CN111713180A

CN111713180A - Illumination system comprising a dimmable engine

Info

Publication number: CN111713180A
Application number: CN201880089940.9A
Authority: CN
Inventors: 邱怡峰
Original assignee: Bright Sharp LLC
Current assignee: Bright Sharp LLC
Priority date: 2017-12-20
Filing date: 2018-12-20
Publication date: 2020-09-25
Anticipated expiration: 2038-12-20
Also published as: JP2021507473A; TWI764228B; JP6942257B2; CN111713180B; WO2019126583A1; TW202044923A; CN115297587A; TW201933644A; EP3729912A1; TWI704707B; KR102501197B1; KR20200098660A

Abstract

An illumination system is disclosed that provides a control signal interface configured to provide a voltage control signal via a control channel. There is provided a light engine comprising: the apparatus includes a first signal generator configured to provide a first Pulse Width Modulation (PWM) signal based on a control signal via a first channel, a second signal generator configured to provide a second PWM signal based on the control signal via a second channel, and a third signal generator configured to provide a third PWM signal based on the first PWM signal and the second PWM signal via a third channel.

Description

Illumination system comprising a dimmable engine

Technical Field

The present disclosure relates generally to light emitting devices, and more particularly, to illumination systems including light engines.

Background

Light emitting diodes ("LEDs") are commonly used as light sources in a variety of applications. For example, LEDs are more energy efficient than traditional light sources, providing much higher energy conversion efficiency than incandescent and fluorescent lamps. In addition, compared with a traditional light source, the LED radiates less heat to an irradiation area, and the control range of brightness, emission color and spectrum is wider. These characteristics make LEDs an excellent choice for a variety of lighting applications, from indoor lighting to automotive lighting.

Disclosure of Invention

An illumination system is disclosed that provides a control signal interface configured to provide a voltage control signal via a control channel. There is provided a light engine comprising: a first signal generator configured to provide a first Pulse Width Modulation (PWM) signal based on a control signal via a first channel, a second signal generator configured to provide a second PWM signal based on the control signal via a second channel; and a third signal generator configured to provide a third PWM signal based on the first PWM signal and the second PWM signal via a third channel.

Drawings

The drawings described below are for illustration purposes only. The drawings are not intended to limit the scope of the present disclosure. In various embodiments, like reference numerals shown in the figures represent like parts.

FIG. 1 is a schematic diagram of an illumination system according to aspects of the present disclosure;

fig. 2 is a schematic diagram of an example of a PWM signal generator according to aspects of the present disclosure;

fig. 3 is a diagram of an example of a PWM signal generated by the PWM signal generator of fig. 2, in accordance with aspects of the present disclosure;

fig. 4 is a graph illustrating a response of the PWM generator of fig. 2 to a change in control voltage, in accordance with aspects of the present disclosure;

fig. 5 is a diagram of an example of an illumination system according to aspects of the present disclosure;

fig. 6A is a graph illustrating a relationship between different PWM signals according to aspects of the present disclosure;

fig. 6B is a graph illustrating a relationship between different PWM signals according to aspects of the present disclosure, according to aspects of the present disclosure;

fig. 7 is a graph illustrating the operation of the illumination system of fig. 5 according to one possible configuration;

fig. 8 is a graph illustrating the operation of the illumination system of fig. 5 according to another possible configuration;

fig. 9 is a graph illustrating a relationship between different control signals in the illumination system of fig. 5, according to aspects of the present disclosure;

FIG. 10 is a flow chart of an example of a process according to aspects of the present disclosure;

FIG. 11 is a top view of an electronic board of an integrated LED lighting system according to one embodiment;

FIG. 12A is a top view of an electronic board with an array of LEDs attached to a substrate at an LED device attachment area, in one embodiment;

FIG. 12B is a diagram of one embodiment of a dual channel integrated LED illumination system with electronic components mounted on both surfaces of the circuit board;

FIG. 12C is a diagram of an embodiment of an LED lighting system in which the LED array is located on an electronic board separate from the driver and control circuitry;

fig. 12D is a block diagram of an LED lighting system with an array of LEDs and some of the electronics on the electronics board separate from the driver circuit;

fig. 12E is a diagram illustrating an example LED lighting system of a multi-channel LED driver circuit;

FIG. 13 is a diagram of an example application system;

fig. 14A is a diagram showing an LED device; and

fig. 14B is a diagram showing a plurality of LED devices.

Detailed Description

Examples of different light illumination systems and/or light emitting diode ("LED") implementations are described more fully below with reference to the accompanying drawings. These examples are not mutually exclusive and features found in one example may be combined with features found in one or more other examples to achieve further implementations. Therefore, it should be understood that the examples shown in the drawings are provided for illustrative purposes only and are not intended to limit the present disclosure in any way. Like numbers refer to like elements throughout.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms may be used to distinguish one element from another. For example, a first element could be termed a second element, and a second element could be termed a first element, without departing from the scope of the present invention. As used herein, the term "and/or" can include any and all combinations of one or more of the associated listed items of the associated listed item.

It will be understood that when an element such as a layer, region or substrate is referred to as being on or extending onto another element, it can be directly on or extend directly onto the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or extending "directly onto" another element, there are no intervening elements present. It will also be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element and/or be connected or coupled to the other element via one or more intermediate elements. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present between the element and the other element. It will be understood that these terms are intended to encompass different orientations of the element in addition to any orientation depicted in the figures.

Relative terms, such as "below," "above," "below," "horizontal" or "vertical," may be used herein to describe one element, layer or region's relationship to another element, layer or region as illustrated in the figures. It will be understood that these terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures.

Further, whether the LEDs, LED arrays, electrical components, and/or electronic components are housed on one, two, or more electronic boards may also depend on design constraints and/or applications.

Semiconductor Light Emitting Devices (LEDs) or optical power emitting devices, such as devices that emit Ultraviolet (UV) or Infrared (IR) optical power, are among the most efficient light sources currently available. These devices (hereinafter "LEDs") may include light emitting diodes, resonant cavity light emitting diodes, vertical cavity laser diodes, edge emitting lasers, and the like. For example, LEDs may be attractive candidates for many different applications due to their compact size and lower power requirements. For example, they may be used as light sources (e.g., flash and camera flash) for hand-held battery-powered devices such as cameras and cell phones. For example, they may also be used for automotive lighting, head-up display (HUD) lighting, horticulture lighting, street lighting, video torches, general lighting (e.g., home, shop, office and studio lighting, theater/stage lighting, and architectural lighting), Augmented Reality (AR) lighting, Virtual Reality (VR) lighting, display backlighting, and IR spectroscopy. A single LED may provide less light than an incandescent light source, and thus, a multi-junction device or LED array (such as a monolithic LED array, a micro LED array, etc.) may be used in applications where higher brightness is desired or required.

Adjustable lighting is highly desirable in consumer and commercial lighting. Adjustable illumination systems are typically capable of changing their color and brightness independently of each other. According to aspects of the present disclosure, a tunable illumination system is disclosed that splits a single channel output into three by current control and/or time division multiplexing techniques. More specifically, the tunable optical system may divide the input current into three Pulse Width Modulation (PWM) channels. The respective duty cycles of the PWM channels may be adjusted based on a control signal received via the control signal interface. The control signal interface may comprise a switch and/or other circuitry which is manipulated by the user when the user wants to change the color of the light output by the illumination system.

According to aspects of the present disclosure, there is disclosed an illumination system comprising: a first signal generator configured to generate a first Pulse Width Modulation (PWM) signal based on a first control signal; a second signal generator configured to generate a second PWM signal based on a voltage difference between the reference signal and the first control signal; a third signal generator configured to generate a third PWM signal based on the first PWM signal and the second PWM signal, the third PWM signal having a different duty ratio from at least one of the first PWM signal and the second PWM signal; a first Light Emitting Diode (LED) powered using a first PWM signal, the first LED configured to emit a first type of light; a second LED powered using a second PWM signal, the second LED having a second CCT, the second LED configured to emit a second type of light; and a third LED powered using a third PWM signal, the third LED configured to emit a third type of light.

According to aspects of the present disclosure, a method for operating a lighting system is disclosed, comprising: generating a first Pulse Width Modulation (PWM) signal based on a first control signal; generating a second PWM signal based on a difference between the reference signal and the first control signal; generating a third PWM signal based on the first PWM signal and the second PWM signal, the third PWM signal having a different duty cycle than at least one of the first PWM signal and the second PWM signal; controlling a first light emitting diode based on a first PWM signal, the first LED configured to output a first type of light; controlling a second LED based on the second PWM signal, the second LED configured to output a second type of light; and controlling a third LED based on the third PWM signal, the third LED configured to output a third type of light.

Fig. 1 is a diagram of an example of an illumination system 100 according to aspects of the present disclosure. The illumination system 100 may comprise a control signal interface 110, a light device 120 and a light engine 130. In operation, the lighting system 100 may receive user input via the control signal interface 110 and change the color of the light output by the light device 120 based on the input. For example, if a first user input is received, the light device 120 may output light having a first color. Conversely, if a second user input is received, the light device 120 may output light having a second color that is different from the first color. In some implementations, a user may provide input to the illumination system by turning a knob or moving a slider that is part of the control signal interface 110. Additionally or alternatively, in some implementations, the user may provide input to the lighting system by using his or her smartphone and/or another electronic device to send an indication of a desired color to the control signal interface 110.

The control signal interface 110 may include any suitable type of circuit or device configured to generate the voltage signal CTRL and provide the voltage signal CTRL to the light engine 130. Although in this example the control signal interface 110 and the light engine 130 are depicted as separate devices, alternative implementations are possible in which the control signal interface 110 and the light engine 130 are integrated together in the same device. For example, in some implementations, the control signal interface 110 may include a potentiometer coupled to a knob or slider that is operable to generate the control signal CTRL based on the position of the knob (or slider). As another example, the control signal interface may include a wireless receiver (e.g., a bluetooth receiver, a Zigbee receiver, a Wi-Fi receiver, etc.) operable to receive one or more data items from a remote device (e.g., a smartphone or a Zigbee gateway) and output the control signal CTRL based on the data items. In some implementations, the one or more data items may include a number identifying a desired Correlated Color Temperature (CCT) to be output by light apparatus 120.

The light device 120 may include a light source 122 (e.g., warm white), a light source 124 (e.g., cool white), and a light source 126 (e.g., neutral white). The light source 122 (e.g., warm white light) may include one or more LEDs configured to output white light having a CCT of about 2700K. The light source 124 (e.g., cool white light) may include one or more LEDs configured to output white light having a CCT of approximately 6500K. The light source 126 (e.g., neutral white) may include one or more LEDs configured to output white light having a CCT of about 4000K.

The light engine 130 may be configured to provide power to the light device 120 through three different channels. More specifically, the light engine 130 may be configured to: providing a first PWM signal PWR1 to the light source 122 (e.g., warm white) through a first channel; providing a second PWM signal PWR2 (e.g., cool white) to the light source 124 through a second channel; and provides the third PWM signal PWR3 to the light source 126 (e.g., neutral white) via the third channel. Signal PWR1 may be used to power a warm white light source whose duty cycle may determine the brightness of the warm white light source. Signal PWR2 may be used to power a cool white light source whose duty cycle may determine the brightness of the cool white light source. Signal PWR3 may be used to power a neutral white light source whose duty cycle may determine the brightness of the neutral white light source. In operation, the dimmable engine may vary the relative magnitudes of the duty cycles of the signals PWR1, PWR2, and PWR3 to adjust the respective brightness of each of the light sources 122 and 126. It will be readily appreciated that varying the respective intensities of the light sources 122-126 may cause the output of the light device 120 to change color (and/or CCT). As described above, the light output of the light device 120 may be a combination (e.g., a mixture) of the light emissions produced by the light sources 122 and 126.

According to aspects of the present disclosure, the light engine 130 may include any suitable type of electronic device and/or electronic circuitry configured to generate the signals PWR1, PWR2, and PWR 3. Although in the present example, signals PWR1-PWR3 are PWM signals, alternative implementations are possible in which signal PWR1 is a current signal, a voltage signal, and/or any other suitable type of signal. Furthermore, although in the present example, the light sources 122 and 126 are white light sources, alternative implementations are possible in which the light sources 122 and 126 are each configured to emit light of a different color. For example, light source 122 may be configured to emit red light, light source 126 may be configured to emit green light, and light source 124 may be configured to emit blue light.

Fig. 2 is a schematic diagram of an example of a PWM generator 200 according to aspects of the present disclosure. PWM generator 200 may comprise any suitable type of PWM generator. In some implementations, the PWM generator 200 may include a power up terminal 210, a ground terminal 220, a control terminal 230, and an output terminal 240. In operation, the PWM generator 200 may receive power at the power-up terminal 210 and a voltage control signal VCTRL at the control terminal 230. Based on the control signal VCTRL, the PWM generator 200 may generate a PWM signal and output the PWM signal from the output terminal 240.

Fig. 3 is a graph illustrating an example of a PWM signal that may be generated by PWM generator 200. The PWM signal may have a period P and a pulse width W. The duty ratio of the PWM signal may be a proportion of each period P in which the PWM signal is on (e.g., high), and may be described by the following equation 1:

equation 1

Fig. 4 is a graph illustrating the response of the PWM generator 200 according to aspects of the present disclosure. As shown, when the control signal VCTRL has a first value (e.g., about 0V), the duty cycle of the PWM signal generated by the PWM generator 200 may be 100%, and when the control signal VCTRL has a second value Vc, the PWM generator 200 may be deactivated. Although not shown in fig. 4, in some implementations, the PWM generator 200 may be configured to set the duty cycle of the PWM signal to 100% when the value of the control signal VCTRL is within a predetermined range (e.g., 0V-0.4V). Configuring the PWM generator 200 in this manner may ensure that it is always possible to output a PWM signal with a 100% duty cycle, since it may not always be possible to obtain a control signal of exactly 0V in an analog circuit. According to aspects of the present disclosure, when the PWM generator is deactivated, it may be considered to generate a PWM signal having a duty cycle of 0%. According to the present disclosure, the value Vc may be referred to as the off-voltage of the PWM generator. The value Vc may depend on the internal design of the PWM generator 200. Any suitable value of Vc may be obtained by one of ordinary skill in the art, depending on design specifications

Fig. 5 is a circuit diagram of an example of an illumination system 500, which uses a PWM generator, such as PWM generator 200, as one of its building blocks. As shown, the illumination system 500 may include a light fixture 510, a control signal interface 520, and a light engine 530.

Light device 510 may include light source 512, light source 514, and light source 516. Each light source may include one or more respective LEDs. For example, the light source 512 may include one or more Light Emitting Diodes (LEDs) configured to generate a first type of light. Light source 514 may include one or more LEDs configured to generate a second type of light. The light source 516 may include one or more LEDs configured to generate a third light. The three types of light may differ from each other in one or more of wavelength, Color Rendering Index (CRI), Correlated Color Temperature (CCT), and/or color. In some implementations, the first type of light may be warm white light, the second type of light may be cool white light, and the third type of light may be neutral white light. Additionally or alternatively, in some implementations, the first type of light may be red light, the second type of light may be green light, and the third type of light may be blue light.

According to the present example, the light device 510 may be arranged to generate tunable white light by mixing the respective outputs of each of the

light sources

512 and 516. In such an example, the light source 512 may be configured to emit warm white light having a CCT of about 2700K; the light source 514 may be configured to emit cool white light having a CCT of about 6500K; and the light source 516 may be configured to emit neutral white light having a CCT of about 4000 CCT. As described above, the output of the optical device 510 may be a composite optical output produced as a result of the intermixing of the emissions from the

light sources

512 and 516. The CCT of the composite light output may be changed by changing the respective brightness of each light source based on a control signal VCRL1, which control signal VCRL1 is generated by the control signal interface 520 and provided via the first channel 521.

The control signal interface 520 may include any suitable type of circuitry or device configured to generate the voltage control signal VCTRL1 and provide the control signal VCTRL1 to the light engine 530. Although in this example, the control signal interface 520 and the light engine 530 are depicted as separate devices, alternative implementations are possible in which the control signal interface 520 and the light engine 530 are integrated together in the same device. For example, in some implementations, the control signal interface 520 may include a potentiometer coupled to a knob or slider that is operable to generate the control signal VCTRL1 based on a position of the knob (or slider). As another example, the control signal interface may include a wireless receiver (e.g., a bluetooth receiver, a Zigbee receiver, a Wi-Fi receiver, etc.) operable to receive one or more data items from a remote device (e.g., a smartphone or a Zigbee gateway) and output the control signal VCTRL1 based on the data items. As another example, control signal interface 520 may include an autonomous or semi-autonomous controller configured to generate control signal VCTRL1 based on various control criteria. Those control criteria may include one or more of a time of day, a current date, a current month, a current season, etc.

The light engine 530 may be a three channel light engine. The light engine 530 may be configured to provide power to each of the light sources 512-516 through different

respective channels

522, 523, and 524. The light engine 530 may include a current source 532, a voltage regulator 534, and a reference voltage generator 536. As shown, the voltage regulator 534 may be configured to generate a voltage VDD for powering various components of the light engine 530. Reference voltage generator 536 may be configured to generate a reference voltage signal VREF. The effect of signal VREF on the operation of light engine 530 is discussed further below.

The light engine 530 may operate to drive the light source 512 by using a first PWM signal PWR1, which is provided to the light source 512 by a first channel 522, PWR 1. The signal PWR1 may be generated by using the first signal generator GEN 1525 and the first switch SW 1. The generator GEN 1525 may be the same as or similar to the PWM generator 200 discussed with reference to fig. 2, and it may have a cut-off voltage Vc₁. Switch SW1 may be a MOSFET transistor. Light source 512 may be connected to current source 532 across the drain-source of MOSFET transistor SW1, and the gate of MOSFET transistor SW1 may be arranged to receive PWM signal VGATE1 generated by signal generator GEN 1525. It will be readily appreciated that this arrangement may result in switch SW1 imparting the same or similar duty cycle on signal PWR1 as signal VGATE 1. As shown in FIG. 3, the duty cycle of signal VGATE1 may depend on the amplitude of control signal VCTRL1 (e.g.Level).

The light engine 530 may operate to drive the light source 514 by using the second PWM signal PWR2, which is provided to the light source 514 through the second channel 523, the second PWM signal PWR 2. The signal PWR2 may be generated by using the second signal generator GEN 2526 and the second switch SW 2. The generator GEN 2526 may be the same as or similar to the PWM generator 200 discussed with reference to fig. 2, and it may have a cut-off voltage Vc₂. Cut-off voltage Vc of signal generator GEN 2526₂Can be connected with the cut-off voltage Vc of the signal generator GEN 1525₁The same or different. Switch SW2 may be a MOSFET transistor. The light source 514 may be connected to the current source 532 across the drain-source of the MOSFET transistor SW2, and the gate of the MOSFET transistor SW2 may be arranged to receive the PWM signal VGATE2 generated by the signal generator GEN 2526. It will be readily appreciated that this arrangement may result in switch SW2 imparting the same or similar duty cycle on signal PWR2 as signal VGATE 2. As shown in fig. 3, the duty cycle of the signal VGATE2 may depend on the amplitude (e.g., level) of the voltage control signal VCTRL 2.

The control signal VCTRL2 may be a voltage signal. Further, as described above, the signals VCTRL1 and VREF may also be voltage signals. In this regard, the control signal VCTRL2 may be generated by subtracting the voltage of the first control signal VCTRL1 from the voltage of the reference signal VREF. For example, when the reference signal VREF is 10V and the control signal VCTRL1 is 3V, the control signal VCTRL2 may be equal to 7V. The control signal VCTRL2 may be generated using a voltage subtraction circuit SUB 1. The subtraction circuit SUB1 may include an operational amplifier (opamp) 540 configured to operate as a voltage subtractor. Further, the subtraction circuit SUB1 may include

resistors

552, 554, 556, and 558. Both

resistors

552 and 554 may have a resistance R2. Both resistors 556 and 558 may have a resistance R1. Resistor R2 may be the same as or different from resistor R1. As shown, a resistor 552 may be disposed between the output and the inverting input of the operational amplifier 540. Resistor 554 may be coupled between the non-inverting input of operational amplifier 540 and ground. Resistor 556 may be coupled between the inverting terminal of operational amplifier 540 and control signal interface 520. Resistor 558 may be coupled between the non-inverting terminal of operational amplifier 540 and control reference voltage generator 536. In operation, operational amplifier 540 may: (i) receive the control signal VCTRL1 as a first input, (ii) receive the reference signal VREF as a second input, and generate the control signal VCTRL2 based on the control signal VCTRL1 and the reference signal VREF. The amplitude of the control signal VCTRL2 may be described by equation 2 below:

equation 2

The light engine 530 may operate to drive the light source 516 by using a third PWM signal PWR3, which third PWM signal PWR3 is provided to the light source 516 through the third channel 524. The signal PWR3 may be generated by using the third signal generator GEN3 and the third switch SW 3. Switch SW2 may be a MOSFET transistor. The light source 516 may be connected to the current source 532 across the drain-source of the MOSFET transistor SW3, and the gate of the MOSFET transistor SW3 may be arranged to receive the PWM signal VGATE3 generated by the signal generator GEN 3. It will be readily appreciated that this arrangement may result in switch SW3 imparting the same or similar duty cycle on signal PWR3 as signal VGATE 3. Signal VGATE3 may be generated by generator GE3 based on signals VGATE1 and VGATE 2. In some implementations, the signal generator GEN3 may include a NOR (NOR) gate. As shown in fig. 5, the nor gate may receive signals VGATE1 and VGATE2 as inputs and generate signal VGATE3 by performing a nor gate operation on signals VGATE1 and VGATE 2.

As shown in fig. 6A-B, one or more of the following may be selected: (i) the value (e.g., level) of voltage signal VREF, (ii) the value (e.g., level) of cutoff voltage Vc1 of signal generator GEN 1525, and (iii) the value (e.g., level) of cutoff voltage Vc2 of signal generator GEN 2526, such that only one of signals VGATE1 and VGATE2 is at a logic high level at any given time. This may be required so that at any given time, current from the current source 532 may be diverted to only one channel (e.g., only one of the light sources 512 and 516). In some implementations, it may be advantageous to transfer current from the current source 532 to only one channel at any given time, as it may allow for more precise control of the brightness of the

light sources

512 and 516.

In some implementations, as shown in fig. 6A-B, one of signals VGATE1 and VGATE2 may always have a duty cycle of 0% while the other may have a duty cycle greater than 0%. In such an instance, signal VGATE3 may be generated by a given one of inverted signals VGATE1 and VGATE2 having a larger duty cycle. As a result, the sum of the duty cycle of the signal VGATE3 and a given signal of the signals VGATE1 and VGATE2 having a larger duty cycle may be equal to 100%. Briefly, in the example of fig. 6A-B, signal VGATE3 is the inverse of one of signals VGATE1 and VGATE 2. According to aspects of the present disclosure, when a value of one PWM signal is inverted from a value of another PWM signal, the signal is an inversion of the other PWM signal. For example, as shown in fig. 6A, signal VGATE3 may be considered an inverse of signal VGATE1, because signal VGATE3 is always at logic high when signal VGATE1 is at logic low, and vice versa.

Briefly, in some implementations, the light engine 530 may direct current generated by the current source 532 to three PWM channels (e.g., PWR1, PWR2, PWR 3) whose duty cycles sum to 1. This effect can be achieved by: (i) ensure that only one of signals VGATE1 and VGATE2 is at a logic high value at any given time, (ii) ensure that signal VGATE3 is the inverse of the one of signals VGATE1 and VGATE2 that has the larger duty cycle. Diverting the current from the current source 532 in this manner may help achieve more precise control of the brightness of the light output from the light sources 512-516.

As described above, the operation of the light engine 530 may depend on the reference signal VREF, the cutoff voltage Vc of the signal generator GEN 1525₁And the cut-off voltage Vc of the signal generator GEN 2526₂And one or more of the magnitude of the R2/R1 ratio. The disclosure is not limited to the reference signal VREF, the cut-off voltage Vc of the signal generator GEN 1525₁And the cut-off voltage Vc of the signal generator GEN 2526₂And any specific value of the ratio R2/R1. The value of any of these variables may vary in different configurations of the illumination system 500And may be selected according to desired design specifications.

As described above, control signal VCTRL1 may be generated by control signal interface 520 in response to a user input indicating a desired CCT (and/or color) of light output by light fixture 510. Thus, control signal VCTRL1 may be a voltage signal indicative of a desired CCT (and/or color) of light emitted from light device 510.

The control signal VCTRL1 may determine when the light source 512 is to be turned off. More specifically, when the amplitude of the control signal VCTRL1 exceeds the cut-off voltage Vc of the signal generator GEN 1525₁At this time, the light source 512 may be turned off. The reference signal VREF may determine when the light source 516 is to be turned on. If the value of the reference signal VREF is lower than the cut-off voltage Vc of the signal generator GEN 1525₁Twice as many light sources 514 may be turned on before light sources 512 are turned off. Conversely, if the value of the reference signal VREF is higher than the cut-off voltage Vc of the signal generator GEN 1525₁Twice as many, then the light source 514 may be turned on before the light source 512 is turned off. Similarly, when the signal VREF equals to the cut-off voltage Vc of the signal generator GEN 1525₁Twice as many light sources 514 may be switched while light source 512 is off.

The ratio R2/R1 may determine the rate at which the brightness of the light source 514 changes in response to changes in the signal VCTRL 1. This in turn affects the responsiveness of the illumination system 500 to user input. As described above, in some implementations, the light source 514 may be a cool white light source and the control signal VCRL1 may be generated by the control signal interface 520 in response to a user turning a knob. In such an instance, when the ratio R2/R1 is high, the light output of the illumination system 500 will become cooler and more abrupt as the knob is turned. In contrast, when the R2/R1 ratio is low, the light output of the illumination system 500 may cool more slowly when the knob is actuated.

Fig. 7 shows a graph 700 illustrating the operation of the illumination system 500 according to one possible configuration of the light engine 530. In this configuration, the cut-off voltage Vc of the signal generator GEN 1525₁Cut-off voltage Vc of signal generator GEN 2526₂Same and the amplitude of the reference signal VREF is equal to the cut-off voltage Vc₁Twice as much. Plot 700 illustrates the relationship between the respective duty cycles of each of signals PWR1, PWR2, and PWR3 and control signal VCTRL 1. Further, the curve 700 shows that the lighting system 500 may have at least five operating states, enumerated here as states S0-S4.

When the control signal VCTRL1 is equal to 0V (VCTRL 1= 0V), the lighting system 500 may be in the state S0. When the illumination system 500 is in state S0, the light source 512 may be switched on (at maximum capacity) and the

light sources

514 and 516 may be switched off.

When the control signal VCTRL1 is greater than 0V and less than the cut-off voltage Vc of the signal generator GEN 1525₁（0<VCTRL1<Vc₁) The illumination system 500 may be in the S1 state. When the illumination system 500 is in the S1 state, the

light sources

512 and 516 may be turned on and the light source 514 may be turned off.

When the control signal VCTRL1 is equal to the cut-off voltage Vc of the signal generator GEN 1525₁（VCTRL1=Vc₁) The illumination system 500 may be in the S2 state. When the illumination system 500 is in the S2 state, the light source 516 may be on (at maximum capacity) and the

light sources

512 and 514 may be off.

When the control signal VCTRL1 is greater than the cut-off voltage Vc of the signal generator GEN 1525₁And is less than the reference signal VREF (Vc)₁<VCTRL1<VREF), the lighting system 500 may be in the S3 state. When the illumination system 500 is in the S3 state, the

light sources

514 and 516 may be turned on and the light source 512 may be turned off.

When the control signal VCTRL1 is greater than or equal to VREF (VCTRL 1 ≧ VREF), the lighting system 500 may be in the S4 state. When the illumination system 500 is in the S4 state, the light source 514 may be on (at maximum capacity) and the

light sources

512 and 516 may be off.

Fig. 8 shows a graph 800 illustrating the operation of the illumination system 500 according to another possible configuration of the light engine 530. In this configuration, the cut-off voltage Vc of the signal generator GEN 1525₁Cut-off voltage Vc of signal generator GEN 2526₂Same and the amplitude of the reference signal VREF is greater than the cut-off voltage Vc₁Twice the amplitude of (c). Curve 800 showsThe relationship between the respective duty cycles of each of the signals PWR1, PWR2, and PWR3 and the control signal VCTRL1 is shown. Further, the curve 800 shows that the lighting system 500 may have at least five operating states, enumerated here as states S0-S4.

When the control signal VCTRL1 is equal to 0V (VCTRL 1= 0V), the illumination system 500 may be in the state s 0. When the illumination system 500 is in state s0, the light source 512 may be switched on (at maximum capacity) and the

light sources

514 and 516 may be switched off.

light sources

512 and 516 may be turned on and the light source 514 may be turned off.

When the control signal VCTRL1 is greater than or equal to the cut-off voltage Vc of the signal generator GEN 1525₁And is less than or equal to Vm (Vc)₁VCTRL1 ≦ Vm), the lighting system 500 may be in the S2 state. When the illumination system 500 is in the S2 state, the light source 516 may be on (at maximum capacity) and the

light sources

512 and 514 may be off. In some implementations, the value Vm may be defined by equation 3 below:

equation 3

When the control signal VCTRL1 is greater than Vm and less than the reference signal VREF (Vm < VCTRL1< VREF), the illumination system 500 may be in the S3 state. When the illumination system 500 is in the S3 state, the

light sources

514 and 516 may be turned on and the light source 512 may be turned off. Thus, Vm may be the value of the control signal VCTRL1 when the light source 514 is on.

When the control signal VCTRL1 is greater than or equal to the reference signal VREF (VCTRL 1 ≧ VREF), the lighting system 500 may be in the S4 state. When the illumination system 500 is in the S4 state, the light source 514 may be on (at maximum capacity) and the

light sources

512 and 516 may be off.

Fig. 9 shows a graph 900 illustrating a configuration according to the illumination system 500 discussed with reference to fig. 8The relationship between the control signals VCTRL1 and VCTRL 2. As shown, when the control signal VCTRL1 reaches the cut-off voltage Vc of the signal generator GEN 1525₁At values of (3), light source 512 may be turned off and light source 516 may reach 100% brightness. When the control signal VCTRL1 exceeds the value Vm, the brightness of the light source 516 may begin to decrease. In addition, for the case of Vc₁And Vm, light source 516 may be operated at maximum brightness, and

light sources

512 and 514 may be turned off.

Curves

700 and 800 illustrate that the illumination system 500 may allow a user to change the color and/or CCT of the light output produced by the illumination system 500 without affecting the overall brightness of the light emitted from the illumination system 500. This concept is illustrated in

graphs

700 and 800. As illustrated by

curves

700 and 800, the lines representing signals PWR1 and PWR2 may have slopes that are equal in magnitude but opposite in sign to the slope of the line representing signal PWR 3. This means that any decrease in brightness of one of the

light sources

512 and 514 can be matched by an equal increase in brightness of the light source 516, and vice versa. Thus, in some implementations, when the CCT (or color) of the light output of the illumination system 500 changes (as a result of the change in the control signal VCTRL 1), the change may occur without any increase or decrease in the brightness of the light output of the illumination system 500.

FIG. 10 is a flow diagram of an example of a process according to aspects of the present disclosure. In some implementations, all steps in process 1000 may be performed simultaneously based on the sequence of reference numbers provided in fig. 10. Alternatively, in some implementations, some or all of the steps in process 1000 may be performed sequentially, e.g., as outlined by the flow arrows provided in fig. 10. Process 1000 may be performed by lighting system 100, illumination system 500, and/or any other suitable type of electronic device. For example, in some implementations, at least some of the steps in process 1000 may be performed using processing circuitry, such as a microprocessor { e.g., an ARM-based processor, an Arduino-based processor, etc.). Additionally or alternatively, in some implementations, at least some of the steps in process 1000 may be performed using electronic circuitry, such as the electronic circuitry shown in fig. 5.

At step 1010, a first control signal is received, the first control signal indicating a desired CCT and/or a desired color of light output. The control signal may be received from a control signal interface, such as

control signal interface

110 or 520. In some implementations, the control signal may be a voltage signal, such as control signal VCTRL 1. In some implementations, the control signal may be a digital representation of a number or alphanumeric string that indicates the desired CCT and/or color. At step 1020, a reference signal is generated. In some implementations, the reference signal may be a voltage signal, such as signal VREF. Additionally or alternatively, in some implementations, the reference signal may be a digital representation of a number and/or alphanumeric string. At step 1030, a second control signal is generated based on at least one of the reference signal and the first control signal. In some implementations, the second control signal may be generated by subtracting the first control signal from the reference signal.

At step 1040, a first PWM signal is generated based on the first control signal. In some implementations, the first PWM signal may have a duty cycle based on the first control signal. In some implementations, the duty cycle of the first PWM signal may be proportional to the amplitude of the first control signal (e.g., proportional to the level of the first control signal).

At step 1050, a second PWM signal is generated. In some implementations, the duty cycle of the second PWM signal may be generated based on at least one of the first control signal and the reference signal. Additionally or alternatively, in some implementations, the second control signal may be generated based on the second control signal. Additionally or alternatively, in some implementations, the second PWM signal may have a duty cycle that is proportional to the magnitude of the second control signal.

At step 1060, a third PWM signal is generated based on at least one of the first PWM signal and the second PWM signal. In some implementations, the third PWM signal may have a different duty cycle than the first and second PWM signals. In some implementations, the third PWM signal may be generated by inverting one of the first and second PWM signals having a larger duty cycle. Additionally or alternatively, in some implementations, the third PWM signal may be generated by performing a NOR (NOR) operation on the first and second PWM signals.

In step 1070, the first light source is controlled based on the first PWM signal. The first light source may comprise one or more LEDs and/or any other suitable type of light source. In some implementations, controlling the first light source may include turning the first light source on and/or off based on the first PWM signal. Additionally or alternatively, in some implementations, controlling the first light source may include increasing and/or decreasing a brightness of the first light source. Additionally or alternatively, in some implementations, controlling the first light source may include changing a state of a switch that controls a current on the first light source based on the first PWM signal.

At step 1080, the second light source is controlled based on the second PWM signal. The second light source may comprise one or more LEDs and/or any other suitable type of light source. In some implementations, controlling the second light source may include turning the second light source on and/or off based on the second PWM signal. Additionally or alternatively, in some implementations, controlling the second light source may include increasing and/or decreasing a brightness of the second light source. Additionally or alternatively, in some implementations, controlling the second light source may include changing a state of a switch that controls current on the second light source based on the second PWM signal.

At step 1090, a third light source is controlled based on the third PWM signal. The third light source may comprise one or more LEDs and/or any other suitable type of light source. In some implementations, controlling the third light source may include turning the third light source on and/or off based on the third PWM signal. Additionally or alternatively, in some implementations, controlling the third light source may include increasing and/or decreasing a brightness of the third light source. Additionally or alternatively, in some implementations, controlling the third light source may include changing a state of a switch that controls current on the third light source based on the third PWM signal.

Fig. 1-10 are provided as examples only. Although in the example of fig. 5, switches SW1 and SW2 are implemented as MOSFET transistors, any suitable type of switch may alternatively be used, such as solid state relays, PMOS transistors, and the like. Although in the example of fig. 5 the subtractor SUB1 is implemented using an operational amplifier, any suitable type of electronic circuit may be used instead to implement the subtractor. Although in the example of fig. 3, generator GEN3 is implemented using a nor gate, any other suitable type of circuit may be used instead. For example, the signal generator GEN3 may be implemented by using an OR gate and one OR more inverters, etc. At least some of the elements discussed with respect to these figures may be arranged in a different order, combined, and/or omitted entirely.

Fig. 11 is a top view of an electronic board 310 of an integrated LED lighting system according to an embodiment. In alternative embodiments, two or more electronic boards may be used for the LED lighting system. For example, the LED array may be on a separate electronic board, or the sensor module may be on a separate electronic board. In the example shown, the electronic board 310 includes a power module 312, a sensor module 314, a connection and control module 316, and an LED attachment area 318 reserved for attaching an LED array to a substrate 320. The power module 312 of fig. 11 may include a light engine (e.g., light engine 530 of fig. 5) as disclosed herein.

Substrate 320 may be any board capable of mechanically supporting and providing electrical coupling to electrical components, electronic components, and/or electronic modules using electrically conductive connectors, such as traces, pads, vias, and/or wires. The substrate 320 may include one or more metallization layers disposed between or over one or more layers of non-conductive material, such as a dielectric composite material. The power module 312 may include electrical and/or electronic components. In an example embodiment, the power module 312 includes an AC/DC conversion circuit, a DC/DC conversion circuit, a dimming circuit, and an LED driver circuit.

The sensor module 314 may include sensors as needed to implement the application of the LED array. Example sensors may include optical sensors (e.g., IR sensors and image sensors), motion sensors, thermal sensors, mechanical sensors, proximity sensors, or even timers. For example, LEDs in street lighting, general lighting, and horticulture lighting applications may be turned off/on and/or adjusted based on a number of different sensor inputs, such as detecting the presence of a user, detected ambient lighting conditions, detected weather conditions, or based on time of day/night. This may include, for example, adjusting the intensity of the light output, the shape of the light output, the color of the light output, and/or turning the light on or off to conserve energy. For AR/VR applications, a motion sensor may be used to detect user motion. The motion sensor itself may be an LED, such as an IR detector LED. As another example, for camera flash applications, images and/or other optical sensors or pixels may be used to measure the illumination of a scene to be captured, such that the flash illumination color, intensity illumination pattern, and/or shape may be optimally calibrated. In an alternative embodiment, the electronics board 310 does not include a sensor module.

The connection and control module 316 may include a system microcontroller and any type of wired or wireless module configured to receive control inputs from external devices. For example, the wireless module may include bluetooth, Zigbee, Z-wave, mesh network, Wi-Fi, Near Field Communication (NFC), and/or peer-to-peer modules. The microcontroller may be any type of special purpose computer or processor that may be embedded in the LED lighting system and configured or configurable to receive input (such as sensor data and data fed back from the LED modules) from wired or wireless modules or other modules in the LED system and provide control signals to the other modules based thereon. The control signal interface 110 disclosed herein may be part of a microcontroller, or may receive an input or provide an output to a microcontroller. The algorithms implemented by the special purpose processor may be implemented in a computer program, software, or firmware embodied in a non-transitory computer readable storage medium for execution by the special purpose processor. Examples of non-transitory computer readable storage media (ROM) include Read Only Memory (ROM), Random Access Memory (RAM), registers, cache memory, and semiconductor memory devices. The memory may be included as part of the microcontroller, or may be implemented elsewhere, either on the electronic board 310 or external to the electronic board 310.

The term "module" as used herein may refer to electrical and/or electronic components disposed on various circuit boards, which may be soldered to one or more electronic boards 310. However, the term module may also refer to electrical and/or electronic components that provide similar functionality, but which may be individually soldered to one or more circuit boards in the same area or in different areas.

Fig. 12a is a top view of the electronic circuit board 310 with the LED array 410 attached to the substrate 320 at the LED device attachment area 318, in one embodiment. The electronic board 310 together with the LED array 410 represents the LED lighting system 400A. In addition, the power module 312 receives the voltage input at Vin 497 and the control signal from the connection and control module 316 through trace 418B and provides the drive signal to the LED array 410 through trace 418A. The LED array 410 is turned on and off by a driving signal from the power module 312. In the embodiment shown in FIG. 12, the connection and control module 316 receives sensor signals from the sensor module 314 via trace 418. The power module 312 of fig. 12 may include a light engine disclosed herein (e.g., light engine 530 of fig. 5) and may provide PWM signals disclosed herein to the LEDs in the LED array 410.

Figure 12b illustrates one embodiment of a dual channel integrated LED lighting system with electronic components mounted on both surfaces of circuit board 499. As shown in fig. 12B, the LED lighting system 400B includes a first surface 445A and an AC/DC converter circuit 412 mounted thereon, the first surface 445A having inputs to receive a dimming signal and an AC power signal. The LED system 400B includes a second surface 445B, DC-

DC converter circuits

440A and 440B having a dimmer interface circuit 415, a connection and control module 416 (a wireless module in this example) having a microcontroller 472, and an LED array 410 mounted thereon. The LED array 410 is driven by two independent channels 411A and 411B. In alternative embodiments, a single channel may be used to provide a drive signal to the LED array, or any number of multiple channels may be used to provide a drive signal to the LED array. For example, fig. 12E shows an LED illumination system 400D having 3 channels (e.g.,

channels

522, 523, and 524 of fig. 5 as disclosed herein) and will be described in further detail below.

The LED array 410 may include two or more sets of LED devices. In an example embodiment, the LED devices of group A are electrically coupled to a first channel 411A and the LED devices of group B are electrically coupled to a second channel 411B. Each of the two DC-

DC converters

440A and 440B may provide a respective drive current via a single channel 411A and 411B, respectively, for driving a respective LED group a and B in the LED array 410. The LEDs of one set of LEDs may be configured to emit light having a different color point than the LEDs of the second set of LEDs. By controlling the current and/or duty cycle applied by the respective DC/

DC converter circuits

440A and 440B via the single channels 411A and 411B, respectively, the control of the composite color point of the light emitted by the LED array 410 can be adjusted within a range. Although the embodiment shown in fig. 12B does not include a sensor module (as described in fig. 11 and 12), alternative embodiments may include a sensor module.

The illustrated LED lighting system 400B is an integrated system in which the LED array 410 and circuitry for operating the LED array 410 are disposed on a single electronic board. Connections between modules on the same surface of circuit board 499 may be electrically coupled to exchange, for example, voltage, current, and control signals between modules through surface or sub-surface interconnections, such as

traces

431, 432, 433, 434, and 435 or metallization layers (not shown). Connections between modules on opposite surfaces of circuit board 499 may be electrically coupled by through-board interconnects such as vias and metallization layers (not shown).

Fig. 12c shows an embodiment of the LED lighting system where the LED array is located on an electronic board separate from the driver and control circuitry. LED lighting system 400C includes a power module 452 on a different electronic board than LED module 490. The power module 452 may include the AC/DC converter circuit 412, the sensor module 414, the connection and control module 416, the dimmer interface circuit 415, and the DC/DC converter 440 on the first electronic board. The LED module 490 may include embedded LED calibration and setting data 493, as well as the LED array 410, on a second electronic board. Data, control signals, and/or LED driver input signals 485 may be exchanged between the power module 452 and the LED module 490 via wires, which may be electrically and communicatively coupled to both modules. Embedded LED calibration and setting data 493 may include any data needed by other modules within a given LED lighting system to control how the LEDs in the LED array are driven. In one embodiment, the embedded calibration and setting data 493 may include data required by the microcontroller to generate or modify a control signal instructing the driver to power each LED group a and B using, for example, a Pulse Width Modulation (PWM) signal. In this example, the calibration and setting data 493 may inform the microcontroller 472, for example, of the number of power channels to be used, the desired color point of the composite light to be provided by the entire LED array 410, and/or the percentage of power to be provided to each channel by the AC/DC converter circuit 412.

Fig. 12d shows a block diagram of an LED lighting system with an array of LEDs and some of the electronics on the electronics board separate from the driver circuit. LED system 400D includes a power conversion module 483 and an LED module 481 on separate electronic boards. The power conversion module 483 can include the AC/DC converter circuit 412, the dimmer interface circuit 415, and the DC-DC converter circuit 440, and the LED module 481 can include embedded LED calibration and setting data 493, the LED array 410, the sensor module 414, and the connection and control module 416. The power conversion module 483 can provide the LED driver input signal 485 to the LED array 410 via a wired connection between the two electronic boards.

Fig. 12e is a diagram illustrating an example LED lighting system 400D of a multi-channel LED driver circuit. In the illustrated example, the system 400D includes a power module 452 and an LED module 491, the LED module 491 including embedded LED calibration and setting data 493 and three sets of

LEDs

494A, 494B, and 494C. As disclosed herein, the power module 452 may include a light engine 530 such that the power module 542 may receive a control signal via a control channel and may generate three PWM signals to power an LED group containing one or more LEDs. Although three sets of LEDs are shown in fig. 12e, one of ordinary skill in the art will recognize that any number of sets of LEDs may be used consistent with the embodiments described herein. Further, while the individual LEDs in each group are arranged in series, they may be arranged in parallel in some embodiments.

The LED array 491 may include groups of LEDs that provide light having different color points. For example, the LED array 491 may include a warm white light source via the first set of LEDs 494A, a cool white light source via the second set of LEDs 494B, and a neutral white light source via the third set of LEDs 494C. The warm white light source via the first set of LEDs 494A may include one or more LEDs configured to provide white light having a Correlated Color Temperature (CCT) of about 2700K. The cool white light source via the second set of LEDs 494B may include one or more LEDs configured to provide white light having a CCT of about 6500K. The neutral white light source via the third set of LEDs 494C may include one or more LEDs configured to provide light having a CCT of about 4000K. Although various white LEDs are described in this example, one of ordinary skill in the art will recognize that other color combinations consistent with the embodiments described herein are possible to provide composite light output of the LED array 491 having various overall colors.

The power module 452 may include a dimmable engine (not shown) that may be configured to power the LED array 491 through three separate channels (represented in fig. 12e as LED1+, LED2+, and LED3 +). More specifically, the dimmable engine may be configured to provide a first PWM signal to a first set of LEDs 494A (such as a warm white light source) via a first channel, a second PWM signal to a second set of LEDs 494B via a second channel, and a third PWM signal to a third set of LEDs 494C via a third channel. Each signal provided via a respective channel may be used to power a respective LED or group of LEDs, and the duty cycle of the signal may determine the total duration of the on and off states of each respective LED. The duration of the on and off states may result in an overall light effect, which may have light properties (e.g. Correlated Color Temperature (CCT), color point or brightness) based on the duration. In operation, the dimmable engine may vary the relative magnitudes of the duty cycles of the first, second, and third signals to adjust the respective light properties of each group of LEDs to provide composite light having the desired emission from the LED array 491. As described above, the light output of the LED array 491 can have a color point that is based on a combination (e.g., a mixture) of the light emissions from each set of

LEDs

494A, 494B, and 494C.

In operation, the power module 452 may receive control inputs generated based on user and/or sensor inputs and provide signals via the various channels to control the composite color of light output by the LED array 491 based on the control inputs. In some embodiments, a user may provide input to the LED system for controlling the DC/DC converter circuit by turning a knob or moving a slider, which may be part of a sensor module (not shown), for example. Additionally or alternatively, in some embodiments, a user may provide input to the LED lighting system 400 using a smartphone and/or other electronic device to send an indication of a desired color to a wireless module (not shown).

Fig. 13 shows an example system 950 that includes an application platform 960, LED lighting systems 952 and 956, and

secondary optics

954 and 958. LED lighting system 952 generates a light beam 961 shown between arrows 961a and 961 b. The LED illumination system 956 may produce a light beam 962 between

arrows

962a and 962 b. In the embodiment shown in fig. 13, light emitted from the LED illumination system 952 passes through the secondary optic 954 and light emitted from the LED illumination system 956 passes through the secondary optic 958. In an alternative embodiment,

light beams

961 and 962 do not pass through any secondary optics. The secondary optic may be or may include one or more light guides. One or more of the light guides may be edge-lit or may have an interior opening defining an interior edge of the light guide. The LED illumination systems 952 and/or 956 may be inserted into the inner openings of the one or more light guides such that they inject light into the inner edges (inner opening light guides) or the outer edges (edge-lit light guides) of the one or more light guides. The LEDs in the LED lighting system 952 and/or 956 may be arranged around the circumference of the base as part of the light guide. According to one implementation, the base may be thermally conductive. According to one implementation, the base may be coupled to a heat dissipation element disposed on the light guide. The heat dissipating element may be arranged to receive heat generated by the LED via the thermally conductive substrate and dissipate the received heat. The one or more light guides may allow the light emitted by the LED illumination systems 952 and 956 to be shaped in a desired manner, e.g., with a gradient, a chamfered distribution, a narrow distribution, a wide distribution, an angular distribution, etc.

In an example embodiment, the system 950 may be a mobile phone with a camera flash system, indoor residential or commercial lighting, outdoor lighting such as street lighting, automobiles, medical devices, AR/VR devices, and robotic devices. The integrated LED lighting system 400A shown in fig. 12, the integrated LED lighting system 400B shown in fig. 12B, the LED lighting system 400C shown in fig. 12C, and the LED lighting system 400D shown in fig. 12D illustrate the LED lighting systems 952 and 956 in example embodiments.

In an example embodiment, the system 950 may be a mobile phone of a camera flash system, indoor residential or commercial lighting, outdoor lighting such as street lighting, automobiles, medical devices, AR/VR devices, and robotic devices. The integrated LED lighting system 400A shown in fig. 12, the integrated LED lighting system 400B shown in fig. 12B, the LED lighting system 400C shown in fig. 12C, and the LED lighting system 400D shown in fig. 12D illustrate the LED lighting systems 952 and 956 in example embodiments.

Application platform 960 may provide power to LED lighting systems 952 and/or 956 via a power bus of line 965 or other suitable input, as described herein. Further, application platform 960 may provide input signals via lines 965 for operation of LED lighting system 952 and LED lighting system 956, which may be based on user input/preferences, sensed readings, preprogrammed or autonomously determined outputs, and the like. The one or more sensors may be internal or external to the housing of the application platform 960.

In various embodiments, the application platform 960 sensor and/or the LED lighting system 952 and/or 956 sensors may collect data, such as visual data (e.g., LIDAR data, IR data, data collected by a camera, etc.), audio data, distance-based data, motion data, environmental data, and the like, or combinations thereof. The data may be related to a physical item or entity, such as an object, a person, a vehicle, etc. For example, the sensing device may collect object proximity data for an ADAS/AV based application, which may prioritize detection and follow-up actions based on detection of a physical item or entity. Data may be collected based on, for example, optical signals (such as infrared signals) emitted by LED lighting systems 952 and/or 956, and data collected based on the emitted optical signals. Data may be collected by a component other than the component that emits the optical signal used for data collection. Continuing with this example, the sensing device may be located on an automobile and may emit a light beam using a Vertical Cavity Surface Emitting Laser (VCSEL). One or more sensors may sense a response to the emitted light beam or any other suitable input.

In an example embodiment, the application platform 960 may represent an automobile, and the LED lighting system 952 and LED lighting system 956 may represent automobile headlamps. In various embodiments, system 950 may represent an automobile with a controllable light beam, where LEDs may be selectively activated to provide controllable light. For example, an array of LEDs may be used to define or project a shape or pattern, or to illuminate only selected portions of a roadway. In an exemplary embodiment, the infrared camera or detector pixels within the LED lighting systems 952 and/or 956 may be sensors that identify portions of the scene (roads, crosswalks, etc.) that require illumination.

Fig. 14A is a diagram of the LED device 201 in an example embodiment. The LED device 201 may include a substrate 202, an active layer 204, a wavelength converting layer 206, and a primary optic 208. In other embodiments, the LED device may not include a wavelength converter layer and/or primary optics. The individual LED devices 201 may be included in an LED array in an LED lighting system, such as any of the LED lighting systems described above.

As shown in fig. 14A, the active layer 204 may be adjacent to the substrate 202 and emit light when energized. Suitable materials for forming the substrate 202 and the active layer 204 include sapphire, SiC, GaN, siloxane, and more particularly, may be formed of group III-V semiconductors including, but not limited to, AIN, AIP, AIAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, formed of group II-VI semiconductors including, but not limited to, ZnS, ZnSe, CdTe, formed of group IV semiconductors including, but not limited to, Ge, Si, SiC, and mixtures or alloys thereof.

Wavelength-converting layer 206 may be located remotely, proximate to, or directly above active layer 204. Active layer 204 emits light into wavelength-converting layer 206. Wavelength-converting layer 206 is used to further modify the wavelength of light emitted by active layer 204. LED devices that include a wavelength conversion layer are commonly referred to as phosphor converted LEDs ("PCLEDs"). The wavelength conversion layer 206 may comprise any luminescent material, such as phosphor particles in a transparent or translucent binder or matrix, or ceramic phosphor elements that absorb light of one wavelength and emit light of a different wavelength.

The primary optic 208 may be on one or more layers of the LED device 201 and allow light from the active layer 204 and/or the wavelength conversion layer 206 to pass through the primary optic 208. The primary optic 208 may be a lens or package configured to protect one or more layers and at least partially shape the output of the LED device 201. The primary optic 208 may comprise a transparent and/or translucent material. In an example embodiment, light via the primary optic may be emitted based on a lambertian distribution pattern. It should be appreciated that one or more properties of the primary optic 208 may be modified to produce a light distribution pattern that is different from a lambertian distribution pattern.

Fig. 14B shows a cross-sectional view of the illumination system 221 in an example embodiment, the illumination system 221 comprising an LED array 211 with

pixels

201A, 201B and 201C and a secondary optic 212. The LED array 211 includes

pixels

201A, 201B, and 201C, each including a respective wavelength converting layer 206B, active layer 204B, and substrate 202B. The LED array 211 may be a monolithic LED array fabricated using wafer-level processing techniques, a micro LED having a sub-500 micron size, or the like. The

pixels

201A, 201B, and 201C in the LED array 211 may be formed using array segmentation or alternatively using pick and place techniques.

The space 203 shown between one or

more pixels

201A, 201B, and 201C of the LED device 200B may include an air gap or may be filled with a material, such as a metallic material, which may be a contact (e.g., an n-contact).

Secondary optic 212 may include one or both of lens 209 and waveguide 207. It should be appreciated that although secondary optics are discussed in accordance with the illustrated example, in an example embodiment, secondary optics 212 may be used to expand incident light (diverging optics) or to concentrate incident light into a collimated beam (collimating optics). In an example embodiment, the waveguide 207 may be a light concentrator, and may have any suitable shape to concentrate light, such as a parabolic shape, a conical shape, a sloped shape, and the like. Waveguide 207 may be coated with a dielectric material, a metallization layer, or the like for reflecting or redirecting incident light. In alternative embodiments, the lighting system may not include one or more of the following: conversion layer 206B, primary optic 208B, waveguide 207, and lens 209.

The lens 209 may be formed of any suitable transparent material, such as, but not limited to, SiC, alumina, diamond, and the like, or combinations thereof. The lens 209 may be used to modify the light beam input into the lens 209 so that the output beam from the lens 209 will effectively meet the desired photometric specifications. Additionally, the lens 209 may serve one or more aesthetic purposes, such as by determining the illuminated and/or non-illuminated appearance of the

pixels

201A, 201B, and/or 201C of the LED array 211.

Having described embodiments in detail, those skilled in the art will appreciate that given the present description, modifications may be made to the embodiments described herein without departing from the spirit of the inventive concept. Therefore, it is intended that the scope of the invention not be limited to the particular embodiments illustrated and described.

Claims

1. A system, comprising:

a control signal interface configured to provide a voltage control signal via a control channel; and

a light engine, comprising:

a first signal generator configured to provide a first Pulse Width Modulation (PWM) signal based on the control signal via a first channel;

a second signal generator configured to provide a second PWM signal based on the control signal via a second channel; and

a third signal generator configured to provide a third PWM signal based on the first PWM signal and the second PWM signal via a third channel.

2. The system of claim 1, further comprising:

an optical device, comprising:

a first Light Emitting Diode (LED) electrically coupled to receive the first PWM signal provided via the first channel and configured to emit light having a first property;

a second LED powered using the first PWM signal provided via the second channel and configured to emit light having a second attribute; and

a third LED powered using the first PWM signal provided via the third channel and configured to emit light having a third property.

3. The system of claim 1, wherein the voltage control signal is provided based on a user input received at the control signal interface.

4. The system of claim 2, wherein the first LED is configured to emit warm white light, the second LED is configured to emit cool white light, and the third LED is configured to emit neutral white light.

5. The system of claim 2, wherein the first LED is configured to emit red light, the second LED is configured to emit blue light, and the third LED is configured to emit green light.

6. The system of claim 1, wherein:

the first control signal is a voltage signal having a first amplitude,

the first signal generator is configured to turn off the first LED when the first control signal exceeds a cutoff voltage of the first signal generator, and

the reference signal is a voltage signal having a second magnitude greater than or equal to the cutoff voltage of the first signal generator such that the second PWM signal is further based on the reference signal.

7. The system of claim 1, wherein the third signal generator comprises a nor gate arranged to receive the first and second PWM signals as inputs.

8. The system of claim 1, further comprising:

a first switch configured to control current through the first LED based on the first PWM signal;

a second switch configured to control current through the second LED based on the second PWM signal; and

a third switch configured to control current through the third LED based on the third PWM signal.

9. An apparatus, comprising:

a first signal generator configured to provide a first PWM signal based on a control signal;

a second signal generator configured to provide a second PWM signal based on the first PWM signal; and

a third signal generator configured to provide a third PWM signal based on the first PWM signal and the second PWM signal.

10. The apparatus of claim 9, further comprising:

a first Light Emitting Diode (LED) powered using the first PWM, the first LED configured to emit light having a first attribute;

a second LED powered using the second PWM signal, the second LED configured to emit light having a second attribute; and

a third LED powered using the third PWM signal, the third LED configured to emit light having a third property.

11. The device of claim 10, wherein the first LED is configured to emit warm white light, the second LED is configured to emit cool white light, and the third LED is configured to emit neutral white light.

12. The device of claim 10, wherein the first LED is configured to emit red light, the second LED is configured to emit blue light, and the third LED is configured to emit green light.

13. The apparatus of claim 9, wherein:

the first control signal is a voltage signal having a first amplitude,

14. The apparatus of claim 9, wherein the third signal generator comprises a nor gate arranged to receive the first and second PWM signals as inputs.

15. The apparatus of claim 9, further comprising:

16. A method, comprising:

receiving a voltage control signal via a control channel;

providing, via a first channel, a first PWM signal based on the voltage control signal;

providing a second PWM signal based on a reference signal and the voltage control signal via a second channel;

providing, via a third channel, a third PWM signal based on the first PWM signal and the second PWM signal, the third PWM signal having a different duty cycle than at least one of the first PWM signal and the second PWM signal;

controlling a first LED based on the first PWM signal provided via the first channel, the first LED configured to output light having a first attribute;

controlling a second LED based on the second PWM signal provided via the second channel, the second LED configured to output light having a second attribute; and

controlling a third LED based on the third PWM signal provided via the third channel, the third LED configured to output light having a third attribute.

17. The method of claim 16, wherein the first LED is configured to emit warm white light, the second LED is configured to emit cool white light, and the third LED is configured to emit neutral white light.

18. The method of claim 16, wherein the first LED is configured to emit red light, the second LED is configured to emit blue light, and the third LED is configured to emit green light.

19. The method of claim 16, wherein the first control is generated based on user input received at a control signal interface.

20. The method of claim 16, wherein:

generating the third PWM signal by inverting the first PWM signal when the first PWM signal has a duty ratio greater than that of the second PWM signal, and generating the third PWM signal by inverting the second PWM signal if the second PWM signal has a duty ratio greater than that of the first PWM signal.