Abstract:
The transistor described consists of a parallel-circuit arrangement of individual transistor cells (41, 42) for power division. In order to isolate automatically the defective cells, fuse-type sections (6, 7) are provided, which in the event of a short circuit isolate the said cells from the remainder. A voltage-controlled switch (9) is provided to improve the isolation provided by the basic fuse-type section (7).
Abstract:
The proposal is for a power supply system, especially for motor vehicles, with a battery (6) and an alternator or three-phase generator (1) with a downstream rectifier (3), the voltage (U1) of which is limited by the cutting in and out of the field current of the generator (1) by means of a voltage regulator (4). The voltage regulator (4) detects the actual value of the voltage at the terminals of the generator (1) and generates a mean field current in the exciting field of the generator (1) in such a way that the voltage of the power supply system remains virtually constant, regardless of the load and rotation speed. Switchgear is provided in order to detect, by means of an auxiliary value at the terminals of the generator (1), any undesirable d.c. voltage drop in the power supply system on the line from the generator (1) to the battery (6) caused by the load current and to compensate it at least approximately. The a.c. voltage (V1) available at the terminals of the generator (1) may be used as the auxiliary value.
Abstract:
The voltage regulator, contrary to the type described in DE-PS 27 38 897, has the additional feature that according to the relative duration of connection of the field current an integral component is formed, and this is fed into the regulating circuit proper. The relative duration of connection of the field current may thus be obtained more or less directly from the switching behaviour of the switching transistor (20) for the field current, or by means of a measurement resistor (33) connected in series to the excitation winding (21).
Abstract:
A circuit having a current regulator with a transistor at the output stage. In the current regulator there is a measurement resistance into which current can be fed from additional current sources (I1 to In), which current is increased or decreased as a function of the output voltage (UA) which occurs. In this way, the power loss in the final stage can be kept at least approximately constant.
Abstract:
On propose un systeme de generateur comprenant un generateur avec autoexcitation (1), un regleur de tension (3), un dispositif de transfert (4) pour la prise en charge du courant qui continue a circuler lors de la deconnexion de l'enroulement d'excitation (2) et un dispositif de reception (9) pour absorber l'energie de reaction lors de la coupure d'une charge (11) du generateur. Le dispositif de transfert (4) joue le role de la diode usuelle (13) de libre passage: il presente un cheminement de courant avec une tension de seuil de passage basse commutable sur une tension de seuil elevee. En fonctionnement normal du generateur (1) le bobinage d'excitation (2) est connecte sur le cheminement avec la tension de seuil de passage basse. Lorsque la charge (11) est separee du generateur, le bobinage d'excitation (2) est connecte au cheminement avec la tension de rupture elevee. Le courant d'excitation decroit rapidement. Ainsi l'energie de reaction qui doit renforcer la protection du reseau de bord (9) est fortement diminuee.
Abstract:
Proposed is a voltage controller (4) for a generator (1), in particular for use in motor vehicles, which, by switching the field current on and off by means of a controlled semiconductor, and acting together with a freewheel loop, generates a medium field current in the field coil (2) of the generator (1) so that the generator voltage remains approximately constant, independent of the load and the rotational speed. The voltage controller (4) includes an integrally acting component to compensate for load-dependent and speed-dependent errors, which is generated by means of a non-linear integrator from the relative time-to-make of the current flowing in the field coil (2) and is fed back to the voltage-controller control loop. Non-linearity of the integrator output is ensured by virtue of the fact that, to form the correction function, the part of the cycle while the current is flowing through the generator field coil (2) and through the controlled semiconductor is processed differently from the part of the cycle while current is flowing through the field coil (2) and through the freewheel diode.
Abstract:
A semiconductor device monolithically integrated on a substrate comprising at least one power diode (3) has a cathode potential (6) higher than the substrate potential (5). Its anode forms the emitter and its cathode forms the basis of a parasitic substrate transistor (4). To reduce the power dissipation caused by this parasitic substrate transistor (4), means (8) are provided to increase the collector series resistance (41) of the parasitic transistor (4).
Abstract:
Proposed is a monolithic-integrated precision reference-voltage source based on the bandgap principle and suitable for use over a wide temperature range. The parabolic temperature/reference-voltage curve produced by the source is made linear using the processing means available in the monolithic integration without the need for additional active components such as transistors and diodes. The precision voltage-reference source includes two resistors (21, 22) represented by the n-doped emitter diffusion zone.
Abstract:
There is disclosed a semiconductor device provided with a metal layer (1, 2) which presents a structured surface in the areas subjected to thermal shock loads. To this effect, there is provided under the metal layer (1) at the top surface of the semiconductor, projecting oxide portions (16) which form in the metal coating layer a predetermined structure. Thus, when because of thermal shock loads, different elongation of the semiconductor material and the metal layer (1) and shearing stresses occur, the top surface opposes any tearing or slitting.