Lighting circuit, in particular with LED light sources
First Claim
1. A lighting circuit, in particular for a motor vehicle light, comprising:
- at least one light source defined by a first voltage selection and susceptible to being driven by a first driving current;
a first selection circuit to identify said first voltage selection;
at least one light source defined by a second voltage selection and susceptible to being driven by a second driving current;
a second selection circuit to identify said second voltage selection;
wherein each of said first and second selection circuit includes at least one selection circuit element defined by a selection electric quantity having one of a plurality of predefined levels of electric quantity to which the same number of voltage selection levels of the light sources correspond;
an electronic control unit configured to detect said first and second voltage selection of the light source by said first and second selection circuit, and to regulate the driving current absorbed by the light source defined by the lower voltage selection, so that said driving current follows with a constant ratio the trend of the driving current absorbed by the light source defined by the higher voltage selection, the latter being taken as reference;
at least a first electronic lighting circuit board including at least said light source defined by the first voltage selection and said first selection circuit;
at least a second electronic lighting circuit board including at least said light source defined by the second voltage selection and said second selection circuit;
wherein the electronic control unit includes;
a current driver for each electronic lighting circuit board, said current driver being suitable for imposing a driving current of the respective light source;
a comparison circuit including a circuit suitable for comparing said selection electrical quantities, or electrical quantities derivable from said selection electrical quantities, so as to identify, on the basis of such comparison, the lighting circuit board having the at least one light source with the higher voltage selected;
a detection circuit for each of said electronic lighting circuit boards, wherein the detection circuit includes a circuit suitable for detecting a driving electric quantity of the light sources when powered with a power supply voltage; and
a regulation circuit including, for each of the electronic lighting circuit boards, a circuit regulator suitable for controlling the respective current driver in such a way that the driving current of one lighting circuit board follows the driving current of the other lighting circuit board with a constant ratio, and wherein said comparator circuit is connected to said current driver and to said circuit regulator in such a way that the lighting circuit with the higher voltage selection is driven by the comparator circuit with a reference driving current, and the driving current of the other lighting circuit board is regulated by the respective circuit regulator so as to follow said reference current with a constant ratio.
2 Assignments
0 Petitions
Accused Products
Abstract
A lighting circuit, in particular for a motor vehicle light, comprises at least one light source, particularly of the LED type, defined by a first voltage selection, a first selection circuit to identify said first voltage selection, at least one light source, particularly of the LED type, defined by a second voltage selection, and a second selection circuit to identify said second voltage selection. An electronic control unit configured to detect said first and second voltage selection of the light source, and to regulate the driving current absorbed by the light source defined by the lower voltage selection, so that said driving current follows with a constant ratio the trend of the driving current absorbed by the light source defined by the higher voltage selection, the latter being taken as reference.
13 Citations
20 Claims
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1. A lighting circuit, in particular for a motor vehicle light, comprising:
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at least one light source defined by a first voltage selection and susceptible to being driven by a first driving current; a first selection circuit to identify said first voltage selection; at least one light source defined by a second voltage selection and susceptible to being driven by a second driving current; a second selection circuit to identify said second voltage selection; wherein each of said first and second selection circuit includes at least one selection circuit element defined by a selection electric quantity having one of a plurality of predefined levels of electric quantity to which the same number of voltage selection levels of the light sources correspond; an electronic control unit configured to detect said first and second voltage selection of the light source by said first and second selection circuit, and to regulate the driving current absorbed by the light source defined by the lower voltage selection, so that said driving current follows with a constant ratio the trend of the driving current absorbed by the light source defined by the higher voltage selection, the latter being taken as reference; at least a first electronic lighting circuit board including at least said light source defined by the first voltage selection and said first selection circuit; at least a second electronic lighting circuit board including at least said light source defined by the second voltage selection and said second selection circuit; wherein the electronic control unit includes; a current driver for each electronic lighting circuit board, said current driver being suitable for imposing a driving current of the respective light source; a comparison circuit including a circuit suitable for comparing said selection electrical quantities, or electrical quantities derivable from said selection electrical quantities, so as to identify, on the basis of such comparison, the lighting circuit board having the at least one light source with the higher voltage selected; a detection circuit for each of said electronic lighting circuit boards, wherein the detection circuit includes a circuit suitable for detecting a driving electric quantity of the light sources when powered with a power supply voltage; and a regulation circuit including, for each of the electronic lighting circuit boards, a circuit regulator suitable for controlling the respective current driver in such a way that the driving current of one lighting circuit board follows the driving current of the other lighting circuit board with a constant ratio, and wherein said comparator circuit is connected to said current driver and to said circuit regulator in such a way that the lighting circuit with the higher voltage selection is driven by the comparator circuit with a reference driving current, and the driving current of the other lighting circuit board is regulated by the respective circuit regulator so as to follow said reference current with a constant ratio. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. An electronic control circuit board of light sources, where said light sources are mounted on at least two separate electronic lighting circuit boards, one of which being suitable for being implemented with the electronic control circuit board, wherein the light sources mounted on a first circuit board have a first voltage selection different from a second voltage selection of the light sources mounted on a second circuit board, comprising:
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a comparison circuit, including a circuit suitable for comparing selection electrical quantities, representative of the different voltage selections of the light sources, so as to identify, on the basis of the result of such comparison, the circuit board having the lighting sources with the higher voltage selection; and a regulation circuit including, for each of the electronic lighting circuit boards, a circuit regulator having input terminals which electric signals representative of the driving currents of the light sources of the lighting circuit boards are carried on, said circuit regulator being suitable for controlling respective lighting circuit boards in such a way that the driving current of one lighting circuit board is in a constant ratio with the driving current of another lighting circuit board, taken as reference, wherein said comparator circuit has output terminals, each connected to a respective regulator and to a respective current driver of the light sources in such a way that, depending on the level of the control signal present on said output terminals, said circuit regulators are enabled or disabled to control the respective lighting circuit board, the level of the control signal which disables the circuit regulators being suitable for controlling the respective current driver in such a way that they supply a reference driving current independent of the driving currents of the other lighting circuit boards. - View Dependent Claims (12, 13, 14, 15, 16, 17)
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18. A driver method of light sources, particularly of the LED type, where said light sources include at least a first light source defined by a first voltage selection and susceptible to being driven by a first driving current, and at least a second light source defined by a second voltage selection and susceptible to being driven by a second driving current, wherein
said first light source and a first selection circuit to identify said first voltage selection are placed on a first electronic lighting circuit board; -
said second light source and a second selection circuit to identify said second voltage selection are placed on a second electronic lighting circuit board; and wherein each selection circuit comprises at least one selection circuit element defined by a selection electric quantity having one of a plurality of predefined levels of electric quantity to which the same number of voltage selection levels of the light sources correspond; the method comprising the steps of; detecting said voltage selections of the light sources; identifying the highest voltage selection; and regulating the driving current of the other light source so that said driving current follows with a constant ratio the trend of the driving current absorbed by the light source defined by the higher voltage selection, the latter being taken as reference, imposing, for each electronic circuit board, a driving current of the respective light source using a driving current circuit; comparing said selection electrical quantities, or electrical quantities derivable from said selection electrical quantities by using a comparator circuit, so as to identify, on the basis of such comparison, the lighting circuit board having the at least one light source with the higher voltage selection; detecting a driving electric quantity of the light sources when powered with a power supply voltage by using a detection circuit, controlling the respective driving current circuit by using a regulation circuit in such a way that the driving current of one lighting circuit board follows the driving current of the other lighting circuit board with a constant ratio, and wherein the lighting circuit with the higher voltage selection is driven by the comparator circuit with a reference driving current, and the driving current of the other lighting circuit board is regulated by the regulation circuit so as to follow said reference current with a constant ratio. - View Dependent Claims (19)
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20. A driver method of light sources, particularly of the LED type, where said light sources comprise at least a first light source defined by a first voltage selection and susceptible to being driven by a first driving current, and at least a second light source defined by a second voltage selection and susceptible to being driven by a second driving current, the method comprising the steps of:
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associating to light sources having different voltage selections respective selection circuits; comparing selection electrical quantities generated by said selection circuits, or electrical quantities derivable from said selection electrical quantities, so as to identify, on the basis of such comparison, the at least one light source with the higher voltage selection; driving the lighting circuit board with the higher voltage selection with a reference driving current; and regulating the driving current of the other lighting circuit board so as to follow said reference current with a constant ratio.
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Specification