expand our analysis to optimize new configurations

CMOS Compatible Out-of-Plane & In-Plane Integrated Magnetometer

Three-dimensional MEMS magnetometers with use of residual stresses in thin multilayers are presented. Half-loop cantilevers based on Lorentz-force deflection convert magnetic flux in DeltaV changes thanks to piezoresistive transducers mounted in Wheatstone bridge. Magnetic field in the order of 10 Gauss was measured with a sensitivity of 0.015 mV/Gauss. Ferromagnetic nickel plates also show 20 mum- vertical deflection in magnetic field non-aligned with the residual magnetization

CMOS compatible out-of-plane & in-plane magnetometers

Three-dimensional MEMS magnetometers with use of residual stresses in thin multilayers are presented. Half-loop cantilevers based on Lorentz-force deflection convert magnetic flux in Delta V changes thanks to piezoresistive transducers mounted in Wheatstone bridge. Magnetic field in the order of 10 Gauss was measured with a sensitivity of 0.015 mV/Gauss. Ferromagnetic nickel plates also show 20 mu m- vertical deflection in magnetic field non-aligned with the residual magnetization.Anglai