Deutsche Thomson-brandt Gmbh

Thomson Licensing S.a.

L'unite Hermetique

Electronic-werke Deutschland Gmbh

Compagnie Europeenne Pour L'equipment Menager - Cepem

Thomson Electromenager S.a.

Gerard Rilly

Gerard Morizot

Markus Rehm

Daniel Lopez

Thomas Riesle

Harald Roth

Jose I Rodriguez-Duran

Jose I Duran

Hans-Otto Haller

Jacques Plisson

Sylvain Benoit

Francis Bidaud

Jose-I Rodriguez-Duran

Jose I Rodriguez

Jose-Ignacio Rodriguez

Hossein Ahmari

Thomas Schulz

Sean Carthy

Jose-Ignacio Rodriguez-Duran

Yves Francedillaois

Jose Rodriquez-Duran

Erich Weisser

Kim-Ly Kha

Laurent Jeanneteau

Hans-G&uuml;nter Bicheler

Gerhard Morizot

The circuit for stabilizing a high voltage for a picture tube comprises a high-voltage transformer, which has a primary winding and a high-voltage winding, a switch, which is connected in series with the primary winding, and a control loop for high-voltage stabilization. The control voltage of the control loop, with which the switch is driven, is derived from two signals in this case. The first signal is tapped off from a secondary auxiliary winding at the transformer and supplies a static control voltage component, and the second signal is derived directly from the high voltage and supplies a measure of the dynamic loading on the high-voltage generator. The static control voltage component is, in particular, a measure of the value of the high voltage during the vertical line flyback, when the screen is black and the high-voltage transformer is minimally loaded. In this case, the auxiliary winding supplies a voltage which is proportional to the secondary flyback pulse. The second signal is a fast control signal, since it is derived directly from the high voltage.

Circuit for stabilizing a high voltage

A circuit for controlling beam current in a picture tube, which circuit calculates current pictures for the R, G, B beam currents in the picture tube, which largely correspond to real beam currents in the color picture tube. The circuit comprises a comparator/integrator which compares a sum of these current pictures with a beam current information item for the purpose of controlling the R, G, B beam currents and/or the picture sharpness. Gamma correction is carried out in the circuit. The circuit may be of analog or digital construction and may advantageously be integrated in a video processor IC. The present circuit is particularly applicable for television sets or computer monitors.

Circuit for controlling beam current in a picture tube

The switched-mode power supply comprises a secondary winding and four diodes for producing two rectified voltages of the same polarity, one of which can be regulated. A connection of the unregulated voltage has connected to it a variable Zener diode as an error amplifier for transmitting a regulating signal to the primary side. The driver stage provides a pulse-width-modulated square-wave signal for driving the switching transistor which is arranged at a high potential between the operating voltage on the input side and a first connection of the primary winding. The second connection of the primary winding is connected with a Zener diode and provides a stabilized voltage for the driver stage. Arranged between the driver stage and the control electrode of the switching transistor there is a differentiating element which produces positive and negative switching voltages for controlling the switching transistor.

Switched-mode power supply

Transformer comprises a core (K1, K2), a primary winding (W1) and at least one secondary winding (W2), which are arranged as conductors on one or more layers of a flat carrier, and a coil former with a chamber system having chambers (C1, C2), which accommodate the layers with the windings (W1, W2). At least one of the chambers (C1, C2) is closed at least in regions, with the result that long distances for creepage paths are obtained. As a result of this, it is possible to adhere to existing safety regulations for the mains power supply isolation even with very compact dimensions and/or with full utilization of the width available for the conductor tracks. The chamber system can be formed from two or three plastic parts (P1, P2, P3) by mating. The layers with the conductor tracks are routed laterally out of the chamber system in order to make contact with terminals. In an advantageous refinement, webs with metallized slots are arranged on walls of the chamber system, in order to make contact with the conductor tracks (L). The slots are, for example, notched or trough-shaped depressions in which the carrier layers latch into place and are held thereby. The electrical contact afforded by the slots can be additionally supported by a solder-paste application with subsequent soldering. The lateral contacts mean that plated-through holes are avoided in the case of the carrier layers, with the result that the latter can be produced significantly more inexpensively. By virtue of the chamber system, it is possible for the openings in a core, for example an E/E or E/I core, to be utilized significantly better if the transformer has to comply with a sufficient insulation strength, such as in the case of mains power supply isolation, for example.

Transformer

A current supply circuit for an electronic apparatus having standby, normal and economy modes of operation includes a remote control receiver which responds to a remote control signal from a remote control unit to select either mode of operation. A voltage source provides a main voltage which is detected to produce a switching voltage when the main voltage is present. The switching element of a voltage responsive switch is connected to a first input contact in the presence of the switching voltage and to a second input contact in the absence of the switching voltage. The output contact of the voltage responsive switch is connected to an input terminal of the remote control receiver and to a first input terminal of the filter. The output contact is selectively connected to the first and second input contacts in response to the respective presence and absence of the switching voltage to apply a first operating voltage to the first input contact in the presence of the switching voltage and a second operating voltage to the second input contact to place the current supply circuit into the economy mode of operation in the absence of the switching voltage.

Current supply circuit for a consumer electronics apparatus

Switched-mode power supply for a load having a low power supply

In a switch-mode power supply, a transformer is used to transmit power during the forward-sweep time. The transformer is also used to transmit a control or regulating variable during the flyback time.

Switched-mode power supply having a standby mode

A line deflection circuit for a television receiver or a switched-mode power supply operate with a switching transistor that is connected in series with the primary winding of a transformer and is periodically switched on and off by a switching voltage. In such a circuit, appreciable turn-on and turn-off losses, which reduce the overall efficiency of the circuit, are produced at the switching transistor, particularly at higher operating frequencies. Within a control circuit a DC voltage source is connected to the base of the switching transistor via a periodically actuated switch element and a coil having a core and a tap. The two parts of the coil are wound in opposite senses, and the tap is connected via a diode to ground or to the emitter of the switching transistor. The control circuit further includes a charge-reversal path via which, during a demagnetization phase of the coil, the energy stored in the coil in the form of a current is transferred in the form of a negative voltage to a capacitor that is coupled via a second diode to a first part of the coil. The negative voltage is applied during a residual time subsequent to the demagnetization phase as a reverse voltage to the base of the switching transistor.

Control circuit for a switching transistor using a tapped coil with

Alternating current generator for controlling a plasma display screen

Switch mode power supplies produce a brief pulse-like load on the mains and have a high harmonic content. Such a high harmonic load on the mains is undesirable. There are increasingly strict regulations for the level of harmonic loads connected to the mains. The present switch mode power supply includes a series circuit formed by an inductor and a diode connected between a charge capacitor, which is dimensioned to be relatively small, and a pickoff of a primary winding of a transformer of the switch mode power supply. A relatively large energy storage capacitor connected to the primary winding is decoupled from the charge capacitor by a second diode. The series circuit produces an additional charging current, which extends the current which is drawn from the mains during one half cycle of the mains voltage, and reduces the amplitude of the current.

Switch mode power supply circuit with increased power factor for mains

In a switch mode power supply which includes a transformer for DC isolation and a switching transistor, a control transistor which controls the switching transistor is switched on by an appropriate control voltage during the isolating phase until the collector voltage of the switching transistor has fallen to a minimum. The control transistor is preferably switched on during the isolating discharge time and the subsequent oscillation phase of the transformer.

Switch mode power supply circuit

This invention relates to a process and a device for controlling power for a circuit comprising a resonant inverter intended to supply a variable impedance load comprising an inductive component. The invention renders the active power consumed by the load independent of the nature of the load by producing an error signal that is a function of an average value of a current passing through power transistors of the inverter, this error signal being used to control a power modulator controlling the switching of the power transistors. Such a process and device finds particular application to a circuit for controlling power supplied to an inducer and a cooking utensil.

Process and device for controlling power for a circuit for induction

The static frequency converter controlled by a control parameter processing and command generation element includes an active filter at the terminals of a dc/dc converter powering a load, wherein the active filter includes an inductance (L1) in series with a diode (D1) grounded through a condenser (C0) and a switch (K5) controlled by the control parameter processing and command generation element and that the dc/dc converter includes at least one complete bridge, one of the arms of which has two condensers (C1,C2) and the other arm has four switches (K1. . . K4). This converter can be used with all load types that can be controlled by frequency converters, and more particularly to a transformer type inductive load or alternating electric motors, with or without commutators, and particularly to single phase and multiphase asynchronous motors.

Static frequency converter which compensates for fluctuations in a

A switch mode power supply includes a transformer and a switching transistor for turning the primary of the transformer on and off. The secondary of the transformer is connected to a comparator which compares the output voltage to a reference voltage and provides a reverse current to the switching transistor to control the duty cycle of the switching transistor in accordance with the comparison.

Switch mode power supply with output feedback isolation

It is known to provide a large screen area using a picture tube having a plurality of guns. The object is to provide a transition of continuous brightness, so that the partial picture transitions are no longer perceptible. This is achieved in that a picture tube without a shadow mask, but with optical sensors, index regions and optical walls is employed, so that a precise detection of the beam is possible and the partial picture transitions are no longer perceptible. Especially for television receivers and monitors.

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Unterkirnach, Germany

Gerard Rilly