Diode logicDiode logic (or diode-resistor logic) constructs AND and OR logic gates with diodes and resistors. An active device (vacuum tubes in early computers, then transistors in diode–transistor logic) is additionally required to provide logical inversion (NOT) for functional completeness and amplification for voltage level restoration, which diode logic alone can't provide. Since voltage levels weaken with each diode logic stage, multiple stages can't easily be cascaded, limiting diode logic's usefulness.
Parasite (électricité)In electrical networks, a parasitic element is a circuit element (resistance, inductance or capacitance) that is possessed by an electrical component but which it is not desirable for it to have for its intended purpose. For instance, a resistor is designed to possess resistance, but will also possess unwanted parasitic capacitance. Parasitic elements are unavoidable. All conductors possess resistance and inductance and the principles of duality ensure that where there is inductance, there will also be capacitance.
History of the transistorA transistor is a semiconductor device with at least three terminals for connection to an electric circuit. In the common case, the third terminal controls the flow of current between the other two terminals. This can be used for amplification, as in the case of a radio receiver, or for rapid switching, as in the case of digital circuits. The transistor replaced the vacuum-tube triode, also called a (thermionic) valve, which was much larger in size and used significantly more power to operate.
Linear integrated circuitA linear integrated circuit or analog chip is a set of miniature electronic analog circuits formed on a single piece of semiconductor material. The voltage and current at specified points in the circuits of analog chips vary continuously over time. In contrast, digital chips only assign meaning to voltages or currents at discrete levels. In addition to transistors, analog chips often include a larger number of passive elements (capacitors, resistors, and inductors) than digital chips.
Composant semi-conducteurvignette|Aperçu de quelques dispositifs semi-conducteurs encapsulés Un composant semi-conducteur est un composant électronique dont le fonctionnement repose sur les propriétés électroniques d'un matériau semi-conducteur (principalement le silicium, le germanium et l'arséniure de gallium, ainsi que des semi-conducteurs organiques). Sa conductivité se situe entre les conducteurs et les isolants. Les composants semi-conducteurs ont remplacé les tubes à vide dans la plupart des applications.
Transistor radioA transistor radio is a small portable radio receiver that uses transistor-based circuitry. Following the invention of the transistor in 1947—which revolutionized the field of consumer electronics by introducing small but powerful, convenient hand-held devices—the Regency TR-1 was released in 1954 becoming the first commercial transistor radio. The mass-market success of the smaller and cheaper Sony TR-63, released in 1957, led to the transistor radio becoming the most popular electronic communication device of the 1960s and 1970s.
Simulation de phénomènesLa simulation de phénomènes est un outil utilisé dans le domaine de la recherche et du développement. Elle permet d'étudier les réactions d'un système à différentes contraintes pour en déduire les résultats recherchés en se passant d'expérimentation. Les systèmes technologiques (infrastructures, véhicules, réseaux de communication, de transport ou d'énergie) sont soumis à différentes contraintes et actions. Le moyen le plus simple d'étudier leurs réactions serait d'expérimenter, c'est-à-dire d'exercer l'action souhaitée sur l'élément en cause pour observer ou mesurer le résultat.
Integrated circuit layoutIn integrated circuit design, integrated circuit (IC) layout, also known IC mask layout or mask design, is the representation of an integrated circuit in terms of planar geometric shapes which correspond to the patterns of metal, oxide, or semiconductor layers that make up the components of the integrated circuit. Originally the overall process was called tapeout, as historically early ICs used graphical black crepe tape on mylar media for photo imaging (erroneously believed to reference magnetic data—the photo process greatly predated magnetic media).
Logique séquentielleEn théorie des circuits électroniques, la logique séquentielle est un type de logique dont les résultats ne dépendent pas seulement des données actuellement traitées mais aussi des données traitées précédemment. Elle s'oppose à la logique combinatoire, dont les résultats sont fonction et seulement fonction des données actuellement traitées. En d'autres termes, la logique séquentielle utilise la notion de mémoire de stockage (Bascules, registres, etc.) alors que la logique combinatoire n'en a pas.
Depletion and enhancement modesIn field-effect transistors (FETs), depletion mode and enhancement mode are two major transistor types, corresponding to whether the transistor is in an on state or an off state at zero gate–source voltage. Enhancement-mode MOSFETs (metal–oxide–semiconductor FETs) are the common switching elements in most integrated circuits. These devices are off at zero gate–source voltage. NMOS can be turned on by pulling the gate voltage higher than the source voltage, PMOS can be turned on by pulling the gate voltage lower than the source voltage.
Optimisation de codeEn programmation informatique, l'optimisation de code est la pratique consistant à améliorer l'efficacité du code informatique d'un programme ou d'une bibliothèque logicielle. Ces améliorations permettent généralement au programme résultant de s'exécuter plus rapidement, de prendre moins de place en mémoire, de limiter sa consommation de ressources (par exemple les fichiers), ou de consommer moins d'énergie électrique. La règle numéro un de l'optimisation est qu'elle ne doit intervenir qu'une fois que le programme fonctionne et répond aux spécifications fonctionnelles.
Capacitor typesCapacitors are manufactured in many styles, forms, dimensions, and from a large variety of materials. They all contain at least two electrical conductors, called plates, separated by an insulating layer (dielectric). Capacitors are widely used as parts of electrical circuits in many common electrical devices. Capacitors, together with resistors and inductors, belong to the group of passive components in electronic equipment.
