LIGHTING UNIT, IN PARTICULAR HEADLIGHT, COMPRISING A LIGHT-EMITTING DIODE MATRIX AND A CONTROLLED POWER SOURCE

Abstract

A lighting unit having a light-emitting diode matrix and a controllable power source, in particular for a headlight. The light-emitting diode matrix is equipped with at least one first supply connection, a number m of first switches which have a first connection that is connected to the first supply connection, at least one second supply connection, a number n of second switches which have a second connection that is connected to the second supply connection, a number of m*n inorganic light-emitting diodes, a first connection of which is connected to a second connection of one of the first switches and a second connection of which is connected to a first connection of one of the second switches.

Claims

1. A lighting unit comprising: a controllable power source for a headlight; and a light-emitting diode matrix comprising: at least one first supply connection; a number m of first switches which have a first connection that is connected to the first supply connection; at least one second supply connection; a number n of second switches which have a second connection that is connected to the second supply connection; a number of m*n inorganic light-emitting diodes, a first connection of which is connected to a second connection of one of the first switches and a second connection of which is connected to a first connection of one of the second switches, wherein each second connection of a first switch is connected to a number n of the light-emitting diodes, wherein each first connection of a second switch is connected to a number m of the light-emitting diodes, wherein the light-emitting diodes which are connected to the second connection of the same first switch via the respective first connection of said light-emitting diodes are connected to the first connections of different switches of the second switches via the respective second connections of said light-emitting diodes, and wherein the light-emitting diodes which are connected to the first connection of the same second switch via the respective second connection of said light-emitting diodes are connected to the second connections of different switches of the first switches via the respective first connections of said light-emitting diode, and wherein the controllable power source is connected to the first supply connection and the second supply connection.

2. The lighting unit according to claim 1, wherein the light-emitting diodes are the same.

3. The lighting unit according to claim 1, wherein the first connection of the light-emitting diodes is an anode and the second connection of the light-emitting diodes is a cathode.

4. The lighting unit according to claim 1, wherein the first connection of the light-emitting diodes is a cathode and the second connection of the light-emitting diode is an anode.

5. The lighting unit according to claim 1, wherein the lighting unit includes a controller with which the first switches and the second switches of the light-emitting diode matrix are controllable, and wherein the controller is set up such that none, one or more of the first switches and in each case one of the second switches is closed during one of m*n consecutive sections of a period.

6. The lighting unit according to claim 5, wherein the controller is set up such that the sections of the period are of different lengths.

7. The lighting unit according to claim 5, wherein the controller is set up such that the length of the sections are changeable from period to period.

8. The lighting unit according to claim 5, wherein the controller is connected to a control connection of the controllable power source and that the controller is set up such that the current strength of the current supplied by the power source is adjustable for each section of the period.

9. A method for operating a lighting unit according to claim 5, wherein the controller controls the first switches and the second switches such that during one of the m*n sections of the period m*n none or at least one respective first switch and one respective second switch are closed.

10. The method according to claim 9, wherein the controller specifies a target current strength for each of the m*n sections and controls the power source in such a way that the target current strength of the power source is set for each of the m*n sections.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0018] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawing which is given by way of illustration only, and thus, is not limitive of the present invention, and wherein the sole figure illustrates an example embodiment, showing a cross-sectional view of an adjustment fitting with sealing of the eccentric receiving space.

DETAILED DESCRIPTION

[0019] The figure shows a circuit diagram of a light-emitting diode matrix of a lighting unit according to the invention.

[0020] The light-emitting diode matrix shown in the figure is provided for a motor vehicle headlight. The matrix has a first supply connection Vcc and a second supply connection GND, via which the light-emitting diode matrix can be connected to a controllable power source. The example has 32 inorganic light-emitting diodes LED2 to LED5, LED7 to LED10, LED12 to LED15, LED17 to LED20, LED22 to LED25, LED27 to LED30, LED32 to LED35, LED37 to LED40.

[0021] Each light-emitting diode LED2 to LED5, LED7 to LED10, LED12 to LED15, LED17 to LED20, LED22 to LED25, LED27 to LED30, LED32 to LED35, LED37 to LED40 has an anode as the first connection and a cathode as the second connection.

[0022] The first connection of each light-emitting diode is connected to the first supply connection Vcc via one of eight first switches Q1 to Q8. A first connection of each first switch Q1 to Q8 is connected to said first supply connection Vcc, while a second connection of the first switches Q1 to Q8 is connected to the first connections of four of the light-emitting diodes.

[0023] Via one of four second switches Q10 to Q13, the second connection of each light-emitting diode is connected to the second supply connection GND. A second connection of each second switch Q10 to Q13 is connected to said second supply connection GND, while a first connection of the second switches Q10 to Q13 is connected to the second connections of eight of the light-emitting diodes.

[0024] All light-emitting diodes which are connected to the second connection of the same first switch Q1 to Q8 via the respective first connection are connected via the respective second connections of said first connections of different second switches Q10 to Q13. Likewise, all light-emitting diodes which are connected to the first connection of the same second switches Q10 to Q13 via the respective second connection are connected via the respective first connections of said second connections of different first switches Q1 to Q8. The light-emitting diodes are therefore neither connected in parallel nor in series.

[0025] The first switches Q1 to Q8 as well as the second switches Q10 to Q13, which are transistors, have control connections via which they are connected to a controller, not shown. By programming the controller, it is possible to close and open switches Q1 to Q8, Q10 to Q13 in a desired way to produce light.

[0026] With the controller, not shown, it is possible to drive the first switches Q1 to Q8 and the second switches Q10 to Q13 to close and open in such a way that none, one or more LEDs connected to one of said second switches Q10 to Q13 are supplied with power from the controllable power source. Whether none, only one or more LEDs are supplied with power depends on whether none, only one or more first switches Q1 to Q8 are driven to close. If only a first switch is driven to close, the amount of the current can be individually adjusted by controlling the controllable power source.

[0027] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.