TECHNICAL FIELD
[0001] This invention belongs to the field of lighting devices installed in automotive vehicles,
and more specifically to the electronic assemblies used in these automotive lighting
devices.
STATE OF THE ART
[0002] Lighting devices installed in automotive vehicles usually comprise light sources
mounted on a printed circuit board (PCB). These light sources are usually controlled
to be selectively activated, so that different presentations may be achieved, depending
on the function required by the user.
[0003] This control has been traditionally made by means of micro-controllers (uC), such
as in document
US 2005/212459 A1, which are connected to each light source and performs a selective control so that
light sources are selectively activated or deactivated by the microcontroller in order
to achieve the required function.
[0004] The use of micro-controllers in lighting devices is therefore increasing, because
these dynamic functionalities are being demanded by the main automotive manufacturers.
However, these micro-controllers are expensive, and need to be programmed.
[0005] A different way of achieving these dynamic functions is therefore sought.
DESCRIPTION OF THE INVENTION
[0006] The invention provides an alternative solution for improving the aforementioned problem
by an electronic assembly according to claim 1 and an automotive lighting device according
to claim 8. Preferred embodiments of the invention are defined in dependent claims.
[0007] In an inventive aspect, the invention provides an electronic assembly for an automotive
lighting device, the electronic assembly comprising
a single power input;
a single communication input, intended to provide bi-directional communication with
a control centre;
a main driver element, comprising driver inputs arranged in direct bi-directional
communication with the communication input and further comprising driver discrete
outputs;
a first group of light sources, electrically fed by the power input,
a first power unit arranged between one driver discrete output and the first group
of light sources,
wherein the main driver element comprises a hardware finite-state machine configured
to provide a bi-directional communication between the communication input and the
first power unit.
[0008] A power unit is defined as any unit capable of drive electric loads at a constant
current. In particular embodiments, this element may be, e. g., a linear driver or
a DC/DC converter.
[0009] This electronic assembly may advantageously be used in an automotive lighting device
without any software programming. Hence, there is no need of updating or checking
a software, and there is no need for some auxiliary elements, such as a transceiver
and adapters, which were present in previous embodiments with micro-controllers. Further,
since a whole group of light sources are controlled by a single output of the main
driver element, more complex architectures are allowed.
[0010] In some particular embodiments, the electronic assembly further comprises a second
group of light sources electrically fed by the power input, wherein the main driver
element further comprises driver low current outputs and wherein the second group
of light sources are directly connected to driver low current outputs.
[0011] This main driver may also comprise traditional low current outputs for a direct control
of light sources which do not require an intermediate power step device.
[0012] In some particular embodiments, the electronic assembly further comprises a third
group of light sources electrically fed by the power input and a second power unit
arranged between one driver discrete output and the third group of light sources.
[0013] The fact that a group of light sources may be managed with an output of the main
driver element causes that
[0014] In some particular embodiments, the first power unit is a linear driver or a DC/DC
converter.
[0015] These elements are useful for managing the activation of high power light sources,
which cannot be managed directly by the main driver element.
[0016] In some particular embodiments, the main driver element is arranged as a current
sink, wherein the light sources are electrically arranged between the power input
and the main driver element.
[0017] In some particular embodiments, the main driver element further comprises a BUS configuration
memory and a measure and diagnosis units, and wherein
the hardware finite-state machine controls the driver outputs
the BUS configuration memory receives data directly from the communication input
the memory and diagnosis unit is arranged to receive data from the driver outputs
and transmit them to the hardware finite-state machine.
[0018] This particular arrangement of the main driver element allows a bi-directional communication
with the control centre of the vehicle without any software programmed element.
[0019] In some particular embodiments, the light sources are solid-state light sources,
such as light emitting diodes (LEDs).
[0020] The term "solid state" refers to light emitted by solid-state electroluminescence,
which uses semiconductors to convert electricity into light. Compared to incandescent
lighting, solid state lighting creates visible light with reduced heat generation
and less energy dissipation. The typically small mass of a solid-state electronic
lighting device provides for greater resistance to shock and vibration compared to
brittle glass tubes/bulbs and long, thin filament wires. They also eliminate filament
evaporation, potentially increasing the life span of the illumination device. Some
examples of these types of lighting comprise semiconductor light-emitting diodes (LEDs),
organic light-emitting diodes (OLED), or polymer light-emitting diodes (PLED) as sources
of illumination rather than electrical filaments, plasma or gas.
[0021] In a second inventive aspect, the invention provides a lighting device comprising
an electronic assembly according to the first inventive aspect.
[0022] This lighting device is particularly useful in automotive applications, for lighting
functionalities where a coordinated response is required, but may be obtained without
the use of an expensive programmed controller.
[0023] In some particular embodiments, the lighting device further comprises a first optical
element arranged to receive light from the plurality of light sources and to shape
the light into a light pattern projected outside the lighting device.
[0024] An optical element is an element that has some optical properties to receive a light
beam and emit it in a certain direction and/or shape, as a person skilled in automotive
lighting would construe without any additional burden.
[0025] In some particular embodiments, the optical element is at least one of a light guide,
a lens, a reflector or a collimator.
[0026] These optical elements are useful to manage the light produced by the plurality of
light sources and provide uniform output.
[0027] In some particular embodiments, the lighting device is a a turning indicator, a cornering
light, a fixed bending light or a daytime running lamp.
[0028] These lighting functionalities are typical to use a group of light sources to provide
the coordinated response.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] To complete the description and in order to provide for a better understanding of
the invention, a set of drawings is provided. Said drawings form an integral part
of the description and illustrate an embodiment of the invention, which should not
be interpreted as restricting the scope of the invention, but just as an example of
how the invention can be carried out. The drawings comprise the following figures:
Figure 1 shows an electronic assembly according to the invention.
Figure 2 shows a detailed scheme of an element of an electronic assembly according
to the invention.
Figure 3 shows a lighting device comprising an electronic assembly according to the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The example embodiments are described in sufficient detail to enable those of ordinary
skill in the art to embody and implement the systems and processes herein described.
It is important to understand that embodiments can be provided in many alternate forms
and should not be construed as limited to the examples set forth herein.
[0031] Accordingly, while embodiment can be modified in various ways and take on various
alternative forms, specific embodiments thereof are shown in the drawings and described
in detail below as examples. There is no intent to limit to the particular forms disclosed.
On the contrary, all modifications, equivalents, and alternatives falling within the
scope of the appended claims should be included. Elements of the example embodiments
are consistently denoted by the same reference numerals throughout the drawings and
detailed description where appropriate.
[0032] Unless otherwise defined, all terms (including technical and scientific terms) used
herein are to be interpreted as is customary in the art. It will be further understood
that terms in common usage should also be interpreted as is customary in the relevant
art and not in an idealised or overly formal sense unless expressly so defined herein.
[0033] In this text, the term "comprises" and its derivations (such as "comprising", etc.)
should not be understood in an excluding sense, that is, these terms should not be
interpreted as excluding the possibility that what is described and defined may include
further elements, steps, etc.
[0034] Figure 1 shows a first schematic view of an electronic assembly 1 according to the
invention. This electronic assembly 1 comprises
a single power input 2;
a single communication input 3, intended to provide bi-directional communication with
a control centre;
a main driver element 4; and
four groups of LEDs 5, 6, 7, 8, electrically fed by the power input 2.
[0035] The main driver element 4 comprises a driver input 40 arranged in direct bi-directional
communication with the communication input 3 and further comprises two types of driver
outputs: driver discrete outputs 41 and driver low current outputs 42.
[0036] Low current outputs 42 are arranged to feed two groups of low current LEDs 5, 6.
Due to the fact that these group of LEDs work with low current, they may be directly
managed by the main driver element 4, without the interposition of any intermediate
power stage.
[0037] Driver discrete outputs 41 are arranged to feed two groups of high power LEDs 7,
8. However, since the main driver element 4 is not able to provide a high amount of
power, intermediate power units 21, 22 are arranged between each driver discrete output
41 and each group of high power LEDs 7, 8.
[0038] In this particular example, the first intermediate power unit 21 is a linear driver
and the second intermediate power unit 22 is a DC/DC converter.
[0039] As may be seen in this figure, the main driver element 4 is arranged as a current
sink, because the groups of LEDs 5, 6, 7, 8 are electrically arranged between the
power input 2 and the main driver element 4.
[0040] Figure 2 shows a more detailed scheme of the main driver element 4 of figure 1. This
main driver 4 comprises the following
driver discrete outputs 41;
driver low current outputs 42;
a hardware finite-state machine 43 with a BUS configuration memory 44;
a measure and diagnosis unit 45;
[0041] The hardware finite-state machine 43 controls the driver outputs 41, 42, thus controlling
the activation and deactivation of the groups of LEDs. In turn, the BUS configuration
memory 44 receives data directly from the communication input 3, so that the hardware
finite state machine may act according to the information received.
[0042] Furthermore, the memory and diagnosis unit 45 is arranged to receive data from the
driver outputs 41, 42 and transmit them to the hardware finite-state machine 43, so
that this information is suitably transmitted to the communication input 3 and then
to the control centre.
[0043] Figure 3 shows a lighting device 10 comprising an electronic assembly 1 according
to the invention. This lighting device is a headlamp and is installed in an automotive
vehicle 100.
[0044] This lighting device comprises a projecting lens 9 which receives the light of the
plurality of LEDs (not seen) and shape it into a light pattern projected outside the
lighting device 10.
1. Electronic assembly (1) for an automotive lighting device (10), the electronic assembly
(1) comprising
a single power input (2);
a single communication input (3), intended to provide bi-directional communication
with a control centre;
a main driver element (4), comprising driver inputs (40) arranged in direct bi-directional
communication with the communication input and further comprising driver discrete
outputs (41);
a first group of light sources (7), electrically fed by the power input (2),
a first power unit (21) arranged between one driver discrete output (41) and the first
group of light sources (7),
wherein the main driver element (4) comprises a hardware finite-state machine (43)
configured to provide a bi-directional communication between the communication input
(3) and the first power unit (21).
2. Electronic assembly (1) according to claim 1, further comprising a second group of
light sources (5) electrically fed by the power input (2), wherein the main driver
element (4) further comprises driver low current outputs (42) and wherein the second
group of light sources (5) are directly connected to driver low current outputs (42).
3. Electronic assembly (1) according to any of the preceding claims, further comprising
a third group of light sources (8) electrically fed by the power input (2) and a second
power unit (22) arranged between one driver discrete output (41) and the third group
of light sources (8).
4. Electronic assembly (1) according to any of the preceding claims, wherein the first
power unit (21) is a linear driver or a DC/DC converter.
5. Electronic assembly (1) according to any of the preceding claims, wherein the main
driver element is arranged as a current sink, wherein the light sources are electrically
arranged between the power input (2) and the main driver element (4).
6. Electronic assembly (1) according to any of the preceding claims, wherein the main
driver element (4) further comprises a BUS configuration memory (44) and a measure
and diagnosis units (45), and wherein
the hardware finite-state machine (43) controls the driver outputs (41, 42);
the BUS configuration memory (44) receives data directly from the communication input
(3);
the memory and diagnosis unit (45) is arranged to receive data from the driver outputs
(41, 42) and transmit them to the hardware finite-state machine (43).
7. Electronic assembly (1) according to any of the preceding claims, wherein the light
sources are solid-state light sources, such as light emitting diodes or LEDs.
8. Automotive lighting device (10) comprising an electronic assembly (1) according to
any of the preceding claims.
9. Automotive lighting device (10) according to claim 8, further comprising a first optical
element (9) arranged to receive light from the plurality of light sources (5) and
to shape the light into a light pattern projected outside the lighting device.
10. Automotive lighting device (10) according to claim 9, wherein the optical element
(9) is at least one of a lens, a light guide, a reflector or a collimator.
11. Automotive lighting device (10) according to any of claims 8 to 10, the lighting device
(10) being a headlamp or a rear lamp.