PRINTED CIRCUIT BOARD HAVING A PLURALITY OF ELECTRONIC COMPONENTS ARRANGED ON THE PRINTED CIRCUIT BOARD IN AT LEAST ONE GROUP

Abstract

A printed circuit board (1) with multiple electronic components (2, 2′, 2″, 2″′, 2″″) arranged on it in at least one group (G1, G2, G3), each of the electronic components (2, 2′, 2″, 2″′, 2″″) having a first and a second electrical component contact surface (3′, 3″) facing the printed circuit board (1), the component contact surfaces (3′, 3″) being connected with corresponding printed circuit board contact surfaces (6, 7, 8) arranged on the printed circuit board (1), successive electronic components (2, 2′, 2″, 2′″, 2″″) being connected in series to form a string, the string having a wave-shaped course, the electronic components (2, 2′, 2″, 2″′, 2″″) of the string being arranged on the printed circuit board (1) in the form of a matrix with at least two rows (Z1, Z2, Z3) and at least two columns (S1, . . . , S6), and the string alternately running up and down along columns (S1, . . . , S6) that are arranged next to one another.

Claims

1. A printed circuit board (1) with multiple electronic components (2, 2′, 2″, 2′″, 2″″) arranged on it in at least one group (G1, G2, G3), each of the electronic components (2, 2′, 2″, 2′″, 2″″) having a first and a second electrical component contact surface (3′, 3″) facing the printed circuit board (1), the component contact surfaces (3′, 3″) being connected with corresponding printed circuit board contact surfaces (6, 7, 8) arranged on the printed circuit board (1), successive electronic components (2, 2′, 2″, 2′″, 2″″) being connected in series to form a string, the string having a wave-shaped course, the electronic components (2, 2′, 2″, 2′, 2″″) of the string being arranged on the printed circuit board (1) in the form of a matrix with at least two rows (Z1, Z2, Z3) and at least two columns (S1, . . . , S6), and the string alternately running up and down along columns (S1, . . . , S6) that are arranged next to one another, successive electronic components (2, 2′, 2″, 2′″, 2″″) within a column always forming a series-connected vertical component pair by each vertical component pair being connected with a common vertical printed circuit board contact surface (7) associated with the vertical component pair, and the electronic components (2, 2″″) of every even-numbered column (S2, S4) of the top row (Z1) forming a horizontal component pair with the electronic component (2) of a following column (S3, S5) of the top row (Z1), and the electronic components (2″) of every odd-numbered column (S1, S3, S5) of the bottom row (Z2, Z3) forming a horizontal component pair with the electronic component (2′″) of the bottom row (Z2, Z3) of a following column (S2, S4, S6), or the electronic components (2) of every odd-numbered column (S1, S3, S5) of the top row (Z1) forming a horizontal component pair with the electronic component (2) of a following column (S2, S4, S6) of the top row, and the electronic components (2) of every even-numbered column (S2, S4) of the bottom row (Z2, Z3) forming a horizontal component pair with the electronic component (2) of the bottom row (Z2, Z3) of a following column (S3, S5), by every horizontal component pair being connected by means of a common horizontal printed circuit board contact surface (8) associated with the horizontal component pair, wherein every common printed circuit board contact surface (6, 7, 8) is associated with a conductor track (5), the common printed circuit board contact surfaces (6, 7, 8) being wider than the conductor track (5) and at least 1 mm wide, and the common printed circuit board contact surfaces (6, 7, 8) having an area of at least 2 mm.sup.2, preferably at least 4 mm.sup.2, especially preferably at least 10 mm.sup.2.

2. The printed circuit board (1) of claim 1, wherein a number n of electronic components (2) is associated with n+1 printed circuit board contact surfaces (6).

3. The printed circuit board (1) of claim 1, wherein the conductor tracks (5) run essentially parallel to one another.

4. The printed circuit board (1) of claim 1, wherein the conductor tracks (5) are brought out between horizontal printed circuit board contact surfaces that are arranged opposite one another and within the same row.

5. The printed circuit board (1) of claim 1, wherein the conductor tracks (5) are brought out exactly to one side of the printed circuit board (1).

6. The printed circuit board (1) of claim 3, wherein the conductor tracks (5) are brought out only before every second column.

7. The printed circuit board (1) of claim 1, wherein the electronic component (2) is a light-emitting electronic component, in particular a semiconductor device, especially preferably an LED, that preferably has an optical imaging system downstream of it.

8. The printed circuit board (1) of claim 1, wherein every electronic component (2) has a light-emitting surface (9), the light-emitting surface being at least 0.05 mm.sup.2, 0.2 mm.sup.2, 0.4 mm.sup.2, 0.5 mm.sup.2, or 1 mm.sup.2.

9. The printed circuit board (1) of claim 1, wherein the base area (4) of the electronic components is between 0.5 mm.sup.2 and 10 mm.sup.2.

10. The printed circuit board (1) of claim 1, wherein the length and width of the printed circuit board (1) are each at least 3 cm, 4 cm, 5 cm, or 6 cm.

11. The printed circuit board (1) of claim 1, wherein the electronic components (2) are arranged in exactly two rows.

12. The printed circuit board (1) of claim 1, wherein the electronic components (2) are arranged in at least three, four, or more than four rows.

13. The printed circuit board (1) of claim 1, wherein the electronic components (2) are arranged in at least three, four, or more than four columns.

14. The printed circuit board (1) of claim 1, wherein between five and ten columns of electronic components (2) are provided.

15. The printed circuit board (1) of claim 1, wherein at least two groups (G1, G2) are provided, the groups (G1, G2) being arranged rotated by 180° with respect to one another and the conductor tracks (5) always being brought out between the horizontal printed circuit board contact surfaces (8) of the row that is spaced farthest away from the opposite group (G1, G2).

16. The printed circuit board (1) of claim 1, wherein at least two groups, preferably four groups, are provided, the groups being arranged rotated by 90° to one another.

17. The printed circuit board (1) of claim 1, wherein the printed circuit board (1) is thermally connected with a heat sink, which preferably has a fan arranged on it.

18. A headlight, in particular a motor vehicle headlight, for producing a dynamic light pattern, this headlight comprising at least one printed circuit board (1) of claim 1, wherein the electronic components (2) are light-emitting electronic components (2), in particular, semiconductor devices, especially preferably LEDs or laser diodes.

19. The headlight according to claim 18, wherein the electronic components (2) are individually controllable.

20. A vehicle headlight system with two headlights, each headlight according to claim 18, wherein the headlight that is on the left when installed in a vehicle is configured to produce the left part of the light pattern on the road, and the headlight that is on the right when installed in the vehicle is configured to produce the right part of the light pattern, and wherein at least every LED light source, preferably every light-emitting diode of the two headlights is separately controllable.

Description

[0038] The invention is discussed in detail below on the basis of sample embodiments, which are shown in the figures and which are non-restrictive. The figures are as follows:

[0039] FIG. 1 is a schematic representation of a section of a printed circuit board with electronic components arranged in it according to the prior art;

[0040] FIG. 2 is a schematic representation of a sample electronic component over a printed circuit board;

[0041] FIG. 3 is a schematic representation of a section of a printed circuit board with electronic components arranged in it according to a first sample embodiment of the invention;

[0042] FIG. 4 is a schematic representation of a section of a printed circuit board with electronic components arranged in it according to a second sample embodiment of the invention; and

[0043] FIG. 5 is a schematic representation of a section of a printed circuit board with electronic components arranged in it according to a third sample embodiment of the invention.

[0044] Unless otherwise indicated, in the following discussion the same reference numbers designate the same features.

[0045] FIG. 1 is a schematic representation of a section of a printed circuit board 1 with electronic components 2 arranged in it (or 2′, 2″, 2′″ etc.—the right quotation mark “′” only serves to number the electronic components that all have the reference number 2 in common) in accordance with the prior art. For clarity, only three electronic components in the figure have been labeled with corresponding reference numbers. The electronic components 2 typically have a positive and a negative terminal (or a cathode and an anode or a collector and an emitter, source, or drain, etc.), which are connected with corresponding component contact surfaces 3′ and 3″ (see FIG. 2).

[0046] A sample electronic component 2 such as can be used in the prior art, but also in the invention, is shown in FIG. 2. It shows component contact surfaces 3′, 3″, which are opposite one another and arranged on a base area 4 of the electronic component 2. The electronic component 2 is arranged over a section of a printed circuit board 1, this section of the printed circuit board 1 having printed circuit board contact surfaces 6′ and 6″ corresponding to the component contact surfaces 3′ and 3″.

[0047] The electronic components 2 in FIG. 1 are connected in series along a string. To accomplish this, the electronic components 2 are connected with conductor tracks 5, which make contact with the corresponding component contact surfaces (not shown in FIG. 1), by a first conductor track 5′ making contact with a negative terminal of a first electronic component 2′, a second conductor track 5″ making contact with the positive terminal of the first electronic component 2′ and the negative terminal of the following electronic component 2″, a third conductor track 5′″ making contact with the positive terminal of the second electronic component 2″ and the negative terminal of a third electronic component 2′″, etc. This achieves a series connection of the components 2 that are shown, the insulating sections lying between the conductor tracks 5 filling most of the surface of the section of the printed circuit board that is shown. In such an arrangement, only a relatively poor cooling of the electronic components 2 can be achieved by means of the printed circuit board 1 and/or cooling elements arranged on the printed circuit board 1, for which reason the power density of the electronic components 2 that can be put on the printed circuit board 1 is relatively small.

[0048] FIG. 3 is a schematic representation of a section of a printed circuit board 1 with electronic components 2 arranged in it according to a first sample embodiment of the invention. This figure schematically represents the printed circuit board 1 with multiple electronic components 2 arranged in a group G2 on the printed circuit board 1 and [upstream and] downstream sections of analogous groups G1 and G3. The electronic components 2 arranged within this group G2 correspond to the components 2 in FIG. 2, and therefore have first and second electrical component contact surfaces 3′ and 3″ facing the printed circuit board 1, which are connected with corresponding printed circuit board contact surfaces 6′, 6″, 6′″ etc. arranged on the printed circuit board 1, successive electronic components 2 forming a string by series connection, the string having a wave-shaped (or meandering) course, the electronic components 2 of the string being arranged on the printed circuit board 1 in the form of a matrix with at least two rows Z1 and Z2 and at least two columns (in the first sample embodiment, the group G2 has six columns S1 through S6), and the string alternately running up and down along columns S1 through S6 that are arranged next to one another.

[0049] In the sample embodiment shown, the group G2 has exactly six columns S1 through S6 and two rows Z1 and Z2, in which the electronic components 2 are arranged. For clarity, only the first four electronic components of a string have been labeled with reference numbers, namely the reference numbers 2′ for the first electronic component of the string, 2″ for the following electronic component, which is arranged in the lower row Z2 of the same column S1, and the following electronic component 2′″ connected in series with it, and the electronic component 2″″ that is in turn connected with the latter, etc. Therefore, in the first column S1 the string runs down from the first electronic component 2′ to the second electronic component 2″, successive electronic components 2 arranged within a column S each forming, as can clearly be seen, a vertical component pair connected in series, each vertical component pair being connected with a common vertical printed circuit board contact surface 7 associated with the vertical component pair. The transition of the string from one column to a following column takes place through so-called horizontal component pairs, which are formed through adjacent electronic components 2 arranged within the same row. These are connected with a common horizontal printed circuit board contact surface 8.

[0050] Here the term “vertical” does not necessarily specify the geometric orientation of the circuit board contact surface 7. Instead, it only describes the connection of an electronic component 2 arranged above to a following electronic component 2 arranged below within the same string. In general, not every “field” that is associated with rows and columns need be occupied with a component 2. It is also possible for the orientation of the rows and columns to one another to deviate from an orthogonal structure. In the same way, individual rows and/or columns could be slightly offset. Preferably, the vertical printed circuit board contact surface can have a geometric form of a rectangle that extends farther in a vertical direction than in a horizontal direction. In addition, the directions “vertical” and “horizontal” should only be understood with regard to the printed circuit board 1, it being possible for the coordinate system for defining a horizontal and vertical axis to be defined in any way with regard to the printed circuit board 1. In the same way, it is possible for the printed circuit board 1 to be installed in any location, for example in a vehicle headlight.

[0051] In the sample embodiment shown, the electronic components 2 of every even-numbered column (in this example S2, S4) of the top row (Z1) are connected with the electronic component 2 of a following column (S3 and S5, top row) and form a horizontal component pair. The electronic components 2 of every odd-numbered column (here S3, S5) of the bottom row (here Z2) are connected with the electronic component 2 of the bottom row of a following column and form a horizontal component pair. This generally does not apply for the first and last electronic component 2 of the string.

[0052] Of course the individual rows and columns can also be linked in the opposite way. In the example according to FIG. 3, the string first runs down the column S1, then through the horizontal component pair of the lower row Z2 to the second column S2, where the string runs upwards in the direction of row Z1, where it then again runs down the following column S3, etc. Alternatively, the string could, in the same way, first run up the column S1 and then lead through a horizontal component pair into the column S2 and run down in it, etc. The mentioned electronic components 2 of one column are, as was already mentioned, connected to the following column through a horizontal component pair, which is associated with a common horizontal printed circuit board contact surface 8. This arrangement of the electronic components 2 creates a matrix, each field of which preferably has an electronic component 2 arranged in it. Therefore, in the sample embodiment shown, the group G2 has twelve electronic components 2 arranged within it. The components need not necessarily be arranged in the rows and columns so that they line up with one another, but rather can be completely offset to one another.

[0053] In the sample embodiments of the invention, the electronic components are LEDs, each of which has a light exit surface 9, the light exit surfaces 9 of adjacent electronic components 2 in the sample embodiment shown being identically spaced apart from one another.

[0054] In the sample embodiment according to FIG. 3 it can also be seen that every printed circuit board contact surface 6 (both the vertical and the horizontal printed circuit board contact surfaces 7 and 8 are generally referenced as printed circuit board contact surfaces 6) has a conductor track 5 associated with it. Moreover, a number of (n) electronic components 2 is associated with (n+1) printed circuit board contact surfaces 5. In addition, the conductor tracks 5 run essentially parallel to one another and are brought out between horizontal printed circuit board contact surfaces 8 that are opposite one another. The term “opposite one another” is understood to mean horizontal printed circuit board contact surfaces 8, which preferably are arranged in the same row and successive columns. This allows the conductor tracks 5 to be brought out exactly to one side of the printed circuit board 1. In addition, the conductor tracks 5 are only brought out before every second column. In the example shown the so-called brought-out conductor tracks 5 are generally the conductor tracks (5″, 5′″, 5″″) that are brought out between the horizontal printed circuit board contact surfaces 8. As can be seen in FIG. 3, three conductor tracks (5″, 5′″, 5″″) are brought out upward between the printed circuit board contact surfaces 6′ of the first electronic component 2′ and the printed circuit board contact surface 8, which is connected with the fourth electronic component 2″″ of the string's second group. The transition of the columns S2 and S3 has no conductor tracks 5 that are brought out upward or downward, which allows the formation of a common horizontal printed circuit board contact surface 8, and therefore the conductor tracks only have to be brought out before every second column. The arrangement shown allows conductor tracks to be shifted to the next transition, namely between columns S3 and S4, which on the one hand reduces the total number of conductor tracks that need to be brought out, and moreover allows their spatial arrangement to be optimized. This also allow especially large dimensioning of the printed circuit board contact surfaces 6.

[0055] The printed circuit board contact surfaces 6 have an area of at least 2 mm.sup.2, preferably at least 4 mm.sup.2, especially preferably at least 10 mm.sup.2. The light-emitting surface 9 of the electronic component 2 is preferably at least 0.3 mm.sup.2, preferably 0.4 mm.sup.2 or at least 0.5 mm.sup.2. The base area of an electronic component 2 is for example between 0.5 mm.sup.2 and 10 mm.sup.2. The printed circuit board 1 can have a length and/or a width of at least 3 cm, 4 cm, 5 cm, or 6 cm.

[0056] FIG. 4 is a schematic representation of a section of a printed circuit board 1 with electronic components 2 arranged in it according to a second sample embodiment of the invention. The electronic components 2 in it are again arranged in six columns S1 through S6, three rows Z1 through Z3 being provided. Consequently, in the arrangement shown the group G2 has eighteen (6×3) electronic components 2 arranged in it. This increases the number of conductor tracks 5, which are, analogous to the first embodiment according to FIG. 3, only brought out upward in the already described way only before every second column. The directions up and down only relate to the arrangement on a printed circuit board 1.

[0057] FIG. 5 is a schematic representation of a third sample embodiment of the invention, which illustrates a section of a printed circuit board 1 with electronic components 2 arranged in it. It essentially represents an arrangement that can be organized into two groups G1 and G2, which are opposite one another. The groups G1 and G2 have two rows and six columns. Every group has twelve electronic components 2. The groups are rotated by an angle of 180° to one another, the asymmetry of the electronic components adapting the horizontal printed circuit board contact surfaces 8 to one another so that they correspond to one another and complement one another, which can achieve a uniform spacing between the groups G1 and G2 and between all light-emitting surfaces 9 of the components 2 arranged within the two groups G1 and G2.

[0058] In the embodiments shown, the spacings of the light-emitting surfaces 9 of adjacent electronic components 2 remain constant throughout. Alternatively, of course it would also be possible to vary the spacings, which makes it possible to influence the resolution of individual segments of a light pattern in a targeted manner.

[0059] All the mentioned inventive embodiments have especially advantageous cooling properties, and are simple and economical to produce. In consideration of this teaching, the invention can be modified in any way by the person skilled in the art, and therefore it is not limited to the embodiments shown. It is also possible to take individual aspects of the invention or the embodiments shown and combine them with one another. What is essential are the ideas on which the invention is based, which can be realized in diverse ways by the person skilled in the art who knows this description, but nevertheless remain the same.