ES2405541T3

ES2405541T3 - LED control

Info

Publication number: ES2405541T3
Application number: ES08712596T
Authority: ES
Inventors: Laurentius Gerhardus Maria Sneujink
Original assignee: ESQUISSE
Current assignee: ESQUISSE
Priority date: 2007-02-23
Filing date: 2008-02-25
Publication date: 2013-05-31
Anticipated expiration: 2028-02-25
Also published as: EP2127484B1; WO2008103032A1; NL1033446C2; EP2127484A1

Abstract

Método para controlar al menos un componente (15) emisor de luz, tal como un diodo emisor de luz (LED), que tiene una tensión (Vf(max)) y una corriente (If(max)) operativas máximas a las cuales el componente puede activarse con seguriadad, cuyo método comprende: - aplicar una tensión de suministro al componente (15) que sea al menos igual a una tensión mínima para activar el componente (15), - conectar y desconectar selectivamente el componente (15);- al menos uno de - medir la corriente a través del componente (15) y generar una señal de corriente, y - medir la tensión a través del componente (15) y generar una señal de tensión; y - generar una señal de control sobre la base de al menos una de las señal de corriente y la señal de tensión con el fin de conectar y desconectar el componente (15) de acuerdo con ella, caracterizado por: - aplicar al componente (15) una tensión mayor que la tensión operativa máxima Vf(max); - generar una indicación de potencia usando tanto la señal de corriente como la señal de tensión; y - proporcionar la señal de control con la forma de la indicación de potencia, y - conmutar el componente sobre la base de la indicación de potencia.Method for controlling at least one light emitting component (15), such as a light emitting diode (LED), which has a maximum operating voltage (Vf (max)) and a current (If (max)) at which the component can be activated safely, whose method comprises: - applying a supply voltage to the component (15) that is at least equal to a minimum voltage to activate the component (15), - selectively connecting and disconnecting the component (15); - at least one of - measuring the current through the component (15) and generating a current signal, and - measuring the voltage through the component (15) and generating a voltage signal; and - generating a control signal on the basis of at least one of the current signal and the voltage signal in order to connect and disconnect the component (15) accordingly, characterized by: - applying to the component (15 ) a voltage greater than the maximum operating voltage Vf (max); - generate a power indication using both the current signal and the voltage signal; and - provide the control signal in the form of the power indication, and - switch the component on the basis of the power indication.

Description

Control de LEDs LED control

La presente invenci6n se refiere a un metodo para controlar un componente emisor de luz, tal como un LED, que tiene, por un lado, una tensi6n activa minima y, por otro lado, una tensi6n y corriente operativas maximas. The present invention relates to a method of controlling a light emitting component, such as an LED, which has, on the one hand, a minimum active voltage and, on the other hand, a maximum operating voltage and current.

5 Una senal de control para unos medios de conmutaci6n se genera usualmente, o se deduce sobre la base de una senal de corriente medida. La tensi6n de suministro o control de un diodo, o de una serie de diodos, no se tiene aqui en cuenta en su totalidad. Esta tensi6n debe estar preferiblemente en todo momento dentro de un rango determinado con precisi6n de tensiones minimas con el fin de permitir la activaci6n del componente, y una tensi6n maxima, tambien conocida como la tensi6n directa, y la corriente correspondiente, que no puede superarse para no 5 A control signal for switching means is usually generated, or deduced on the basis of a measured current signal. The supply or control voltage of a diode, or a series of diodes, is not fully taken into account here. This voltage should preferably be at all times within a certain range with the precision of minimum voltages in order to allow the activation of the component, and a maximum voltage, also known as the direct voltage, and the corresponding current, which cannot be exceeded for no

10 provocar danos al componente. Los componentes tienen tambien ademas una combinaci6n de una corriente maxima y una tensi6n maxima a las cuales aun puede tolerarse la generaci6n de calor. 10 cause damage to the component. The components also also have a combination of a maximum current and a maximum voltage at which heat generation can still be tolerated.

Las publicaciones US-2004/066.143 y "Consideraciones de Diseno Electrico para LEDs SuperFlux" (2002-09, Lumileds Lighting, San Jose, CA, USA, XP002453166) describen posibilidades de LEDs y estas se reconocen en el presente documento como tecnica anterior. Publications US-2004 / 066.143 and "Electrical Design Considerations for SuperFlux LEDs" (2002-09, Lumileds Lighting, San Jose, CA, USA, XP002453166) describe possibilities of LEDs and these are recognized herein as prior art.

15 Particularmente en aplicaciones en las que una serie de componentes emisores de luz estan conectados en serie entre ellos, las tensiones minima y maxima que se han de aplicar sobre ellos deben aumentarse un numero de veces igual al numero de componentes de la conexi6n en serie. Ademas, los componentes emisores de luz muestran a menudo una fluctuaci6n, dependiendo de la temperatura, etc., en la tensi6n directa minima y maxima que permite que esta entre o permanezca en operaci6n sin danos como resultado de la generaci6n de calor. La 15 Particularly in applications where a series of light emitting components are connected in series with each other, the minimum and maximum voltages to be applied on them must be increased a number of times equal to the number of components of the serial connection. In addition, the light emitting components often show a fluctuation, depending on the temperature, etc., in the minimum and maximum direct voltage that allows it to enter or remain in operation without damage as a result of heat generation. The

20 tensi6n sobre un componente puede, por ejemplo, llegar a ser mas alta para que sea capaz de hacerlo operativo cuando aumenta la temperatura de este diodo, particularmente durante su operaci6n. 20 voltage on a component may, for example, become higher so that it is capable of making it operational when the temperature of this diode increases, particularly during its operation.

Particularmente cuando una serie de componentes emisores de luz estan conectados en serie, la tensi6n total sobre tal conexi6n en serie de componentes puede mostrar grandes fluctuaciones, parcialmente dependiendo de la temperatura. Para compensar esta situaci6n, es usual en la tecnica emplear amplificadores para ajustar la tensi6n 25 de suministro o control de (la serie de) componentes emisores de luz a sus condiciones operativas, y normalmente se hace uso para este fin de amplificadores lineales, amplificadores reforzadores, amplificadores en oposici6n o combinaciones de los mismos. Una tensi6n de 150 V puede ser particularmente necesaria en, por ejemplo, una conexi6n en serie de 35 LEDs. Las fluctuaciones pueden variar hasta tanto como 20 V en la tensi6n que se ha de aplicar sobre la conexi6n en serie. Esta tensi6n debe modificarse segun las condiciones, en particular la temperatura Particularly when a series of light emitting components are connected in series, the total voltage on such a series connection of components can show large fluctuations, partially depending on the temperature. To compensate for this situation, it is usual in the art to use amplifiers to adjust the supply or control voltage of (the series of) light emitting components to their operating conditions, and use is usually made for this purpose of linear amplifiers, booster amplifiers. , opposing amplifiers or combinations thereof. A voltage of 150 V may be particularly necessary in, for example, a serial connection of 35 LEDs. The fluctuations can vary as much as 20 V in the voltage to be applied on the serial connection. This voltage must be modified according to the conditions, in particular the temperature

30 de los componentes emisores de luz, y otras propiedades de los mismos. 30 of the light emitting components, and other properties thereof.

La presente invenci6n tiene por objeto obviar o al menos aliviar los problemas antes mencionados de la tecnica conocida. Para es fin de proporciona un metodo y un control que se distinguen de los controles conocidos por las combinaciones de propiedades y medidas definidas en las reivindicaciones independientes. The present invention is intended to obviate or at least alleviate the aforementioned problems of the known technique. For the purpose of providing a method and control that are distinguished from the controls known by the combinations of properties and measures defined in the independent claims.

Los medios de conmutaci6n se controlan asi sobre la base de una potencia que es momentanea y esta sujeta a The switching means are thus controlled on the basis of a power that is momentary and is subject to

35 unas condiciones, sin tener que aplicar amplificaciones complejas en combinaci6n con el suministro de potencia. Esto impide que la tensi6n tenga que controlarse por separado, en particular la tensi6n directa, si tiene lugar una conmutaci6n sobre la base de la corriente. Esto proporciona un alto grado de libertad en el diseno, y aqui se puede aplicar una tensi6n sobre la (serie de) componentes emisores de luz que puede ser notablemente mas alta que la tensi6n directa usual, sin tener en cuenta variaciones de tensi6n inducidas por diferencia de temperatura. La 35 conditions, without having to apply complex amplifications in combination with the power supply. This prevents the voltage from having to be controlled separately, in particular the direct voltage, if a switching takes place on the basis of the current. This provides a high degree of freedom in the design, and here a tension can be applied on the (series of) light emitting components that can be noticeably higher than the usual direct voltage, without taking into account differences of voltage induced by difference Of temperature. The

40 elecci6n de la tensi6n de suministro para la (serie de) componentes puede ser asi alto y constante, sin que se requieran amplificadores dificiles y complejos para ajustar las tensi6n que se han de aplicar a los componentes emisores de luz individuales. La invenci6n se basa asi en el entendimiento de que el comportamiento de conmutaci6n de los medios de conmutaci6n entrana la posibilidad de hacer que la tensi6n de suministro sea tan alta que no resulten necesarios ajustes para ninguna fluctuaci6n, dependiente de la temperatura u otras influencias, en The choice of the supply voltage for the (series of) components can thus be high and constant, without requiring difficult and complex amplifiers to adjust the voltage to be applied to the individual light emitting components. The invention is thus based on the understanding that the switching behavior of the switching means will involve the possibility of making the supply voltage so high that no adjustments are necessary for any fluctuation, dependent on temperature or other influences, in

45 los modos operativos minimo y maximo del componente. 45 minimum and maximum operating modes of the component.

Ademas mediante la conmutaci6n sobre la base de la potencia y no s6lo sobre la base de la corriente a traves de los componentes emisores de luz, pueden generarse ajustes de luz predeterminados y mantenerlos estables de una manera sencilla. Furthermore, by switching on the basis of the power and not only on the basis of the current through the light emitting components, predetermined light settings can be generated and kept stable in a simple manner.

Un ejemplo usual de conmutaci6n del conmutador puede basarse, por ejemplo, en modulaci6n de ancho de impulso 50 como senal de control para el conmutador. A usual example of switching the switch can be based, for example, on pulse width modulation 50 as a control signal for the switch.

Se observa que, para fines de control, en tal caso no s6lo se hace uso de la tensi6n en el LED, sino tambien de la corriente a traves del LED. La tensi6n del LED muestra variaciones de temperatura que puede haber sido causadas, It is noted that, for control purposes, in this case not only the voltage in the LED is used, but also the current through the LED. The LED voltage shows temperature variations that may have been caused,

o que son causadas, por cambios en el consumo de potencia RMS del LED, o por un cambio en la temperatura ambiente u otras influencias. or that are caused, by changes in the RMS power consumption of the LED, or by a change in ambient temperature or other influences.

55 Se asume aqui, a modo de ejemplo, que el LED se suministra con su corriente maxima permitida, que se asumen en este ejemplo que igual a 1A, y con una tensi6n permitida maxima Vf del LED de, por ejemplo, 3V. Esto significa un 55 It is assumed here, by way of example, that the LED is supplied with its maximum allowed current, which in this example is assumed to be equal to 1A, and with a maximum permitted voltage Vf of the LED of, for example, 3V. This means a

consumo de potencia de 3W. Debido a que el LED se calienta cada vez mas, su Vf sube. Dado que la corriente se mantiene constante en la mayor parte de excitadores, el consumo de potencia subira si Vf aumenta a 3,5V por la influencia de un aumento de temperatura. Esto da como resultado un consumo de potencia de 3,5W. Lo mismo aplica a la inversa. Si la Vf se mantiene constante aumentara la corriente, y tambien asi el consumo de potencia. 3W power consumption. Because the LED gets hotter and hotter, its Vf goes up. Since the current remains constant in most exciters, the power consumption will rise if Vf increases to 3.5V due to the influence of a temperature increase. This results in a power consumption of 3.5W. The same applies in reverse. If the Vf remains constant, the current will increase, and so will the power consumption.

Por tanto, el LED se arrastra gradualmente hasta un punto en el que el consumo de potencia del LED es igual a la capacidad de enfriamiento que se corresponde con una diferencia de temperatura entre el LED y su entorno. Esto es posible porque la Vf sube mas lentamente que el aumento de la diferencia de temperatura. Therefore, the LED gradually creeps to a point where the power consumption of the LED is equal to the cooling capacity that corresponds to a temperature difference between the LED and its surroundings. This is possible because the Vf rises more slowly than the increase in temperature difference.

Este es el caso en el que This is the case in which

(LED/entorno) (LED / environment)

en el que m es la masa del LED y MTC es el coeficiente de temperatura de masa, y .T es la diferencia de temperatura entre el LED y su entorno. Este es el caso en el que: where m is the mass of the LED and MTC is the mass temperature coefficient, and .T is the temperature difference between the LED and its environment. This is the case in which:

Vf/ (diferencia de temperatura LED/entorno) < 1 Vf / (LED / environment temperature difference) <1

Conmutando ahora el LED de una manera acorde con la invenci6n, por ejemplo, con una senal de control modulada en anchura de impulso dependiendo de Vf*ILED (=Prms), el LED se puede mantener a una temperatura constante. By now switching the LED in a manner according to the invention, for example, with a pulse width modulated control signal depending on Vf * ILED (= Prms), the LED can be kept at a constant temperature.

El LED se conmuta inicialmente con un valor de inicio. Aqui se mantienen los valores Vf=3V e iled = 1A. En estos valores se da el caso de que la potencia es igual a Prms = 3W. El LED se calienta durante la operaci6n y Vf se eleva hasta 3,5V. Irms debe ahora mantener un valor de Irms = 1 A por medio de modulaci6n de anchura de impulso de los medios de conmutador (por ejemplo, FET 17 en la realizaci6n ejemplar que se describe a continuaci6n). A Vf = 3,5V resulta un ciclo de trabajo de 3V/3,5V = 0,857%. Irms llega entonces a 0,857A, dando como resultado un Prms de 3,5V * 0,857A = 3,0W. Aqui se hace uso de una tensi6n de suministro que es la misma que la Vf del LED. En realidad este no es el caso y Vf siempre seguira a Irms. Irms cambia debido a la temperatura o a la tensi6n de suministro. The LED is initially switched with a start value. Here the values Vf = 3V and iled = 1A are maintained. In these values it is the case that the power is equal to Prms = 3W. The LED is heated during operation and Vf rises to 3.5V. Irms must now maintain a value of Irms = 1 A by means of pulse width modulation of the switching means (for example, FET 17 in the exemplary embodiment described below). At Vf = 3.5V, a duty cycle of 3V / 3.5V = 0.857% results. Irms then reaches 0.857A, resulting in a Prms of 3.5V * 0.857A = 3.0W. Here, use is made of a supply voltage that is the same as the Vf of the LED. Actually this is not the case and Vf will always follow Irms. Irms changes due to temperature or supply voltage.

Por tanto, es posible en la presente invenci6n suministrar al LED una tensi6n de casi 3 veces la Vf maxima permisible. Este es el caso porque las dinamicas del control se hacen tan grandes debido al control sobre la base de potencia en vez de s6lo sobre la base de corriente o tensi6n. Therefore, it is possible in the present invention to supply the LED with a voltage of almost 3 times the maximum permissible Vf. This is the case because the dynamics of the control become so large due to the control on the basis of power instead of only on the basis of current or voltage.

Si cambia la tensi6n de suministro, en particular si sube, aumentara la corriente a traves del LED. If the supply voltage changes, particularly if it rises, the current through the LED will increase.

Se conoce por el documento US2004/066.143 un circuito en el que la Vrms del LED se mantiene constante. Por tanto, no es la Prms la que se mantiene constante (parrafo 0059: Sin embargo, dado que la relaci6n de trabajo de la corriente suministrada se reduce como se describi6 anteriormente, la potencia consumida (Prms) por la unidad 30 de fuente luminosa puede mantenerse aproximadamente constante), sino la Vrms. Controlando s6lo sobre la base de tensiones entre 13 y 18V - segun se describe en el documento US-2004/066.143 - es s6lo posible, por tanto, el control en una porci6n pequena con respecto al rango de control proporcionados por la invenci6n. En consecuencia, el control no tiene lugar aqui sobre la base de la potencia, sino de la tensi6n. La potencia se controla sobre la base de la tensi6n cambiante, mientras que Irms no permanece igual debido a las propiedades de un LED. Por tanto, esto se encuentra, por ejemplo, en el caso de las diferencias de temperatura que puedan ocurrir durante el uso en, por ejemplo, un coche, que segun el documento US 2004/066.143 el control se realiza s6lo muy cerca del Vf de los LEDs, y este valor ciertamente no es superado. Irms se arrastrara asi cuando se suministre un factor de 2 o 3 por encima de los 13V. A circuit is known from US2004 / 066,143 in which the LED Vrms remains constant. Therefore, it is not the Prms that remains constant (paragraph 0059: However, since the working relationship of the supplied current is reduced as described above, the power consumed (Prms) by the light source unit 30 may stay approximately constant), but the Vrms. Controlling only on the basis of voltages between 13 and 18V - as described in document US-2004 / 066.143 - it is only possible, therefore, control in a small portion with respect to the range of control provided by the invention. Consequently, control does not take place here on the basis of power, but of tension. The power is controlled on the basis of the changing voltage, while Irms does not remain the same due to the properties of an LED. Therefore, this is found, for example, in the case of temperature differences that may occur during use in, for example, a car, which according to US 2004 / 066.143 the control is carried out only very close to the Vf of LEDs, and this value is certainly not exceeded. Irms will crawl like this when a factor of 2 or 3 is supplied above 13V.

La base o entrada para este control es, por tanto, la tensi6n y no la potencia. Incluso si el comportamiento de control del control descrito en el documento 2004/066.143 se adapta a las propiedades del LED, el control tiene una configuraci6n y operaci6n completamente diferentes. The basis or input for this control is therefore the voltage and not the power. Even if the control control behavior described in document 2004 / 066.143 is adapted to the properties of the LED, the control has a completely different configuration and operation.

Todos los otros excitadores de LED funcionan con una bobina y controlan la tensi6n de los LEDs sujetos a la corriente a traves de una resistencia medidora. En el documento US-2006/261752 se dispone una resistencia Rs y en el documento US-2003/076051 se aplica una R3, mientras que un control dependiente de corriente (terminal de control de valor de corriente) se proporciona tambien claramente segun la figura 2 en el documento US2006/0082538, con una resistencia R1 en su figura 3. En el documento W02005/009086 no se controla nada en absoluto, y ademas el circuito comprende una bobina para aumentar la tensi6n (conversor reforzador). All other LED drivers operate with a coil and control the voltage of the LEDs subject to the current through a measuring resistor. In US-2006/261752 a resistance Rs is provided and in US-2003/076051 an R3 is applied, while a current-dependent control (current value control terminal) is also clearly provided according to the figure 2 in US2006 / 0082538, with a resistor R1 in its figure 3. In W02005 / 009086 nothing is controlled at all, and also the circuit comprises a coil to increase the voltage (booster converter).

Existen tambien muchas otras realizaciones preferidas dentro del alcance de la presente invenci6n segun se define en la reivindicaci6n principal, cuyas realizaciones preferidas se indican en las reivindicaciones subordinadas. There are also many other preferred embodiments within the scope of the present invention as defined in the main claim, whose preferred embodiments are indicated in the dependent claims.

Un control segun la invenci6n puede tener asi la caracteristica de que el control comprende un suministro de potencia que se ha de conectar al componente emisor de luz y tiene un valor de tensi6n mayor que una tensi6n A control according to the invention can thus have the characteristic that the control comprises a power supply to be connected to the light emitting component and has a voltage value greater than a voltage

nominal requerida para activar el componente emisor de luz. A este respecto, por tensi6n nominal se entiende como la tensi6n directa necesaria para activar un componente emisor de luz. Seleccionando una tensi6n de suministro que sea mucho mayor que su tensi6n nominal o directa, o una suma aditiva de la misma en el caso de una serie de componentes, y conmutando el conmutador sobre la base de la potencia consumida, puede obtenerse un control preciso de la tensi6n de los componentes emisores de luz individuales, en el caso combinado de las series de los mismos. Por tanto, puede proporcionarse un suministro de potencia mucho mas sencillo con un aumento despreciable de la complejidad del control. El suministro de potencia puede formar parte de otra manera del control. nominal required to activate the light emitting component. In this regard, nominal voltage is understood as the direct voltage required to activate a light emitting component. By selecting a supply voltage that is much greater than its nominal or direct voltage, or an additive sum thereof in the case of a series of components, and switching the switch on the basis of the power consumed, precise control of the tension of the individual light emitting components, in the combined case of the series thereof. Therefore, a much simpler power supply can be provided with a negligible increase in control complexity. The power supply may be part of the control in another way.

En otra realizaci6n preferida, la fuente de potencia se conecta durante el uso a al menos dos componentes emisores de luz y tiene un valor de tensi6n mayor que es tantas veces la tensi6n nominal de cada uno de los componentes emisores de luz como el numero de los mismos. Esto es especifico de la situaci6n en la que se aplica una serie de componentes emisores de luz, cada uno con su propia dependencia de temperatura que, como resultado del control elegido segun la presente invenci6n, no da como resultado una necesidad de un establecimiento y ajuste precisos durante el uso de la tensi6n directa o nominal, pero en el que es suficiente una tensi6n de suministro considerablemente mayor. In another preferred embodiment, the power source is connected during use to at least two light emitting components and has a higher voltage value that is as many times the nominal voltage of each of the light emitting components as the number of the same. This is specific to the situation in which a series of light emitting components are applied, each with its own temperature dependence which, as a result of the control chosen according to the present invention, does not result in a need for establishment and adjustment. precise during the use of direct or nominal voltage, but in which a considerably higher supply voltage is sufficient.

En aun otra realizaci6n preferida de la invenci6n al menos uno del circuito de control, los circuitos medidores, el circuito multiplicador y el de conversi6n, esta conectado, o puede estar conectado a una fuente de potencia con el fin de proporcionar una potencia activa a los componentes emisores luz y al control mismo. El suministro de potencia para los componentes emisores de luz tambien forma asi una fuente de potencia para el control mismo, por lo que la configuraci6n del control segun la presente invenci6n puede permanecer sencilla y en donde puede prescindirse de un suministro de potencia independiente solamente para el control. In yet another preferred embodiment of the invention at least one of the control circuit, the measuring circuits, the multiplier circuit and the conversion circuit, is connected, or can be connected to a power source in order to provide active power to the light emitting components and the control itself. The power supply for the light emitting components thus also forms a power source for the control itself, whereby the configuration of the control according to the present invention can remain simple and where an independent power supply can only be dispensed with only for the control.

En aun otra realizaci6n preferida se puede hacer uso de un circuito de conversi6n con una entrada independiente para el acceso de una senal de sincronizaci6n. Pueden realizarse asi cambios a traves del tiempo en la luz procedente de el unico o de series de al menos un componente emisor de luz sobre la base de la senal de sincronizaci6n. �asta el punto de que la senal de sincronizaci6n puede tenerse en cuenta en la senal de control sobre la base del requerimiento medido por el circuito de medici6n y calculado en el circuito de conversi6n, son posibles patrones de iluminaci6n que varian mucho a lo largo del tiempo con una senal de sincronizaci6n que se ha proporcionar por separado y para la que se proporciona asi una entrada especifica en esta realizaci6n. In yet another preferred embodiment, a conversion circuit with a separate input can be used to access a synchronization signal. Changes can thus be made over time in the light coming from the single or series of at least one light emitting component on the basis of the synchronization signal. To the point that the synchronization signal can be taken into account in the control signal based on the requirement measured by the measurement circuit and calculated in the conversion circuit, lighting patterns that vary greatly throughout the time with a synchronization signal that has been provided separately and for which a specific input is thus provided in this embodiment.

En aun otra realizaci6n preferida es posible que el control sea fabricado en un chip sin componentes externos, tales como una bobina. Se usa normalmente una bobina en los controles de la tecnica anterior, que es y se ha encontrado innecesario segun la presente invenci6n. In yet another preferred embodiment it is possible that the control is manufactured on a chip without external components, such as a coil. A coil is normally used in the prior art controls, which is and has been found unnecessary according to the present invention.

En aun otra realizaci6n preferida es posible que el control segun la invenci6n comprenda un circuito para modulaci6n de anchura de impulso (PWM) en el circuito de conversi6n. El uso de un circuito PWM es conocido por si, aunque no en combinaci6n con el control de un circuito de modulaci6n de anchura de impulso sobre la base de potencias medidas e indicaciones de potencia, segun se propone segun la presente invenci6n. In yet another preferred embodiment it is possible that the control according to the invention comprises a pulse width modulation (PWM) circuit in the conversion circuit. The use of a PWM circuit is known per se, although not in combination with the control of a pulse width modulation circuit based on measured powers and power indications, as proposed according to the present invention.

En aun otra realizaci6n preferida segun la presente invenci6n, unas senales de control que se han de generar por el circuito de conversi6n son impulsadas con una forma de impulso arbitraria. Se puede hacer uso para este fin de diversas variantes de circuitos PWM usuales, que consideran estan dentro del alcance del conocimiento tecnico normal de la persona experta en este campo, y de los cuales no se considera, por tanto, necesaria una descripci6n adicional ahora y mas adelante para los fines de un descubrimiento completo. In yet another preferred embodiment according to the present invention, control signals that are to be generated by the conversion circuit are driven with an arbitrary impulse form. Various variants of usual PWM circuits can be used for this purpose, which they consider are within the scope of the normal technical knowledge of the person skilled in this field, and of which an additional description is now not considered necessary now and later for the purposes of a full discovery.

Pueden aplicarse diversas caracteristicas de elevaci6n y el flanco descendente de las formas de impulso tambien puede ajustarse, segun se desee o se requiera, usando circuitos PWM conocidos por si y usuales, pudiendo tener cada uno de los cuales sus propias ventajas o propiedades en combinaci6n con la presente invenci6n. Various elevation characteristics can be applied and the falling edge of the pulse forms can also be adjusted, as desired or required, using PWM circuits known per se and usual, each of which may have its own advantages or properties in combination with The present invention.

En otra realizaci6n preferida final segun la presente invenci6n el control tiene la caracteristica de que se proporcionan unos medios determinadores con el fin de determinar la relaci6n entre la tensi6n activa sobre el al menos un diodo emisor de luz y la tensi6n de una resistencia en derivaci6n, y en donde este relaci6n puede introducirse dentro del circuito de conversi6n. De esta manera, puede realizarse una optimizaci6n del funcionamiento del control con el fin de ejecutar el mejor control posible del componente emisor de luz o de una serie con componente emisores de luz diversos. In another final preferred embodiment according to the present invention the control has the characteristic that determining means are provided in order to determine the relationship between the active voltage on the at least one light emitting diode and the voltage of a shunt resistor, and where this relationship can be introduced into the conversion circuit. In this way, an optimization of the control operation can be performed in order to execute the best possible control of the light emitting component or of a series with various light emitting components.

Se observa que, debido particularmente al uso de una tensi6n de suministro en el componente o componentes emisores de luz que sea mayor que la tensi6n directa o nominal necesaria para activar el componente o componentes emisores de luz, estos pueden controlarse a distancias mayores con perdidas inferiores, particularmente cuando el control esta situado en el lugar del componente o componentes emisores de luz y la fuente de potencia para aplicar una tensi6n operativa sobre el componente o componentes esta situada a cierta distancia. A una tensi6n de suministro mayor, tiene lugar perdidas relativamente menores en cualquier caso a lo largo de la longitud de los conductores hasta el componente o componentes emisores de luz. It is noted that, due in particular to the use of a supply voltage in the light emitting component or components that is greater than the direct or nominal voltage necessary to activate the light emitting component or components, these can be controlled at greater distances with lower losses. , particularly when the control is located in the place of the light emitting component or components and the power source for applying an operating voltage on the component or components is located at a certain distance. At a higher supply voltage, relatively minor losses occur in any case along the length of the conductors to the light emitting component or components.

La invenci6n se explicara adicionalmente a continuaci6n sobre la base de un solo ejemplo de una posible realizaci6n segun se muestra en los dibujos anexos, en los que los mismos o similares componentes estan designados con los mismos numeros de referencia, y en los que: The invention will be further explained below on the basis of a single example of a possible embodiment as shown in the accompanying drawings, in which the same or similar components are designated with the same reference numbers, and in which:

La figura 1 muestra una vista esquematica de una parte de una posible realizaci6n de un control segun la presente invenci6n� y Figure 1 shows a schematic view of a part of a possible realization of a control according to the present invention and

La figura 2 muestra una vista esquematica de una parte adicional de un control en una realizaci6n posible segun la presente invenci6n. Figure 2 shows a schematic view of an additional part of a control in a possible embodiment according to the present invention.

La figura 1 muestra una parte 1 de control en una posible realizaci6n de la presente invenci6n. La parte 1 del control de la figura 1 comprende dos entradas 2, 3 para respectivamente la tensi6n de LED y la corriente de LED. Las entradas 2, 3 estan conectadas a unos amplificadores respectivos 5, 6, cuyas salidas conducen hasta un multiplicador 4. La salida del multiplicador 4 conduce hasta un circuito sumador 8, en donde la senal de salida procedente del multiplicador 4 puede combinarse con una senal de realimentaci6n relativa a un desplazamiento del ajuste de frecuencia del conmutador que actua sobre los componentes emisores de luz, segun se describira adicionalmente a continuaci6n con referencia a la figura 2. Figure 1 shows a control part 1 in a possible embodiment of the present invention. Part 1 of the control of Figure 1 comprises two inputs 2, 3 for respectively the LED voltage and the LED current. The inputs 2, 3 are connected to respective amplifiers 5, 6, whose outputs lead to a multiplier 4. The output of the multiplier 4 leads to an adder circuit 8, where the output signal from the multiplier 4 can be combined with a signal of feedback relating to a shift in the frequency setting of the switch acting on the light emitting components, as will be described further below with reference to Figure 2.

La salida del circuito sumador esta conectada a una de las entradas de un circuito diferencial 10, en donde la otra entrada del circuito 10 esta conectada a la salida del circuito diferencial 10 con el fin de formar un bucle de realimentaci6n. La salida del circuito diferencial 10 forma parte de un circuito de conversi6n, junto con los componentes mostrados en la figura 2, como parte del control segun la presente invenci6n. Se genera una senal en la salida del circuito diferencial 10, cuya senal puede llevarse hasta un control 11 de PWM a traves de un circuito de procesamiento 12, cuya salida conduce a un oscilador 13 con el fin de hacer adecuada la senal obtenida del circuito diferencial 10 para controlar con ella el oscilador 13 sobre la base de una operaci6n realizada sobre el por el circuito de procesamiento 12. Es posible de otra manera, aunque no necesario, que el oscilador 13 comprenda una entrada adicional 14 para una senal de sincronizaci6n. Tal senal de sincronizaci6n puede usarse para encender o apagar LEDs u otros componentes emisores de luz de una manera deseada segun un ritmo querido o de cualquier otra manera. La figura 2 muestra una conexi6n en serie de tales componentes 15 emisores de luz, de los cuales s6lo dos se muestran explicitamente en la figura 2. The output of the adder circuit is connected to one of the inputs of a differential circuit 10, where the other input of the circuit 10 is connected to the output of the differential circuit 10 in order to form a feedback loop. The output of the differential circuit 10 is part of a conversion circuit, together with the components shown in Figure 2, as part of the control according to the present invention. A signal is generated at the output of the differential circuit 10, whose signal can be carried up to a PWM control 11 through a processing circuit 12, whose output leads to an oscillator 13 in order to make the signal obtained from the differential circuit suitable 10 to control with it the oscillator 13 on the basis of an operation performed on it by the processing circuit 12. It is otherwise possible, but not necessary, that the oscillator 13 comprises an additional input 14 for a synchronization signal. Such a synchronization signal can be used to turn LEDs or other light emitting components on or off in a desired manner according to a desired rhythm or in any other way. Figure 2 shows a serial connection of such light-emitting components 15, of which only two are explicitly shown in Figure 2.

Un conmutador 16 esta dispuesto en linea con las series de LEDs 15, dicho conmutador 16 comprende un transistor 17, en el que la senal de salida del control PWM actua sobre el conmutador 16 con el fin de abrir o mantener cerrada una trayectoria de corriente, segun se requiera. A switch 16 is arranged in line with the series of LEDs 15, said switch 16 comprises a transistor 17, in which the output signal of the PWM control acts on the switch 16 in order to open or keep a current path closed, as required.

Una resistencia en derivaci6n 18 esta dispuesta ademas en la fuente y el drenaje del transistor 17. Esta resistencia en derivaci6n 18 puede usar para proporcionar las diversas mediciones que pueden presentarte en la entrada 2 o, adicional o alternativamente, puede introducirse de otra manera en la parte 1 del control de la figura 1 en la entrada A shunt resistor 18 is also arranged at the source and drain of the transistor 17. This shunt resistor 18 can be used to provide the various measurements that can be presented to you at input 2 or, additionally or alternatively, can be otherwise introduced into the part 1 of the control of figure 1 at the entrance

3. La resistencia en derivaci6n puede servir para medir la corriente y, en una configuraci6n posiblemente modificada, tambien puede hacerse uso de la misma para medir la tensi6n. La conexi6n 19 puede conectarse a una fuente de potencia con un valor de tensi6n mayor que la suma de adici6n del valor de tensi6n maximo de cada uno de los LEDs 15. 3. The shunt resistor can be used to measure the current and, in a possibly modified configuration, it can also be used to measure the voltage. The connection 19 can be connected to a power source with a voltage value greater than the sum of addition of the maximum voltage value of each of the LEDs 15.

Resultara evidente que a los expertos se les ocurriran muchas realizaciones alternativas y adicionales despues del examen de lo anterior. Puede asi realizarse una realizaci6n arbitraria con un transistor posible distinto del transistor mostrado en la figura 2. Se dispone adicionalmente una resistencia en derivaci6n, aunque tambien pueden usarse otras construcciones para medir diversas cantidades. En cualquier caso es importante observar que ya no se requiere una bobina en el control. La tensi6n de la conexi6n 19 puede hacerse arbitrariamente alta, pero no arbitrariamente baja. Por ejemplo, no es deseable hacer que la tensi6n de suministro en la conexi6n 19 sea inferior a la suma de las tensiones directas o nominales de cada uno de los LEDs. Unos amplificadores 5 y 6 pueden proporcionar un producto ponderado en la salida del circuito de multiplicaci6n 4. Por ejemplo, es posible enfatizar una corriente o tensi6n mas que otra. Si se desea, puede multiplicarse asi una senal de corriente por un valor distinto de la senal de tensi6n suministrada en la entrada 3. Se puede hacer uso para este fin de los amplificadores 5 y 6. Con una operaci6n suficientemente estable del control, segun la presente invenci6n, puede omitirse una senal de realimentaci6n a traves de un cable 7. Dependiendo de los requisitos, es posible deshacerse de una entrada 14 para introducir cualquier senal de sincronizaci6n. Sin embargo, es posible realizar patrones deseados de conmutaci6n de encendido y apagado de LEDs usando tal senal de sincronizaci6n. Es posible tambien aqui conmutar sobre la base de s6lo corrientes medidas y/o s6lo tensiones medidas. It will be clear that experts will come up with many alternative and additional realizations after examining the above. An arbitrary embodiment can thus be carried out with a possible transistor other than the transistor shown in Fig. 2. A shunt resistor is additionally provided, although other constructions can also be used to measure various quantities. In any case it is important to note that a coil is no longer required in the control. The tension of the connection 19 can be made arbitrarily high, but not arbitrarily low. For example, it is not desirable to make the supply voltage at connection 19 less than the sum of the direct or nominal voltages of each of the LEDs. Amplifiers 5 and 6 can provide a weighted product at the output of multiplication circuit 4. For example, it is possible to emphasize one current or voltage more than another. If desired, a current signal can be multiplied by a value other than the voltage signal supplied at input 3. Use of amplifiers 5 and 6 can be used for this purpose. With a sufficiently stable operation of the control, according to the In the present invention, a feedback signal can be omitted through a cable 7. Depending on the requirements, it is possible to dispose of an input 14 to introduce any synchronization signal. However, it is possible to make desired patterns of switching on and off of LEDs using such a synchronization signal. It is also possible here to switch on the basis of only measured currents and / or only measured voltages.

Claims

1. Method for controlling at least one light emitting component (15), such as a light emitting diode (LED), which has a maximum operating voltage (Vf (max)) and current (If (max)) at which component can be safely activated, whose method comprises:

5 - apply a supply voltage to the component (15) that is at least equal to a minimum voltage to activate the component (15) �

- selectively connect and disconnect component (15) �

- at least one of

* measure the current through the component (15) and generate a current signal, and 10 * measure the voltage through the component (15) and generate a voltage signal� and - generate a control signal based on the minus one of the current signal and the voltage signal

in order to connect and disconnect the component (15) accordingly, characterized by: - applying to the component (15) a voltage greater than the maximum operating voltage Vf (max) � - generating a power indication using both the signal of current as the voltage signal� and

15 - provide the control signal in the form of the power indication, and - switch the component on the basis of the power indication.

2. Method according to claim 1, wherein the connection and disconnection of the component (15) comprises: generating the control signal such that the sum of power intermittently supplied to the component (15) in the connected mode is at most equal to the product of Vf (max) * If (max).

3. Method according to claim 1 or 2, wherein the connection and disconnection of the component (15) comprises: generating the control signal such that a temperature of the component (15) resulting from heat generation is at sumo equal to a threshold value above which there is a danger of damage to component (15).

4. Control of at least one light emitting component (15), such as a light emitting diode (LED), which has a maximum operating voltage (Vf (max)) and current (If (max)) at which it can the component (15) must be safely activated, comprising: - a power supply for the component (15) �

- switching means (16) for activating the light emitting component (15) at a frequency� - at least one of

* a measuring circuit for measuring at least the current through the component (15) and providing a current signal to the control circuit, and

* a measuring circuit for measuring at least the voltage in the component (15) in order to provide a voltage signal to the control circuit,

- a conversion circuit (11, 12, 13) connected to the switching means (16) to provide the switching means with a switching frequency control signal corresponding to at least one of the current signal and signal of tension,

characterized because

the power source supplies a voltage greater than the maximum operating voltage Vf (max) to the component (15), wherein the conversion circuit comprises a generator (4) to generate a power indication using both the current signal and the signal voltage in order to provide the power indication to the circuit

40 conversion (11, 12, 13) to provide the control signal to the switching means based on the power indication.

5. Control according to claim 4, wherein a power supplied to component (15) is at most equal to the product of Vf (max) * If (max).

6. Control according to claim 4 or 5, comprising a power source to be connected to the light emitting component (15) and having a voltage value greater than a nominal voltage required to activate

the light emitting component (15). 6

7. 7.: Control segun la reivindicaci6n 6, en el que la fuente de potencia se conecta durante el uso a al menos dos componentes (15) emisores de luz y tiene un valor de tensi6n que es tantas veces la tensi6n nominal de cada uno de los componentes (15) emisores de luz como el numero de ellas. Control according to claim 6, wherein the power source is connected during use to at least two light emitting components (15) and has a voltage value that is so many times the nominal voltage of each of the components (15 ) light emitters as the number of them.

8. 8.: Control segun al menos una de las reivindicaciones anteriores 4-7, en el que al menos uno del circuito de control, Control according to at least one of the preceding claims 4-7, wherein at least one of the control circuit,

5 the measuring circuits, the multiplier (4) and the conversion circuit (11, 12, 13) is connected, or can be connected, to a power source in order to provide active power to the emitting components (15) of light and control.

9. Control according to at least one of the preceding claims 4-8, wherein the conversion circuit comprises an input (14) for the introduction of a synchronization signal.

Control according to at least one of the preceding claims 4-9, which has been manufactured on a chip with external components, such as a coil.

11. Control according to at least one of the preceding claims 4-10, that the conversion circuit comprises a circuit (11) for pulse width modulation (PWM).

12. Control according to at least one of the preceding claims 4-11, wherein the control signals to be generated by the conversion circuit (11, 12, 13) are pulsed with an arbitrary pulse form.

13. Control according to at least one of the preceding claims 4-12, wherein determining means are provided in order to determine the relationship between the active voltage in the at least one light emitting diode and the voltage of a resistor bypass (18), and to introduce this relationship into the conversion circuit (11, 12, 13).