EP3917287B1 - Control circuit arrangement, motor vehicle headlight or lighting device for a motor vehicle with such a control circuit arrangement and method for controlling a plurality of led devices connected in parallel with such a control circuit arrangement - Google Patents

Description

The present invention relates to a control circuit arrangement according to the preamble of claim 1. The control circuit arrangement comprises in particular an electrical control circuit for controlling a plurality of LED arrangements of a motor vehicle headlight or a motor vehicle light connected in parallel with one another, as well as a plurality of switching elements, with one switching element being assignable to one of the LED arrangements.

The invention further relates to a motor vehicle headlight or a motor vehicle light according to the preamble of claim 13. The motor vehicle headlight or the motor vehicle light comprises a plurality of LED arrangements connected in parallel to one another and a control circuit arrangement comprising a control circuit for controlling the LED arrangements. The Motor vehicle light is designed in particular as a rear light.

Finally, the invention also relates to a method for controlling several LED arrangements connected in parallel by means of a control circuit arrangement comprising a control circuit according to the preamble of claim 14. A supply voltage is applied to two supply voltage inputs of the control circuit, and the LED arrangements are connected to at least two control outputs connected to the control circuit, and an operating current for the LED arrangements is provided by at least one power source of the control circuit.

Electrical control circuits, lighting devices and control methods of the type mentioned at the beginning are, for example, from US 2017/ 295618 A1 and the US 2015/ 061527 A1 known.

Other electrical control circuits, lighting devices and control methods are, for example, from DE 10 2008 021 534 A1 known. Similar state of the art is also available in the DE 100 27 478 A1 , the DE 103 18 780 A1 , the EP 2 744 302 A1 , the WO 2017/ 042 101 A1 and the DE 10 2005 012 625 A1 described.

The known lighting devices each have several LED arrangements, with each LED arrangement comprising several LEDs connected in series. The LED arrangements are controlled by a control circuit. A supply voltage, preferably a battery voltage of a motor vehicle, is applied to the control circuit via two supply voltage inputs. The control circuit has its own separate power source for each LED arrangement, which provides an individual, impressed operating current for the respective LED arrangement. Each of the LED arrangements is connected to the control circuit via two control outputs. A first tax output for each of the LED arrangements is connected to the associated power source and a second control output to ground. The control circuit therefore has at least one separate control output for each of the LED arrangements.

The control circuit arrangements known from the prior art and the lighting devices equipped with them are relatively complex, large and expensive due to the large number of power sources and control outputs. The present invention is based on the object of making control circuit arrangements and lighting devices equipped therewith for motor vehicles simpler, smaller and more cost-effective.

To solve this problem, a control circuit arrangement with the features of claim 1 is proposed. In particular, based on the control circuit arrangement of the type mentioned at the outset, it is proposed that the control circuit is designed to control the LED arrangements in successive clock phases of a repeating control cycle, and the control circuit has a parallel connection of an output capacitor and a further switching element, which are connected in parallel the LED arrangements can be switched, wherein the control unit is designed to also control the further switching element assigned to the output capacitor in order to achieve a faster discharge of the output capacitor, so that when the LED arrangements are operated sequentially within a control cycle, the operating current provided by the power source from one clock phase to a subsequent clock phase within a short time, preferably immediately, from a higher current value for a first LED arrangement to a lower current value for another LED arrangement.

The control circuit is designed to control the LED arrangements of a lighting device in successive clock phases of a repeating control cycle. At least one different LED arrangement is activated in each clock phase. At the end of a tax cycle preferably all LED arrangements have been controlled at least once, whereby the control of an LED arrangement can also include operation of the LED arrangement with an operating current of 0 A. Therefore, by controlling the LED arrangements, the intensity (or brightness) of the light emitted by the LED arrangements can be adjusted and the LED arrangements can be switched on or off. The successive control cycles are preferably carried out at a frequency that does not allow the human eye to distinguish between the LED arrangement being switched on (higher intensity) in a first control cycle and the LED arrangement being switched off or dimmed (lower intensity) in a subsequent control cycle. Rather, the duration of a control cycle is chosen to be so short that the human eye or brain can adjust the different brightness values in successive control cycles averaged to an average. The frequency of the control cycles is therefore preferably above 75 Hz, ie a control cycle lasts less than 13 ms. This means that, for example, with four parallel LED arrangements that can be controlled independently of one another, there remains a duration for a clock phase of approximately 3.3 ms. These are just exemplary values that can be deviated from in practice.

The control of one or more LED arrangements of the lighting device includes, on the one hand, the operating current required for operation or a desired intensity of the emitted light of the currently controlled LED arrangements) via the common power source and, on the other hand, the current flow in the LED arrangements via the switching elements so that the operating current provided by the power source flows through the LED arrangements currently controlled in the respective clock phase. In a clock phase, one LED arrangement or several LED arrangements can be controlled and operated with the operating current provided by the power source. The invention has the advantage that the control circuit only has a common power source for providing an individual operating current for several LED arrangements of the lighting device to be controlled. As a result, the control circuit and the lighting device provided with it can be implemented more simply and cost-effectively. In addition, using only a common power source can result in an increase in the efficiency of the control circuit.

Each of the controlled LED arrangements can emit light that is used to generate a specific light or lighting function of the lighting device or part of it. For example, it would be conceivable that one or more of the LED arrangements are designed to generate a low beam, a high beam, a daytime running light, a position light and/or a flashing light. One or more LED arrangements can also be designed to generate several light or lighting functions, which can be realized by controlling the LED arrangement(s) with different operating currents. In the event that only one of the light or lighting functions (e.g. daytime running lights) is active for a certain period of time, the control method according to the invention can be used with the repetitive control cycles and the sequential clock phase of a control cycle can also be temporarily suspended. In this case, the at least one LED arrangement, which generates the long-term light or lighting function, can then be operated with the corresponding operating current for the desired period of time (e.g. over several control cycles). A resumption of the control cycles with the clock phases is only necessary again when an additional light or lighting function is added.

The control circuit can control several LED arrangements of the lighting device according to the method according to the invention and operate one or more other LED arrangements of the lighting device in a different way, for example according to a method known from the prior art with a separate power source for each of the other operating LEDs -Arrangements. According to an advantageous development of the invention, however, it is proposed that the one common power source of the control circuit is designed to supply all LED arrangements of the lighting device controlled by the control circuit with the individual operating current. In this sense, it is further proposed that a switching element is arranged in each of the LED arrangements of the lighting device which are supplied with the individual operating current by the power source.

According to a preferred embodiment of the invention, it is proposed that the control circuit has two common control outputs for all LED arrangements supplied with the individual operating current by the power source. One of the control outputs is preferably connected to ground and the operating current provided by the common power source is preferably present at the other control output.

It is advantageously provided that the control unit is designed to control the power source and the switching elements in a synchronized manner. As soon as the common current source is set in a clock phase to provide a desired operating current, the switching elements are in the same clock phase controlled in such a way that the operating current provided flows through the LED arrangement(s) to be controlled in this clock phase.

It is proposed that the clock phases of a control cycle be executed sequentially. In this sense, the control unit is designed to sequentially control the power source and the switching elements assigned to the LED arrangements for each of the LED arrangements to which a switching element is assigned. Preferably, the control unit is designed to control the operating current in the respective currently controlled LED arrangement(s) in one of several repeating control cycles by sequentially controlling the power source and the switching elements for each of the LED arrangements to which a switching element is assigned. individually adjustable.

Furthermore, it is proposed that the control unit for controlling the current source specifies a current setpoint that is dependent on the operating current for the currently controlled LED arrangement(s). The current source then either supplies the current setpoint as the operating current or the current source has a control function in order to regulate the supplied operating current as part of a control to the current setpoint. For this purpose, it can be advantageous if the currently supplied operating current is detected, for example by means of a current sensor. This can be arranged in the control circuit at the control output to which the operating current supplied by the common power source is present.

Preferably, each of the LED arrangements comprises at least one LED or a laser diode. The LED arrangements can also include any other semiconductor light sources. The LEDs can be, for example, white LEDs that emit white light. It would also be conceivable that the LEDs are red, yellow and/or blue LEDs, which together form RGB LEDs. LEDs of one color are preferably arranged in an LED arrangement. In the event that at least one of the LED arrangements comprises several LEDs or laser diodes, these are preferably connected in series. The individual LED arrangements can vary in number and/or type (e.g. RGB LEDs, conventional white LEDs or high-performance LEDs) differ from LEDs or laser diodes. This can result in different operating currents that are required for the LED arrangements to operate properly. It is also conceivable that different types of LEDs or laser diodes are arranged within an LED arrangement. Furthermore, it cannot be ruled out that several LEDs or laser diodes are connected in parallel to one another within an LED arrangement.

Preferably, the switching elements assigned to the LED arrangements are each connected in series to the at least one LED or laser diode of the corresponding LED arrangement. In this way, the current flow through the LED arrangements can be controlled, in particular interrupted or switched through, by the switching elements.

A parallel connection of an output capacitor and a further switching element is connected in parallel to the LED arrangements of the lighting device, with the control unit being designed to also control the further switching element assigned to the output capacitor. The entire parallel connection is part of the control circuit. The output capacitor can be used to - if necessary - provide a faster reduction in the operating current between one clock phase and the next. For this purpose, the output capacitor can be discharged to the current value of the subsequent (smaller) operating current amplitude if necessary. To discharge the output capacitor, the additional switching element is closed so that the capacitor can (partially) discharge via ground.

Particularly preferably, the control unit is designed to control (or close) the further switching element assigned to the output capacitor following the control of a switching element, which is one of the LED arrangements is assigned. The further control element is therefore preferably activated at the end of each clock phase of a control cycle.

The object on which the present invention is based is also achieved by a lighting device in the form of a motor vehicle headlight or a motor vehicle light with the features of claim 13. In particular, it is proposed that the lighting device, in addition to the LED arrangements connected in parallel to one another, has a control circuit arrangement according to the invention with the control circuit for controlling the LED arrangements. The lighting device is preferably designed as a motor vehicle headlight or as any motor vehicle light, in particular as a rear light, which realizes various lighting functions (e.g. taillight, brake light, rear fog light, reversing light, flashing light). At least one of the LED arrangements can be assigned to each of these lighting functions. All of these lighting functions can be implemented in the lighting device according to the invention by a common power source.

• die LED-Anordnungen von der Steuerschaltung in aufeinander folgenden Takt-Phasen eines sich wiederholenden Steuerzyklus angesteuert werden, und
• eine Parallelschaltung eines Ausgangskondensators und eines weiteren Schaltelements Teil der Steuerschaltungsanordnung ist und parallel zu den LEDAnordnungen geschaltet wird, wobei das Schaltelement auch von der Steuereinheit gesteuert wird, um ein schnelleres Entladen des Ausgangskondensators zu erreichen, sodass bei einem sequenziellen Betrieb der LED-Anordnungen innerhalb eines Steuerzyklus der von der Stromquelle bereitgestellte Betriebsstrom von einer Takt-Phase zu einer darauffolgenden Takt-Phase innerhalb kurzer Zeit, vorzugsweise sofort, von einem höheren Stromwert für eine erste LED-Anordnung auf einen niedrigeren Stromwert für eine andere LED-Anordnung fallen kann.

Furthermore, the object on which the present invention is based is achieved by a control method with the features of claim 14. In particular, based on the tax procedure of the type mentioned at the beginning, it is proposed that

• the LED arrangements are controlled by the control circuit in successive clock phases of a repeating control cycle, and
• a parallel connection of an output capacitor and a further switching element is part of the control circuit arrangement and is connected in parallel to the LED arrangements, the switching element also being controlled by the control unit in order to achieve faster discharging of the output capacitor, so that in sequential operation of the LED arrangements within a control cycle, the operating current provided by the power source from one clock phase to a subsequent clock phase within a short time, preferably immediately, from a higher current value for a first LED arrangement to a lower current value for another LED Order can fall.

Figur 1

eine erfindungsgemäße Steuerschaltungsanordnung in einer bevorzugten Ausführungsform;

Figur 2

eine Steuerung von LED-Anordnungen gemäß einem erfindungsgemäßen Verfahren in einer bevorzugten Ausführungsform;

Figur 3

eine Steuerung von LED-Anordnungen gemäß einem erfindungsgemäßen Verfahren in einer alternativen Ausführungsform;

Figur 4

eine erfindungsgemäße Beleuchtungseinrichtung in einer bevorzugten Ausführungsform.

Further features and advantages of the present invention are explained in more detail below with reference to the figures. Individuals in the figures can also do this The features shown and described below may in themselves be essential to the invention, even if this is not expressly mentioned. In addition, the individual features shown in the figures and described below can be combined with one another in any way, even if this is not shown or expressly mentioned. Show it:

Figure 1

a control circuit arrangement according to the invention in a preferred embodiment;

Figure 2

a control of LED arrangements according to a method according to the invention in a preferred embodiment;

Figure 3

a control of LED arrangements according to a method according to the invention in an alternative embodiment;

Figure 4

a lighting device according to the invention in a preferred embodiment.

In Figure 4 is a lighting device according to the invention for motor vehicles in the form of a headlight, in particular for cars or trucks, designated in its entirety by the reference number 101. However, corresponding headlights can also be used in trains, trams, boats, ships or airplanes. Of course, the lighting device 101 can also be designed as a motor vehicle light, in particular as a rear light. The following statements relating to headlights therefore apply equally to motor vehicle lights.

The headlight 101 includes a housing 102, which is preferably made of plastic. In a light exit direction 103, the headlight housing 102 has a light exit opening which is closed by a transparent cover plate 104. The cover plate 104 is made of colorless plastic or glass. The pane 104 can be designed as a so-called clear pane without optically effective profiles. Alternatively, the disk 104 can be at least partially be provided with optically effective profiles (e.g. cylindrical lenses or prisms) which cause the light passing through to scatter, preferably in a horizontal direction. The headlight 101 is intended for installation on a mounting side of a motor vehicle. Two of the headlights 101 shown, which are arranged on different mounting sides of the motor vehicle, form a motor vehicle lighting device according to the invention. The headlights 101 installed on different mounting sides are preferably designed to be mirror-symmetrical to one another with regard to their general geometric external appearance.

In the example shown, two light modules 105, 106 are arranged inside the headlight housing 102. The light modules 105, 106 are arranged to be fixed or movable relative to the housing 102. A dynamic cornering light function can be implemented by moving the light modules 105, 106 relative to the housing 102 in the horizontal direction. When the light modules 105, 106 move about a horizontal axis, i.e. in the vertical direction, headlight range control can be implemented. Of course, more or fewer than the two light modules 105, 106 shown can also be provided in the headlight housing 102. One or more of the light modules 105, 106 of the headlight 101 can have a lamp according to the invention as a light source, which will be explained in detail below.

The light module 105 can be designed to generate different light distributions, for example a low beam, a high beam and a partial high beam or parts thereof (e.g. a low beam basic light, a low beam spot, a high beam basic light, a high beam spot, etc.). It is conceivable that the light distributions of the light modules 105, 106 complement the resulting light distribution of the headlight 101. It is also conceivable that the light distributions of the light modules of headlights 101 arranged on different mounting sides of the motor vehicle complement the resulting light distribution of the lighting arrangement comprising both headlights 101.

On the outside of the headlight housing 102, a control device 107 is arranged in a control device housing 108. Of course, the control device 107 can also be arranged at any other location on the headlight 101. In particular, a separate control device can be provided for each of the light modules 105, 106, whereby the control devices can be an integral part of the light modules 105, 106. Of course, the control unit 107 can also be arranged away from the headlight 101, for example in the engine compartment of the motor vehicle. The control device 107 is used to control and/or regulate the light modules 105, 106 or partial components of the light modules 105, 106, such as, for example, lamps of the light modules 105, 106. The control of the light modules 105, 106 or the partial components by the control device 107 takes place via connecting lines 110, which are in Figure 4 are only symbolically represented by a dashed line. The light modules 105, 106 can also be supplied with electrical energy via the lines 110. The lines 110 are led from the interior of the headlight 101 through an opening in the headlight housing 102 into the control unit housing 108 and are connected there to the circuit of the control unit 107. If control devices are provided as an integral part of the light modules 105, 106, the lines 110 and the opening in the headlight housing 102 can be omitted. The control device 107 includes a plug element 109 for connecting a connecting cable to a higher-level control unit (eg in the form of a so-called body controller unit) and/or an energy source (eg in the form of the vehicle battery).

The light modules 105, 106 of the lighting device 101 can have several LED arrangements arranged parallel to one another, as shown for example in Figure 1 are shown and are designated by the reference numbers 2.1, 2.2, 2.3, 2.i (together reference number 2). The light modules are used to generate one or more light functions, such as low beam, high beam, fog light, etc. Of course, the LED arrangements 2 can also be part of one or more light modules arranged inside the housing 102, which are used to generate one or more Lighting functions such as daytime running lights, position lights, flashing lights, etc. are used. Finally, it would also be conceivable that part of the LED arrangements 2.1, 2.2, 2.3, 2.i is part of a light module 105, 106 and another part of the LED arrangements 2.1, 2.2, 2.3, 2.i is part of a lighting module of the lighting device 101, which can also be arranged in the housing 102 and can be used to generate any lighting function. The LED arrangements 2 are preferably controlled by a common control circuit arrangement comprising an electrical control circuit 4.

Each of the LED arrangements 2 includes one or more semiconductor light sources 6, for example LEDs or laser diodes. If several semiconductor light sources 6 are provided in an LED arrangement 2, they are preferably connected in series. The same number of semiconductor light sources 6 can be provided in the LED arrangements 2. However, it is also conceivable that the LED arrangements 2 have a different number of semiconductor light sources 6. The semiconductor light sources 6 can be of the same type (e.g. LEDs, OLEDs, conventional laser diodes, VCSELs, normal white LEDs, high-power LEDs, RGB LEDs, etc.) or different types. In addition, at least some of the semiconductor light sources 6 in an LED arrangement 2 can also be connected in parallel. Furthermore, further electrical components can also be arranged in the LED arrangements 2, preferably connected in series with the semiconductor light sources 6.

The electrical control circuit 4 has two supply voltage inputs 8a, 8b, at which a supply voltage, for example a battery voltage U _Batt of a vehicle battery or a voltage provided by a higher-level control unit (for example in the form of a so-called body controller unit), is present. The control circuit 4 is preferably arranged in the control device 107 of the lighting device 101. Furthermore, the control circuit 4 comprises at least two control outputs, in the present case exactly two control outputs 10a, 10b, for connecting the LED arrangements 2. An operating voltage for the LED arrangements 2 is preferably present at one of the control outputs 10a, and the other control output 10b is on ground.

Furthermore, the control circuit 4 has a common electrically controllable current source 12 for providing an operating current I_1, I_2, I_3, I_i (together I) for the LED arrangements 2.1, 2.2, 2.3, 2.i via the control outputs 10a, 10b. In particular, the current source 12 can be caused by control to provide an individual operating current I_1, I_2, I_3, I_i for at least some of the LED arrangements 2.1, 2.2, 2.3, 2.i controlled by the control circuit 4. The current source 12 can be a known bridge circuit (e.g. in the form of an H-bridge) and/or a known DC-DC converter (e.g. in the form of a single-ended primary inductor converter; SEPIC) and/or an have a known up-converter (so-called boost or step-up converter) and/or a known down-converter (so-called buck or step-down converter).

In the branches of the LED arrangements 2, for which the current source 12 provides the operating current I_1, I_2, I_3, I_i, a switching element S_1, S_2, S_3, S_i (together S) is arranged or the corresponding LED arrangements 2.1, 2.2, 2.3, 2.i assigned. The switching elements S_1, S_2, S_3, S_i are - in addition to the control circuit 4 - part of the control circuit arrangement according to the invention.

By actuating or controlling the switching elements S_1, S_2, S_3, S_i, the operating current I_1, I_2, I_3, I_i flowing in the respective branch or through the respective LED arrangement 2.1, 2.2, 2.3, 2.i can be switched. In particular, the current flow can be interrupted or switched through by the switching elements S. The switching elements S are preferably designed as electrically controllable semiconductor switches, for example as transistors. Advantageously, S MOSFETs with a particularly low resistance R _DSon between drain and source in the switched-on state are used as switching elements. The MOSFETs used also preferably have a minimal parasitic capacitance. Alternatively, the switching elements S can also be designed as bipolar transistors or as other types of controllable switches.

Finally, the control circuit 4 includes a control unit 14 for controlling the power source 12 via a control signal CTRL_Current and for controlling the switching elements S via one or more control signals CTRL_Switches. The control unit 14 can include a processing unit with a processor, in particular a microcontroller. A computer program (so-called control program) can run on this, which is programmed to carry out the control method according to the invention, and which carries out the execution of the control method caused by the control circuit 4 when it runs on the processor or microcontroller. The power source 12 and the control unit 14 can be integrated in a common ASIC. The control unit 14 can have a DAC (Digital Analog Converter) that sends a current setpoint to the H-bridge of the power source 12. Due to the time-critical application, this is preferably done via DMA functionality (Direct Memory Access) of the control unit 14.

The current source 12 is controlled in such a way that it has a suitable operating current I_1; I_2; I_3 or I_i for at least one selected LED arrangement 2.1; 2.2; 2.3; 2.i provides. The switching elements S are controlled in such a way that the operating current I_1; provided by the power source 12; I_2; I_3 or I_i through the at least one selected LED arrangement 2.1; 2.2; 2.3; 2.i flows. The switching elements S are preferably controlled synchronously with the control of the current source 12, possibly with a small time delay to the control of the current source 12, in order to give the current source 12 a short time to provide the appropriate operating current I.

The control of the current source 12 preferably includes specifying a current setpoint. The current source 12 can then provide an operating current I corresponding to the predetermined setpoint in a controlled manner. Alternatively, the current source 12 can also regulate the operating current I to the specified setpoint as part of a current control. For this purpose, it may be necessary to measure the current operating current I (actual current value), for example using a current sensor 22. This can be arranged in the control circuit 4 at the control output 10a (so-called high-side path), to which the operating voltage is applied.

For example, in order to operate the LED arrangement 2.1 in the first branch with the appropriate operating current I_1, the current source 12 is controlled in such a way that it provides the appropriate operating current I_1. The switching elements S_2, S_3 and S_i, which are assigned to the LED arrangements 2.2, 2.3 and 2.i, are controlled in such a way that they are open and interrupt the current flow through the corresponding branches. The switching element S_1, which is assigned to the LED arrangement 2.1, is controlled in such a way that it closes and the current flows through it corresponding branch possible. The operating current I_1 thus flows through the first branch and the LED arrangement 2.1. In a corresponding manner, the remaining LED arrangements 2.2, 2.3, 2.i can be operated with the appropriate operating current I_2, I_3, I_i by suitable control of the current source 12 and the switch S.

The various LED arrangements 2 can be designed to generate one or more light functions or lighting functions of the lighting device 101 or part of a light or lighting function. By operating one or more of the LED arrangements 2, the resulting light or lighting function generated by the lighting device 101 can be switched on or off. Possible light or lighting functions of the headlight 101, which can be generated by one or more of the LED arrangements 2, are, for example, low beam, high beam, daytime running light, position light or flashing light. In the case of a taillight, the light or lighting functions can include, for example, taillight, brake light, rear fog light, reversing light or indicator light.

The control of the current source 12 and the switch S preferably takes place in several consecutive clock phases T_1, T_2. T_3, T_i (together T) of a control cycle, as exemplified in Figure 2 is shown. The clock phases T of a control cycle are preferably the same length; but they can also be of different lengths. During the clock phases T of a control cycle, all LED arrangements 2 are preferably controlled sequentially. However, it would also be conceivable that only some of the LED arrangements 2 of the lighting device 101 are controlled in a control cycle.

As part of the control method according to the invention of the LED arrangements 2, several repeating control cycles are preferably run through one after the other. The successive control cycles are preferably carried out at a frequency that does not allow the human eye to distinguish between the LED arrangement 2 being switched on (or higher intensity) in a first control cycle and the LED arrangement 2 being switched off or dimmed (or lower intensity) in one following control cycle. The duration of one The control cycle is preferably chosen to be so short that the human eye or brain averages the different brightness values in successive control cycles to form an average value. The frequency of the control cycles is therefore preferably above 75 Hz, ie a control cycle lasts less than 13 ms. Thus, for example, with four parallel LED arrangements 2 to be controlled independently of one another, there remains a duration for a clock phase T of approximately 3.3 ms or less. In the example shown, a control cycle lasts 5 ms, so that with four LED arrangements 2 to be controlled, a clock phase T lasts 1.25 ms. The individual LED arrangements 2 are thus controlled with a frequency of 200 Hz. This is also the frequency with which the control cycles are repeated.

In the Figure 2 The light or lighting functions shown, which are generated by the various LED arrangements 2, include low beam (LB), high beam (HB), daytime running light (DRL), position light (POS), and Flashing light (Turn Indicator; TI). Deviating from the example of Figure 2 It would also be conceivable for several LED arrangements 2 to be controlled or operated simultaneously in a clock phase T, provided that they are operated with an operating current I of the same size. In this way, for example, an LED arrangement 2 for generating a low beam that illuminates a short area (below a light-dark limit) in the resulting light distribution can be used at the same time as another LED arrangement 2 for illuminating a long-distance area (above the light-dark limit) of the resulting light distribution be operated in order to generate a high beam that complies with the regulations as a whole. To do this, it is sufficient to adapt the tax procedure or the tax program accordingly. Furthermore, it differs from the example of Figure 2 It is conceivable that the LED arrangements 2 are operated in an order other than that shown.

The amplitudes of the operating current I_1, I_2, I_3, I_i in the different clock phases T preferably differ from one another, depending on the number and type of semiconductor light sources 6 in the LED arrangements 2 and depending on the light or lighting function to be generated. During the sequential operation of the LED arrangements 2 within a control cycle, it can happen that the one from the Current source 12 provided operating current I must fall from a clock phase T to the subsequent clock phase T within a short time, preferably immediately, from a higher current value for a first LED arrangement 2 to a lower current value for another LED arrangement 2.

The following table shows an example of a control of the current source 12 and the switching elements S in a control cycle. Of course, the control can also be designed differently. Light function Clock phase Bar duration Current amplitude Current value L.B T_1 1.25ms I_1 800mA HB T_2 1.25ms I_2 850mA DRL/POS T_3 1.25ms I_3 680mA T.I T_i 1.25ms I_i 750mA

An output capacitor 16 is connected between the control output 10a, to which the operating voltage for the LED arrangements 2 is present, and ground. Furthermore, a further electrically controllable switching element 18 is connected in parallel between the control output 10a and ground. The output capacitor 16 and the further switching element 18 are part of the electrical control circuit 4. A resistor 20 can be arranged in the branch of the further switching element 18. If the further switching element 18 is closed, a current I_CLR can flow via this branch. This can be used to discharge the output capacitor 18 more quickly. Furthermore, current peaks that are harmful to the operation of the LED arrangements 2 and which can be caused by the recharging process can be reduced.

The control method or the control program can also be adapted in such a way that the output capacitor 18 is discharged afterwards or on At the end of a clock phase T_i only takes place up to the final value of a smaller current amplitude of the subsequent clock phase T_i+1. Likewise, discharging the output capacitor 18 can be completely dispensed with if the current amplitude of the subsequent clock phase T_i+1 is greater than the current amplitude of the current clock phase T_i.

The further switching element 18 is preferably activated after or at the end of a clock phase T, ie closed. This is exemplified in Figure 3 shown. The activation duration of the further switching element 18 is preferably shorter than the previous clock phase T. In the example shown, the activation of the further switching element 18 takes 0.5 ms, so that there is a period duration of 7 ms and a frequency for controlling the individual LED arrangements 2 of about 143 Hz. Of course, other control durations or durations of the clock phases T are also conceivable.

The present invention makes it possible to generate independent variable current amplitudes I in successive clock phases T and to operate the corresponding LED arrangements 2 variably and independently of one another by controlling the switching elements S. This allows the number of power sources 12 in the control circuit 4 to be limited to just one. The control circuit 4 can therefore be used to supply several independent branches with LED arrangements 2 with variable operating current and operating voltage. The invention provides a solution that requires fewer components and can therefore be implemented more cost-effectively. In addition, the control circuit 4 can lead to an increase in efficiency, since there are fewer losses in the circuit 4 due to the fact that there is only one common power source 12.

It is also conceivable to adapt the control method or the control program in such a way that the clock phases T are suspended as long as only one light function (e.g. daytime running lights) is active, i.e. as long as only one or more LED arrangements 2 are used to generate this light function be operated with the appropriate operating current I. In this case, a control cycle would only include the one clock phase T for generating the one light function.

It is also conceivable to adapt the control method or the control program in such a way that the brightness of the light emitted by the currently controlled LED arrangement 2 is dimmed within one or more clock phases T, for example by means of pulse width modulation (PWM) of the operating current I he follows.

As a result, the operating current I provided by the current source 12 can be reduced again in selected clock phases T.

A temperature sensor for detecting an operating temperature of the semiconductor light sources 6 can be provided in the lighting device 101, preferably in the vicinity of the semiconductor light sources 6 of the LED arrangements 2. Preferably, at least one temperature sensor is assigned to each of the LED arrangements 2. If the detected temperature exceeds a predeterminable limit value, the operating current I can be reduced within one or more clock phases T to reduce the power consumption. This can be done either by appropriately controlling the power source 12 or by the PWM described.

• den elektrischen Eigenschaften der Halbleiterlichtquellen 6 der LED-Anordnung 2,
• der Anzahl der Halbleiterlichtquellen 6 in der LED-Anordnung 2,
• der Schaltung (seriell und/oder parallel) der Halbleiterlichtquellen 6 der LED-Anordnung 2, und/oder
• den Helligkeitsanforderungen an das von der LED-Anordnung 2 ausgesandte Licht, und/oder
• von der Takt-Phase T.

The maximum current amplitude in a specific clock phase T for the currently controlled LED arrangement 2 should be selected depending on one or more of the following criteria:

• the electrical properties of the semiconductor light sources 6 of the LED arrangement 2,
• the number of semiconductor light sources 6 in the LED arrangement 2,
• the circuit (serial and/or parallel) of the semiconductor light sources 6 of the LED arrangement 2, and/or
• the brightness requirements for the light emitted by the LED arrangement 2, and/or
• from the clock phase T.

The following table shows examples of some possible light profiles which can be implemented correspondingly to control the power source 12 and the switching elements S. Of course, other combinations are also possible. Light profile/cycle T_1 T_2 T_3 T_i Day DRL Day and flashing DRL T.I Day and headlight flasher DRL HB Day and flashing and flashing lights DRL T.I HB Night L.B POS Night & Flashing L.B POS T.I Night and flashing lights L.B POS HB Night and flashing and flashing lights L.B POS T.I HB

Claims (14)

1. Control circuit arrangement comprising an electrical control circuit (4) for controlling a plurality of LED arrangements (2.1, 2.2, 2.3, 2.i) of a motor vehicle headlight (101) or of a motor vehicle lamp, the LED arrangements (2.1, 2.2, 2.3, 2.i) being connected in parallel with one another and designed to generate one or more headlight functions of the headlight (101) or lighting functions of the lamp or part of a headlight or lighting function,

   the control circuit (4) comprising two supply voltage inputs (8a, 8b) for applying a supply voltage (U_Batt), at least two control outputs (10a, 10b) for connecting the LED arrangements (2.1, 2.2, 2.3, 2.i) and a common controllable current source (12), which is designed to provide an individual operating current (I_1; I_2; I_3; I_i) for the LED arrangements (2.1, 2.2, 2.3, 2.i) controlled by the control circuit (4) via the control outputs (10a, 10b),

   wherein the control circuit arrangement comprises a plurality of switching elements (S_1, S_2, S_3, S_i), wherein in each case one switching element (S_1; S_2; S_3; S_i) can be assigned to one of the LED arrangements (2.1, 2.2, 2.3, 2.i) for which the current source (12) provides the operating current (I_1; I_2; I_3; I_i), and the switching elements (S_1, S_2, S_3, S_i) are designed to supply the operating current (I_1; I_2; I_3; I_i) in the LED arrangement (2.1; 2.2; 2.3; 2.i) assigned to the respective switching element (S_1, S_2, S_3, S_i), and

   wherein the control circuit (4) further comprises a control unit (14) which is designed to control the current source (12) in such a way that it provides the operating current (I_1; I_2; I_3; I_i) for the controlled LED arrangements (2.1; 2.2; 2.3; 2.i), and to control the switching elements (S_1, S_2, S_3, S_i) in such a way that the operating current (I_1; I_2; I_3; I_i) provided by the current source (12) flows through the at least one LED arrangement (2.1; 2.2; 2.3; 2.i) which is currently being controlled,

   characterised in that

   the control circuit (4) is designed to control the LED arrangements (2.1, 2.2, 2.3, 2.i) in successive clock phases (T_1, T_2, T_3, T_i) of a repetitive control cycle, and

   the control circuit (4) has a parallel circuit of an output capacitor (16) and a further switching element (18), which can be switched in parallel with the LED arrangements (2.1, 2.2, 2.3, 2.i), wherein the control unit (14) is designed to also control the further switching element (18) assigned to the output capacitor (16) in order to achieve a faster discharge of the output capacitor (16), so that during sequential operation of the LED arrangements (2.1; 2. 2; 2.3; 2.i) within a control cycle, the operating current (I_1; I_2; I_3; I_i) provided by the current source (12) changes from one clock phase (T_i) to a subsequent clock phase (T_i+1) within a short time, preferably immediately, from a higher current value for a first LED arrangement (2.1) of the LED arrangements (2.1, 2.2, 2.3, 2.i) to a lower current value for another LED arrangement (2.2; 2.3; 2.i) of the LED arrangements (2.1, 2.2, 2.3, 2.i).
2. Control circuit arrangement according to claim 1, characterised in that the current source (12) is designed to supply all LED arrangements (2.1, 2.2, 2.3, 2.i) controlled by the control circuit (4) with the individual operating current (I_1; I_2; I_3; I_i).
3. Control circuit arrangement according to claim 1 or 2, characterised in that a switching element (S_1; S_2; S_3; S_i) can be arranged in each of the LED arrangements (2.1, 2.2, 2.3, 2.i) supplied with the individual operating current (I_1; I_2; I_3; I_i) by the current source (12).
4. Control circuit arrangement according to one of the preceding claims, characterised in that the at least two control outputs (10a, 10b) of the control circuit (4) comprise two common control outputs (10a, 10b) for all LED arrangements (2.1, 2.2, 2.3, 2.i) supplied with the individual operating current (I_1; I_2; I_3; I_i) by the current source (12).
5. Control circuit arrangement according to one of the preceding claims, characterised in that the control unit (14) is designed to control the current source (12) and the switching elements (S_1, S_2, S_3, S_i) in a synchronised manner.
6. Control circuit arrangement according to one of the preceding claims, characterised in that the control unit (14) is designed to control the current source (12) and the switching elements (S_1, S_2, S_3, S_i) assigned to the LED arrangements (2.1, 2. 2, 2.3, 2.i), for each of the LED arrangements (2.1, 2.2, 2.3, 2.i), to which a switching element (S_1; S_2; S_3; S_i) is assigned, sequentially.
7. Control circuit arrangement according to claim 6, characterised in that the control unit (14) is designed to individually set the operating current (I_1; I_2; I_3; I_i) in the respective LED arrangement (2.1; 2.2; 2.3; 2.i), in one of several repetitive control cycles by sequentially controlling the current source (12) and the switching elements (S_1, S_2, S_3, S_i) for each of the LED arrangements (2.1, 2.2, 2.3, 2.i), to which a switching element (S_1; S_2; S_3; S_i) is assigned.
8. Control circuit arrangement according to one of the preceding claims, characterised in that the control unit (14) for controlling the current source (12) specifies a current setpoint value (CTRL_Current) for the latter, which is dependent on the operating current (I_1; I_2; I_3; I_i) for the currently controlled LED arrangement (2.1; 2.2; 2.3; 2.i).
9. Control circuit arrangement according to one of the preceding claims, characterised in that each of the LED arrangements (2.1, 2.2, 2.3, 2.i) comprises at least one semiconductor light source (6), in particular an LED or a laser diode.
10. Control circuit arrangement according to one of the preceding claims, characterised in that each of the LED arrangements (2.1, 2.2, 2.3, 2.i) comprises a plurality of semiconductor light sources (6), in particular LEDs or laser diodes, which are connected in series.
11. Control circuit arrangement according to one of the preceding claims, characterised in that the switching elements (S_1, S_2, S_3, S_i) assigned to the LED arrangements (2.1, 2.2, 2.3, 2.i) are each connected in series with the at least one semiconductor light source (6) of one of the LED arrangements (2.1, 2.2, 2.3, 2.i).
12. Control circuit arrangement according to one of the preceding claims, characterised in that the control unit (14) is designed to control the further switching element (18) assigned to the output capacitor (16) following the control of a switching element (S_1; S_2; S_3; S_i) which is assigned to one of the LED arrangements (2.1, 2.2, 2.3, 2.i).
13. Motor vehicle headlight (101) or motor vehicle lamp, comprising a plurality of LED arrangements (2.1, 2.2, 2.3, 2.i) connected in parallel with one another, wherein the LED arrangements (2.1, 2.2, 2.3, 2.i) are designed to generate one or more headlight functions of the headlight (101) or lighting functions of the lamp or part of a headlight or lighting function, and a control circuit arrangement having a control circuit (4) for controlling the LED arrangements (2.1, 2.2, 2.3, 2.i) according to one of the preceding claims.
14. Method for controlling a plurality of LED arrangements (2.1, 2.2, 2.3, 2.i) of a motor vehicle headlight (101) or a motor vehicle lamp, wherein the LED arrangements (2.1, 2.2, 2.3, 2.i) are connected in parallel with one another and designed to generate one or more headlight functions of the headlight (101) or lighting functions of the lamp or part of a headlight or lighting function, by means of a control circuit arrangement comprising a control circuit (4), wherein a supply voltage (U_Batt) is applied to two supply voltage inputs (8a, 8b) of the control circuit (4), the LED arrangements (2.1, 2.2, 2.3, 2.i) are connected to at least two control outputs (10a, 10b) of the control circuit (4), and an operating current (I_1, I_2, I_3, I_i) for the LED arrangements (2.1, 2.2, 2.3, 2.i) is provided by a common controllable current source (12) of the control circuit (4), wherein

    - an individual operating current (I_1; I_2; I_3; I_i) is provided by the current source (12) for the LED arrangements (2.1, 2.2, 2.3, 2.i) controlled by the control circuit (4),

    - the current source (12) is controlled by a control unit (14) of the control circuit (4) in order to provide the individual operating current (I_1; I_2; I_3; I_i) for the controlled LED arrangements (2.1; 2.2; 2.3; 2.i), and

    - in each case one switching element (S_1; S_2; S_3; S_i) of the control circuit arrangement is assigned to one of the LED arrangements (2.1, 2.2, 2.3, 2.i) for which the current source (12) provides the operating current (I_1; I_2; I_3; I_i), and the switching elements (S_1, S_2, S_3, S_i) are controlled by the control unit (14) so that the individual operating current (I_1; I_2; I_3; I_i) provided by the current source (12) flows through the at least one currently controlled LED arrangement (2.1; 2.2; 2.3; 2.i),

    characterised in that

    the LED arrangements (2.1, 2.2, 2.3, 2.i) are driven by the control circuit (4) in successive clock phases (T_1, T_2, T_3, T_i) of a repetitive control cycle, and

    a parallel circuit of an output capacitor (16) and a further switching element (18) is part of the control circuit arrangement and is connected in parallel with the LED arrangements (2.1, 2.2, 2.3, 2.i), wherein the switching element (18) is also controlled by the control unit (14) in order to achieve a faster discharge of the output capacitor (16), so that during sequential operation of the LED arrangements (2.1; 2.2; 2.3; 2.i) within a control cycle, the operating current (I_1; I_2; I_3; I_i) provided by the current source (12) changes from one clock phase (T_i) to a subsequent clock phase (T_i+1) within a short time, preferably immediately, from a higher current value for a first LED arrangement (2.1) of the LED arrangements (2.1; 2.2; 2.3; 2.i) to a lower current value for another LED arrangement (2.2; 2.3; 2.i) of the LED arrangements (2.1; 2.2; 2.3; 2.i).

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