Abstract: An external power supply converts AC power to DC Power for a device. The external power supply and the device comprise circuits that provide early AC input failure detection so that the device can take measures such as to safe keep data as long as the external power supply continues to provide DC power to the device.

Abstract: The current invention relates to the reuse of elements in an device to provide multiple functions of function indication, remote control command reception and touch sensor. The device comprises an indicator element providing a first function of indicating to a user the operating state of the said device, a receiver element providing a second function of reception of remote control commands from a remote control device, means for combining the indicator element and the receiver element to provide a third function of touch sensor. The indicator element provides the first function during a subsequent second period of time and the receiver element providing the second function during the second of the time, the first and the second period of time being continuously alternated.

Abstract: The invention relates to switch mode power supply modules and items of equipment powered by these modules. The power supply module comprises circuits for cyclically interrupting the switching operation, during a so-called switching operation interruption phase, if the load current of the module is less than a current threshold value and sustaining the switching operation, during a so-called switching operation phase, if the load current is greater than the load current threshold value and circuits for ending the switching operation interruption phase if the power supply voltage of the item of equipment is greater than a voltage threshold value. The item of equipment powered by the module comprises a capacitive element able to store energy from the module during the switching operation phase and to release the energy stored between the output terminals of the power supply module when it receives an activation signal.

Abstract: The invention concerns a method and device for controlling the switching operation in a switch mode power supply module. The switch mode power supply module is intended to supply power to an item of equipment. The method comprises the steps of measuring, in the switch mode power supply module, the load current and comparing the measured load current with a predefined load current threshold value, and, cyclically interrupting the switching operation if the measured load current inside the device is less than the predefined load current threshold value.

Abstract: The invention relates to switch mode power supply modules and items of equipment powered by these modules. The power supply module comprises means for cyclically interrupting the switching operation, during a so-called switching operation interruption phase, if the load current of the module is less than a current threshold value and sustaining the switching operation, during a so-called switching operation phase, if the load current is greater than the load current threshold value and means for ending the switching operation interruption phase if the power supply voltage of the item of equipment is greater than a voltage threshold value. The item of equipment powered by the module comprises a capacitive element able to store energy from the module during the switching operation phase and means for releasing the energy stored between the output terminals of the power supply module when it receives an activation signal.

Abstract: An external power supply converts AC power to DC Power for a device. The external power supply and the device comprise circuits that provide early AC input failure detection so that the device can take measures such as to safe keep data as long as the external power supply continues to provide DC power to the device.

Abstract: The current invention relates to the reuse of elements in an device to provide multiple functions of function indication, remote control command reception and touch sensor. The device comprises an indicator element providing a first function of indicating to a user the operating state of the said device, a receiver element providing a second function of reception of remote control commands from a remote control device, means for combining the indicator element and the receiver element to provide a third function of touch sensor. The indicator element provides the first function during a subsequent second period of time and the receiver element providing the second function during the second of the time, the first and the second period of time being continuously alternated.

Abstract: A circuit for controlling illumination means in a display includes illumination means arranged in a series-connection that are supplied with an essentially constant current. For individually controlling the illumination means, switches are provided for bypassing individual illumination means, maintaining the essentially constant current in the series-connection. The switches are floating with respect to a ground potential. A coupling means is thus provided for proper control of the switches. In a development of the invention a floating local power supply is provided with each illumination means and switch for operating the switch. The local power supply is, in one embodiment, powered by the control signal that is used for controlling the bypass switch. In another embodiment provision is made for supplying power to the floating local power supply. A driving method according to the embodiments of the circuit is also described.

Abstract: The present invention concerns a device for generating a rectangular sustain voltage between the line scanning electrodes and the line common electrodes of luminous cells in a plasma panel. The device includes a first sustain amplifier connected to the line scanning electrode of the cells to produce the transitions of the first sustain voltage signal, and a second sustain amplifier connected to the line common electrode of the cells to produce the transitions of the second sustain voltage signal. It also includes an insulated voltage supply circuit which is connected directly to the line scanning electrodes and to the line common electrodes of the cells in order to hold the end-of-transition voltage on said line scanning electrodes and said line common electrodes.

Abstract: The invention relates to a backlight device with light emissive diodes not requiring the supply of a large current. According to the invention, each light emissive diode of the backlight device is combined with a voltage converter capable of storing energy during part of the operating cycle and then discharging this energy into the light emissive diode during another part of the cycle.

Abstract: To generate a rising or falling edge simultaneously on the electrodes Ys and Ysa of a plasma display cell, the invention provides for the use of the power recovery circuit of the control device in order to apply, to one of the electrodes Yas and Y, the rising edge applied to the other of the electrodes by a dedicated circuit.

Abstract: The present invention concerns a device for generating a rectangular sustain voltage between the line scanning electrodes and the line common electrodes of luminous cells in a plasma panel. The device includes a first sustain amplifier connected to the line scanning electrode of the cells to produce the transitions of the first sustain voltage signal, and a second sustain amplifier connected to the line common electrode of the cells to produce the transitions of the second sustain voltage signal. It also includes an insulated voltage supply circuit which is connected directly to the line scanning electrodes and to the line common electrodes of the cells in order to hold the end-of-transition voltage on said line scanning electrodes and said line common electrodes.

Abstract: The invention relates to a driver for a plasma display panel. According to the invention, in order to reduce the current loops during the sustain of the display cells, a novel driver architecture is proposed. The switches of the sustain circuit, together with the switches, are disposed next to one another on the circuit board. In addition, the connectors accessing the display electrodes are placed, at the periphery of the board, on the same edge.

Abstract: The switched mode power supply comprises an inductor, a switching transistor coupled in series with the inductor, and a rectifier circuit. The rectifier circuit comprises a switch coupled with the inductor for a rectification of an output voltage and a control circuit operating in a monostable mode. The switch is operated in particular in a synchronous mode with the same switching frequency as the switching transistor. The rectifier circuit can be used advantageously with a switched mode power supply having a push-pull half-bridge configuration and operating as a resonant converter or a quasi-resonant converter with soft switching for an application within a plasma television set.

Abstract: Provided is a device for supplying an array of electrodes of a plasma display panel, the device including, for each electrode, a driver having a series of switches and a series of diodes, the common points of which are connected to the electrode. The upper terminal of the series of diodes is connected directly to the output of a sustain generator and the lower terminal is connected to the sustain generator via a power switch. One of the terminals of the series of switches is connected to the output of a negative voltage generator. In periods during which the negative voltage generator applies a negative voltage to the electrodes, the power switch is open in order to avoid a short-circuit via the diode of the sustain generator.

Abstract: In a display device images are reproduced by controlling the amount of light provided by a light source by means of light modulators for individual pixels. Subsequent images are synchronised to each other by synchronisation signals regularly occurring at intervals corresponding to first time periods. The backlight is controlled to emit light during fractions of second time periods or whole second time periods which are equal to or shorter than first time periods. Several of the second time periods may be nested and evenly distributed within the first time period. The signals for driving the backlight are preferably generated in synchronism with the horizontal pixel clock. Each of the fractions of second time periods or whole second time periods during which light is emitted is divided into a number of elementary steps, wherein each elementary step corresponds to a number of pixel clock periods.

Abstract: The present invention relates to a DC voltage converter with soft switching of the type with half-bridge arrangement at the primary side and of quasi-resonant half-wave type at the secondary side. This converter comprises a single transformer and can generate a plurality of regulated voltages at output. It furthermore comprises a resonant circuit for creating a half-wave resonant current in the secondary winding and charging a first load capacitor so as to produce a first DC voltage. It furthermore comprises an inductive circuit connected between said secondary winding and a second load capacitor able to generate a current so as to charge the second load capacitor during a part of the half-wave of the resonant current flowing in the secondary winding and thus produce a second DC voltage.

Abstract: The invention relates to a device comprising a metallic support plate, the front face of which supports a plasma discharge panel which is equipped with a network of pairs of adjacent electrodes and the rear face of which is equipped with a power supply. According to the invention, the connection ends of the electrodes of one electrode pair are located on opposite edges of the panel and the power circuit of each pair of adjacent electrodes forms a current loop that does not surround the metallic plate. In this way, electric losses are restricted in said plate and the cells of the panel operate identically along the entire length of the electrodes.

Abstract: An image display device is disclosed including a metallic support plate carrying, on its front face, a plasma discharge display with an array of adjacent pairs of electrodes and, on its back face, a power supply. The power supply circuit of each pair of adjacent electrodes forms a current loop starting from the power supply and passing through the electrode then the electrode of the pair, the connection end of the electrode being linked to the power supply by means of a transverse electrical conductor placed on the front side of said metallic plate. According to the invention, the transverse conductor linked to the electrode forms a non-zero angle with said pair of electrodes. The differences in inductance between the various current loops of the display are thus reduced such that the differences in luminance between the various discharge regions of the plasma display are reduced.

Abstract: The present invention relates to a DC voltage converter with soft switching of the type with half-bridge arrangement at the primary side and of quasi-resonant half-wave type at the secondary side. This converter comprises a single transformer and can generate a plurality of regulated voltages at output. It furthermore comprises a resonant circuit for creating a half-wave resonant current in the secondary winding and charging a first load capacitor so as to produce a first DC voltage. It furthermore comprises an inductive circuit connected between said secondary winding and a second load capacitor able to generate a current so as to charge the second load capacitor during a part of the half-wave of the resonant current flowing in the secondary winding and thus produce a second DC voltage.