Patent Publication Number: US-2016227616-A1

Title: Led driving device and led lighting device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119 to Korean Patent Application No. 10-2015-0017204, filed on Feb. 4, 2015, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
     TECHNICAL FIELD 
     The present inventive concept relates to a Light Emitting Diode (LED) driving device and to an LED lighting device. 
     DISCUSSION OF THE RELATED ART 
     Light Emitting Diodes (LEDs) feature low power consumption, high levels of luminance, and durability. Thus, the use of LEDs as general light sources is increasingly expanding in a number of areas such as lighting equipment, automotive lighting, and backlight units of display devices. Accordingly, research in driving devices that efficiently drive LEDs is being undertaken. 
     An automotive headlamp may include a plurality of light sources operating independently of each other depending on their respective purposes. For example, the plurality of light sources of an automobile may include low beam lights, high beam lights, daytime running lights (DRL), turn signal lights and the like. When using LEDs in automotive headlamps, more than one LED may be included in each of the plurality of light sources having different purposes with respect to each other, and a driving device for driving the plurality of light sources independently of one another may be required. As a result, circuit complexity and manufacturing costs thereof may increase due to each of the plurality of light sources being provided with a circuit supplying driving power to the plurality of light sources and due to providing a circuit for controlling the driving power of the plurality of light sources. Further, the hardware design of the driving devices may need to be modified to meet the requirements of the specific guidelines applicable to automotive lighting. 
     SUMMARY 
     According to an exemplary embodiment of the present inventive concept, a light emitting diode (LED) driving device includes a power supply module configured to supply driving power to a light source, wherein the light source includes a plurality of LED elements, an information acquisition module configured to acquire operating data of the power supply module and characteristic data of the plurality of LED elements, and a control module configured to control an operation of the power supply module based on the operating data and the characteristic data. The information acquisition module and the control module are included in a programmable microcontroller unit (MCU), and the MCU executes stored codes to provide control signals to the control module to operate the power supply module. 
     In an exemplary embodiment of the present inventive concept, the information acquisition module includes a monitoring unit configured to detect an input voltage, an input current, an output voltage, or an output current of the power supply module. A bin information detector is configured to detect bin data related to the plurality of LED elements, a temperature detector is configured to detect a temperature of the plurality of LED elements, and a memory unit is configured to store the characteristic data of the plurality of LED elements. 
     In an exemplary embodiment of the present inventive concept, the characteristic data of the plurality of LED elements includes at least one of current-voltage characteristic data, current-output characteristic data, and junction temperature-output characteristic data, and the memory unit comprises a lookup table including the current-voltage characteristic data, the current-output characteristic data, or the junction temperature-output characteristic data of the plurality of LED elements. 
     In an exemplary embodiment of the present inventive concept, the control module selects at least one of the characteristic data included in the lookup table based on the bin data detected by the bin information detector, and controls the operation of the power supply module by applying the data detected by the monitoring unit and the temperature detector to the selected characteristic data. 
     In an exemplary embodiment of the present inventive concept, the control module includes a protection module configured to determine whether to block input power supplied to the power supply module based on the operating data, and an output control module is configured to control a voltage and a current being output by the power supply module based on the operating data or the characteristic data. 
     In an exemplary embodiment of the present inventive concept, the output control module comprises a Direct Current to Direct Current (DC/DC) controller configured to control a duty ratio of switching elements included in the power supply module, and a linear controller configured to control an output of the power supply module linearly. 
     In an exemplary embodiment of the present inventive concept, an LED driving device further includes a communications module included in the MCU, wherein the communications module is connected to an external controller to communicate with the external controller. 
     In an exemplary embodiment of the present inventive concept, the external controller is a body control module (BCM) of a vehicle. 
     In an exemplary embodiment of the present inventive concept, the plurality of LED elements are arranged in a plurality of LED arrays that operate independently of each other, wherein a first array of the plurality of LED arrays is operated by a first driving voltage that is different from a second driving voltage that operates a second array of the plurality of LED arrays, and wherein the first array of the plurality of LED arrays is operated by a first driving current that is different from a second driving current that operates the second array of the plurality of LED arrays. 
     In an exemplary embodiment of the present inventive concept, the control module controls the operation of the power supply module when at least one LED array of the plurality of LED arrays is selected to operate based on a driving voltage and a driving current required to operate the selected LED array. 
     In an exemplary embodiment of the present inventive concept, the MCU includes the power supply module, the information acquisition module, and the control module. 
     According to an exemplary embodiment of the present inventive concept, an LED lighting device includes a light source including a plurality of LED arrays, a power supply module configured to generate driving power to operate the plurality of LED arrays, and a control module included in an MCU and configured to operate the power supply module based on characteristic data of the plurality of LED arrays and operating data related to the power supply module. The control module includes a stored program executed by the MCU. 
     In an exemplary embodiment of the present inventive concept, the light source is included in an automotive headlamp, and the plurality of LED arrays provides illumination for low beam lights, high beam lights, daytime running lights (DRL), or turn signal lights of the automotive headlamp. 
     In an exemplary embodiment of the present inventive concept, the operating data related to the power supply module includes an input voltage, an input current, an output voltage, or an output current of the power supply module, and the characteristic data related to the plurality of LED elements includes bin data, temperature data, current-voltage characteristic data, current-output characteristic data, and junction temperature-output characteristic data related to the plurality of LED elements. 
     In an exemplary embodiment of the present inventive concept, the characteristic data related to the plurality of LED elements includes current-voltage characteristic data, current-output characteristic data, and junction temperature-output characteristic data, wherein the control module controls the operation of the power supply module using the current-voltage characteristic data, the current-output characteristic data, and the junction temperature-output characteristic data related to the plurality of LED elements, wherein the current-voltage characteristic data, the current-output characteristic data, and the junction temperature-output characteristic data related to the plurality of LED elements are stored in a lookup table. 
     According to an exemplary embodiment of the present inventive concept, an LED lighting device includes a light source module including a plurality of LEDs, and a power supply module driving the plurality of LEDs. The light source module includes a controller configured to control an operation of the power supply module using a stored program executed by an MCU. The controller controls the operation of the power supply module using characteristic data of the plurality of LEDs and operating data of the power supply module. The plurality of LEDs is arranged into a plurality of LED strings, each LED string of the plurality of LED strings being independently driven by the power supply module. 
     In an exemplary embodiment of the present inventive concept, the operating data of the power supply module includes an input voltage, an input current, an output voltage, or an output current of the power supply module, and the characteristic data of the plurality of LEDs includes bin data, temperature data, current-voltage characteristic data, current-output characteristic data, and junction temperature-output characteristic data related to the plurality of LEDs. 
     In an exemplary embodiment of the present inventive concept, the characteristic data of the plurality of LEDs includes current-voltage characteristic data, current-output characteristic data, and junction temperature-output characteristic data, 
     wherein the controller controls the operation of the power supply module using at least one of the current-voltage characteristic data, the current-output characteristic data, and the junction temperature-output characteristic data related to the plurality of LED elements, and wherein the current-voltage characteristic data, the current-output characteristic data, and the junction temperature-output characteristic data of the plurality of LEDs are stored in a lookup table. 
     In an exemplary embodiment of the present inventive concept, an LED lighting device further includes a communications module included in the MCU, wherein the communications module is connected to an external controller and is configured to communicate with the external controller. 
     In an exemplary embodiment of the present inventive concept, the communications module communicates with the external controller using one of visible light wireless communications (LI-FI), WI-FI, and ZIGBEE. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features and aspects of the present inventive concept will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a block diagram illustrating a Light Emitting Diode (LED) driving device, according to an exemplary embodiment of the present inventive concept; 
         FIG. 2  is a perspective view illustrating an automotive headlamp operated by an LED driving device, according to an exemplary embodiment of the present inventive concept; 
         FIG. 3  is a block diagram illustrating an LED lighting device, according to an exemplary embodiment of the present inventive concept; 
         FIG. 4  illustrates a circuit diagram of the LED lighting device of  FIG. 3 , according to an exemplary embodiment of the present inventive concept; 
         FIG. 5  is a block diagram illustrating an LED lighting device, according to an exemplary embodiment of the present inventive concept; 
         FIG. 6  illustrates a circuit diagram of the LED lighting device of  FIG. 5 , according to an exemplary embodiment of the present inventive concept; 
         FIG. 7  is a diagram illustrating a microcontroller unit (MCU) that may be applied to an LED driving device, according to an exemplary embodiment of the present inventive concept; 
         FIGS. 8 and 9  illustrate an active protection function of an LED driving apparatus, according to an exemplary embodiment of the present inventive concept; 
         FIG. 10  illustrates an active protection function of an LED driving device, according to an exemplary embodiment of the present inventive concept; 
         FIG. 11  illustrates a graph of the active control function of the LED driving device of  FIG. 10 , according to an exemplary embodiment of the present inventive concept; 
         FIG. 12  illustrates a configuration of an automobile to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept; 
         FIG. 13  is a perspective view illustrating a flat lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept; 
         FIG. 14  is an exploded perspective view illustrating a bulb-type lamp as a lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept; 
         FIG. 15  is an exploded perspective view schematically illustrating a bar-type lamp as a lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept; 
         FIG. 16  is an exploded perspective view schematically illustrating a lamp including a communications module as a lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept; and 
         FIGS. 17 to 19  are schematic views illustrating illumination control network systems to which an LED driving device is applied, according to exemplary embodiments of the present inventive concept. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, exemplary embodiments of the present inventive concept will be described in detail with reference to the accompanying drawings. 
     The present inventive concept may, however, be embodied in many different forms, and should not be construed as being limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure is thorough and complete, and will convey the scope of the present inventive concept to those skilled in the art. 
     In the drawings, the shapes and dimensions of elements may be exaggerated for clarity, and like reference numerals may refer to like elements throughout the specification. 
       FIG. 1  is a block diagram illustrating a Light Emitting Diode (LED) driving device, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 1 , an LED driving device  10 , according to an exemplary embodiment of the present inventive concept, may include a power supply module  11 , an information acquisition module  12 , a control module  13 , and the like. The power supply module  11  may be supplied with input power through input terminals A and B, and may discharge output power through output terminals C and D. Input power may be defined as an input voltage V in  and an input current I in , and output power may be defined as an output voltage V out  and output current I out . Output terminals C and D may be connected to a light source  20  having at least one LED element. In an exemplary embodiment of the present inventive concept, the light source  20  may be a light source for lighting devices or an automotive headlamp, and the like, and in a case in which the light source  20  is an automotive headlamp, the light source  20  may include a plurality of LED arrays capable of operating independently of each other. 
     The power supply module  11  may generate output power from input power transmitted through the input terminals A and B. The output power may be power suitable for driving a plurality of the LEDs included in the light source  20 . For example, the power supply module  11  may supply the output current I out  to the light source  20  through the output terminals C and D. 
     The information acquisition module  12  may collect various data from the power supply module  11 . In an exemplary embodiment of the present inventive concept, the information acquisition module  12  may acquire operating data related to the power supply module  11  and characteristic data related to a plurality of LED elements included in the light source  20 . The operating data related to the power supply module  11  may include a portion of the input voltage V in  and the input current I in  being input to the power supply module  11 , and the output voltage V out , and the output current I out  being output from the power supply module  11 . Characteristic data related to a plurality of LED elements may include bin data related to a plurality of LED elements or a temperature of the plurality of LED elements, and the like. The bin data related to the LED elements may have a fixed value, and may be used in calculating a junction temperature, a reference value of forward voltage, and the like, of the LED elements. 
     In an exemplary embodiment of the present inventive concept, the information acquisition module  12  may include a memory. The memory included in the information acquisition module  12  may include a lookup table storing current-voltage characteristic data, current-output characteristic data, or junction temperature-output characteristic data related to the plurality of LED elements. The plurality of LED elements may display current-voltage characteristics, current-output characteristics, junction temperature-output characteristics, and the like, which may be different from each other. The plurality of LED elements may display processing conditions, and the like. The lookup table may store the current-voltage characteristics, the current-output characteristics, the junction temperature-output characteristics, and the like, for each LED element. For example, the bin data related to the LED elements and luminous flux values thereof may be stored in a memory unit in a lookup table such as in Table 1 below. 
     
       
         
           
               
               
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                   
                 Luminous flux 
                 Luminous flux 
                 Luminous flux 
               
               
                   
                 Bin # 
                 minimum value 
                 maximum value 
                 typ. 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 KY 
                 82 
                 97 
                 89.5 
               
               
                   
                 KZ 
                 97 
                 112 
                 104.5 
               
               
                   
                 LX 
                 112 
                 130 
                 121 
               
               
                   
                   
               
            
           
         
       
     
     The current-voltage characteristic, the current-output characteristic, and the junction temperature-output characteristic of each LED element may be represented using a line graph. The line of the graph may have a predetermined curve. For example, the current-voltage characteristic of a particular LED element may be a characteristic of that LED element reflecting a relationship between a current flowing in that LED element and a forward voltage measured in that LED element. When an x-axis of a graph is defined as a voltage level and a y-axis of the graph is defined as the amount of current, the current-voltage characteristic of an LED element may be illustrated in a manner similar to that of a quadratic function, and a lookup table may store data related to the quadratic function representing the current-voltage characteristic of the LED element. 
     The control module  13  may control the operation of the power supply module  11  based on operating data and characteristic data acquired by the information acquisition module  12 . The control module  13  may include an output control module adjusting the output voltage V out  and the output current I out  of the power supply module  11 , a protection module that may block input power supplied to the power supply module  11 , and the like. 
     The output control module may include a Direct Current to Direct Current (DC/DC) controller or a linear controller, and may control operation of the power supply module  11  based on the operating data and the characteristic data provided by the information acquisition module  12 . The output control module may include an arithmetic logic. In a case in which the power supply module  11  includes a DC/DC converter such as a buck converter or a boost converter, the output control module may adjust an output voltage and an output current of the DC/DC converter by adjusting the duty ratio of a switching element included in the DC/DC converter. A linear controller may be connected to a current regulator connected between the light source  20  and a ground terminal, and may adjust the operation of the switching element included in the current regulator. The protection module may selectively block input power input to the power supply module  11  in accordance with an operation status of the power supply module  11  or the light source  20 . 
     The information acquisition module  12  and the control module  13  may be included in a single (MCU)  14 . The information acquisition module  12  and the control module  13  may be included in a programmable MCU  14 , and may provide various functions with a program executed in the MCU  14 . For example, in the case of the light source  20  being an automotive headlamp, operating characteristics of the headlamp set forth in guidelines applicable to automotive lighting, and the like, may differ from one country to another in which automobiles equipped with the headlamp are sold. In this case, light having a desired property may be output by a headlamp by inputting a new program to the MCU  14  or inputting new parameter values for the same program, without having to design new hardware to drive the headlamp. 
     In addition, since the MCU  14  has a calculating function, the MCU  14  may protect the LED elements included in the light source  20  and increase power efficiency by actively setting a threshold value of current and voltage in accordance with operating conditions of the light source  20 . According to an exemplary embodiment of the present inventive concept, the power supply module  11 , the information acquisition module  12  and the control module  13  may be included in the MCU  14 . In this case, the power supply module  11  of a wide range of topologies, such as a buck converter, a boost converter, a buck-boost converter, a flyback converter, and the like, may be implemented without hardware changes in accordance with a program running in the MCU  14 . 
       FIG. 2  is a perspective view illustrating an automotive headlamp operated by an LED driving device, according to an exemplary embodiment of the present inventive concept. The LED driving device, according to various exemplary embodiments of the present inventive concept, may be capable of operating a light source including one or more LED elements, in addition to operating the automotive headlamp illustrated in  FIG. 2 . An automotive headlamp  30 , illustrated in  FIG. 2 , may include the light source  20  operated by the LED driving device  10  illustrated in  FIG. 1 . 
     With reference to  FIG. 2 , the automotive headlamp  30 , according to an exemplary embodiment of the present inventive concept, may include a plurality of light sources emitting light for different uses with respect to each other. The automotive headlamp  30  may include low beam lights  31  and  32 , high beam lights  33 , cornering lights  34 , daytime running lights (DRL)  35 , turn signal lights  36 , and the like. The respective light sources  31  to  36  may be provided in the automobile headlamp  30  for the uses differing from each other, and may respectively include LED elements of different colors or different numbers of LED elements. Therefore, the voltage and current required for the operation of the respective light sources  31  to  36  may also differ from each other. 
     In a case of operating the respective light sources  31  to  36  using only hardware, the respective light sources  31  to  36  may require at least one power supply circuit and a control circuit for controlling the power supply circuit, a car battery or a filter circuit for filtering power supplied from a generator, and the like. Therefore, the overall circuit complexity and manufacturing costs may be significantly increased, resulting in difficulty in maintenance and repairs. Also, in a case of a geographical region being changed through automobile exports, and the like, it may be difficult to adjust the optical axis, brightness, and the like, of the respective light sources  31  to  36  in accordance with the relevant guidelines. 
     According to an exemplary embodiment of the present inventive concept, the respective operations of the plurality of light sources  31  to  36  included in the automotive headlamp  30  may be controlled by a single MCU. Since operating characteristics of the respective light sources  31  to  36 , for example, the brightness or optical axis thereof, may be modified with a program running in the MCU, light being output by the light sources  31  to  36  may be adjusted to meet a variety of desired conditions without altering the hardware design. In addition, optimized driving power may be supplied to the turned-on light sources  31  to  36  by actively setting a voltage threshold value or a current threshold value differently according to the turned on light sources  31  to  36 . 
       FIG. 3  is a block diagram illustrating an LED lighting device, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 3 , an LED lighting device  100 , according to an exemplary embodiment of the present inventive concept, may include a light source  110 , a power supply module  120  supplying driving power to the light source  110 , an MCU  130  controlling the operation of the power supply module  120 , and the like. The LED lighting device  100 , according to an exemplary embodiment of the present inventive concept, with reference to  FIG. 3 , illustrates an automotive headlamp. However, the LED lighting device  100  may also be a lighting device included in a range of industrial and household lighting devices. 
     The light source  110  may include a plurality of LED modules. The plurality of LED modules may each include at least one or more LED arrays. For example, an LED module includes first, second, third, and fourth LED arrays  112 ,  114 ,  116  and  118 , respectively, and the first to fourth LED arrays  112  to  118  may have different operating characteristics with respect to each other. For example, the first to fourth LED arrays  112  to  118  may output light of different colors or different levels of brightness with respect to each other. The first to fourth LED arrays  112  to  118  may include different numbers of LED elements with respect to each other. Since the first to fourth LED arrays  112  to  118  may output light of different characteristics with respect to each other, the first to fourth LED arrays  112  to  118  may respectively be applied to light sources (e.g., low beam lights, high beam lights, turn signal lights, daytime running lights, fog lights, and the like) with different purposes with respect to each other. 
     The power supply module  120  may supply driving power to the first to fourth LED arrays  112  to  118 . In an exemplary embodiment of the present inventive concept, with reference to  FIG. 3 , the input power for generating driving power is generated from a battery or a generator provided in an automobile, and thus, the power supply module  120  may include a DC/DC converter. The power supply module  120  may include first, second, third, and fourth power supply modules  122 ,  124 ,  126 , and  128  supplying a driving power to the first to fourth LED arrays  112  to  118 , respectively. The first to fourth power supply modules  122  to  128  may all be implemented as DC/DC converters having the same topology, or may be implemented as DC/DC converters having different topologies. 
     An MCU  130  may include an information acquisition module  140 , a control module  150 , and the like. The information acquisition module  140  may include a circuit detecting bin data related to the LED elements included in the first to fourth LED arrays  112  to  118 , a temperature of the LED elements, an input/output voltage, an input/output current of the first to fourth power supply modules  122  to  128 , and the like. 
     The control module  150  may include the first to fourth output control modules  152  to  158 . The first to fourth output control modules  152  to  158  included in the control module  150  may correspond to the first to fourth power supply modules  122  to  128 , respectively. The first to fourth output control modules  152  to  158  may respectively adjust the duty ratio of the switching element included in a DC/DC converter in order to adjust the output current and the output voltage of the DC/DC converter included in the first to fourth power supply modules  122  to  128 . 
     The duty ratio value adjusted by the first to fourth output control modules  152  to  158  may be determined by the temperature of LED elements of the light source  110  detected by the information acquisition module  140 , bin data, the input/output voltage and input/output current of the first to fourth power supply modules  122  to  128 , and the like. For example, in a case in which the output current is reduced from an increase in temperature of LED elements included in the second LED array  114 , to prevent the decline of output of the second LED array  114 , the second output control module  154  may increase the duty ratio value supplied to the second power supply module  124 . The MCU  130  may actively control the driving power supplied to the LED elements of the LED arrays  112  to  118  according to changes in the operating conditions and environmental conditions of the LED elements included in the light source  110 , and may increase operating efficiency and prevent lifespan shortages of the LED elements included in the LED arrays  112  to  118 . 
     Input power required by the power supply module  120  to supply driving power to the light source  110  may be transmitted by a battery  180  of an automobile, and the like. The battery  180  may output a V BAT  voltage. Power output by the battery  180  may be transmitted to the MCU  130  through a filter  160  after being converted to a voltage adequate for an operation of the MCU  130  by a body control module  170 . The MCU  130  and the body control module  170  may be connected by a specific communications interface method such as a Controller Area Network (CAN) protocol, and the like, to allow for communications. In addition to CAN, other protocols such as a Local Interconnect Network (LIN) protocol, a FLEXRAY protocol, and the like, may be applied to communications between the MCU  130  and the body control module  170 . 
       FIG. 4  illustrates a circuit diagram of the LED lighting device of  FIG. 3 , according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 4 , an LED lighting device  100 , according to an exemplary embodiment of the present inventive concept, may include a battery  180  supplying Direct Current (DC) power, a filter  160  for removing noise components from the DC power being output by the battery  180 , first, second, third, and fourth LED arrays  112 ,  114 ,  116 , and  118 , first, second, third, and fourth power supply modules  122 ,  124 ,  126 , and  128  supplying driving power to the respective LED arrays  122  to  128 , an MCU  130  controlling the operation of the respective power supply modules  122  to  128 , and the like. Power required for the operation of the MCU  130  may be supplied by a regulator  190  using DC power passed through the filter  160 . 
     The MCU  130  may be connected to allow communications with a body control module  170  via a communications module  135 . As described above, the MCU  130  and the body control module  170  may be connected to each other by a communications protocol such as CAN, LIN, FLEXRAY, and the like. The body control module  170  may transmit vehicle operating data, and the like, to the MCU  130  via the communications module  135 , and an information acquisition module  140  may collect vehicle operating data, and the like, transmitted by the body control module  170 . The vehicle operating data may include vehicle driving environment conditions, for example, amount of sunlight, precipitation, vehicle operating speed, steering wheel operating conditions, and the like. 
     The information acquisition module  140  may include a bin information detector  142 , a temperature detector  144 , a monitoring unit  146 , a memory  148 , and the like. The bin information detector  142  may detect bin data related to the LED elements included in the first to fourth LED arrays  112  to  118 , and the temperature detector  144  may measure the temperature of the LED elements included in the first to fourth LED arrays  112  to  118 . Therefore, the bin information detector  142  may be connected to a bin resistor of the LED elements included in the first to fourth LED arrays  112  to  118 , and the temperature detector  144  may be connected to a thermistor connected to the LED elements included in the first to fourth LED arrays  112  to  118 . 
     The monitoring unit  146  may detect an input/output voltage, an input/output current, and the like, of the first to fourth power supply modules  122  to  128 . The memory  148  may store characteristic data related to the LED elements included in the first to fourth LED arrays  112  to  118 , for example, current-voltage characteristic data, current-output characteristic data, junction temperature-output characteristic data, or the like, of the LED elements. The characteristic data may be stored in a lookup table form in the memory  148 . 
     Data acquired by the information acquisition module  140  may be transmitted to a control module  150 . The control module  150  may include first, second, third, and fourth output control modules  152 ,  154 ,  156 , and  158 , and the first to fourth output control modules  152  to  158  may adjust the output of the DC/DC converter included in each of the first to fourth power supply modules  122  to  128 , respectively. In an exemplary embodiment of the present inventive concept, the first to fourth output control modules  152  to  158  may each include a DC/DC controller. 
     The first to fourth power supply modules  122  to  128  may include a DC/DC converter. Referring to  FIG. 4 , the first and the second power supply modules  122  and  124  may include a boost converter, the third power supply module  126  may include a buck converter, and the fourth power supply module  128  may include a full-bridge converter. In the case in which the first to fourth power supply modules  122  to  128  include a DC/DC converter of a topology described above, the first to fourth LED arrays  112  to  118  may be applied sequentially as light sources for low beam lights, high beam lights, daytime running lights, and turn signal lights. The first to fourth output control modules  152  to  158  may respectively include a pulse-width modulation (PWM) signal generating circuit, an analog to digital converter (ADC) circuit, a digital to analog converter (DAC) circuit, a comparator, or the like. 
     In an exemplary embodiment of the present inventive concept, with reference to  FIG. 4 , the first to fourth LED arrays  112  to  118  may respectively be operated by the first to fourth power supply modules  122  to  128 . Since each of the first to fourth LED arrays  112  to  118  may operate by being supplied with different amounts of driving power, the respective LED arrays  112  to  118  can be operated with high efficiency. In addition, external environmental conditions and operating conditions may be detected by a program running in the MCU  130 , and the driving power supplied to each of the respective LED arrays  112  to  118  may be actively excluded accordingly. The first to fourth power supply modules  122  to  128  may be provided in a modularized state together with the MCU  130 . 
       FIG. 5  is a block diagram illustrating an LED lighting device, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 5 , an LED lighting device  200 , according to an exemplary embodiment of the present inventive concept, may include a light source  210 , a power supply module  220 , an MCU  230 , and the like. As described above with reference to  FIG. 3 , power required for the operation of the light source  210  and the MCU  230  may be transmitted by a battery  280  of an automobile. An output voltage V BAT  of the battery  280  may be converted to an appropriate voltage by a body control module  270  and transmitted to the MCU  230 , the power supply module  220 , and the like, after passing through a filter  260 . 
     The light source  210  may include a plurality of LED arrays such as the first, second, third, and fourth LED arrays  212 ,  214 ,  216 , and  218 . Although in an exemplary embodiment of the present inventive concept the light source  210  is illustrated as including the first to fourth LED arrays  212  to  218 , the present inventive concept is not limited thereto. For example, the first to fourth LED arrays  212  to  218  may be provided as light sources for different uses with respect to each other, and may output light having different colors, different levels of brightness, and the like, with respect to each other. For example, when the first LED array  212  is used to provide a low beam of an automotive headlamp and the second LED array  214  is used to provide a high beam of an automotive headlamp, the second LED array  214  may output light with higher intensity than that of the first LED array  212  at a high optical axis. 
     The LED lighting device  200  illustrated in  FIG. 5  may have a smaller number of power supply modules  220  than the number of the plurality of LED arrays  212  to  218  included in the light source  210 . Referring to  FIG. 5 , a single power supply module  220  supplies driving power to the plurality of LED arrays  212  to  218 , and the operation of the power supply module  220  may be controlled by the MCU  230 . 
     The MCU  230  may include an information acquisition module  240 , a control module  250 , and the like. The information acquisition module  240  and the control module  250  may be provided as a single MCU  230 , and according to an exemplary embodiment of the present inventive concept, the power supply module  220  may also be provided in a single MCU  230  together with the information acquisition module  240  and the control module  250 . 
     The information acquisition module  240  may acquire bin data and temperature of LED elements included in the plurality of LED arrays  212  to  218 , the input/output voltage, the input/output current, and the like, of the power supply module  220 . The control module  250  may adjust the operation of the plurality of LED arrays  212  to  218  by controlling the operation of the power supply module  220 , based on the data acquired by the information acquisition module  240 . 
     The control module  250  may include a DC/DC controller  252  and a linear controller  254 . In an exemplary embodiment of the present invention, the DC/DC controller  252  may be a circuit controlling the operation of the DC/DC converter included in the power supply module  220 , capable of changing a level of power output from the power supply module  220  by controlling a duty ratio of a switching element included in the DC/DC converter. The linear controller  254  may be a circuit linearly controlling the output of the power supply module  220 . In an exemplary embodiment of the present inventive concept, the linear controller  254  may control an operation of a current regulator disposed between the respective LED arrays  212  to  218  and a ground terminal. For example, in the circuit diagram illustrated in  FIG. 5 , the power supply module  220  may include a current regulator together with a DC/DC converter. 
     The MCU  230  may be connected to the body control module  270  to allow communications through a communications protocol such as CAN, LIN, FLEXRAY, and the like. The MCU  230  may perform an active control such as changing the optical axis of the LED arrays  212  to  218  or increasing or decreasing the amount of light that is output from the LED arrays  212  to  218 , respectively, based on the automobile operating data received from the body control module  270 . 
       FIG. 6  illustrates a circuit diagram of the LED lighting device of  FIG. 5 , according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 6 , the input power required for the operation of the LED lighting device  200  may be output by the battery  280  of an automobile and transmitted to the filter  260 . The input power from which noise components have been removed by the filter  260  may be converted to the appropriate power for operating the MCU  230  in the regulator  290  and may be input to the MCU  230 . The input power passed through the filter  260  may be transmitted to a DC/DC converter  222 . 
     Although the DC/DC converter  222  in  FIG. 6  is illustrated as a buck converter, the DC/DC converter  222  may also include a different type of boost converter, a buck-boost converter, and the like. The operation of the DC/DC converter  222  may be controlled by a DC/DC controller  252  included in the MCU  230 . The DC/DC controller  252  may supply a PWM signal to a control terminal of a switching element included in the DC/DC converter  222 , and the output of the DC/DC converter  222  may increase or decrease according to a duty ratio of the PWM signal. The driving power output by the DC/DC converter  222  may be supplied to the plurality of LED arrays  212  to  218  connected to each other in parallel. 
     The DC/DC controller  252  may adjust a switching frequency of the DC/DC converter  222  using a software program. In a case in which the LED lighting device  200 , according to an exemplary embodiment of the present inventive concept, is applied to an automotive headlamp, an electromagnetic wave condition required for each car model may be different. In an exemplary embodiment of the present inventive concept, the DC/DC controller  252  may control the switching frequency of the DC/DC converter  222  according to a spread spectrum scheme by using a software program. Here, the scope of the spread spectrum may not be assigned as a fixed value, and may be changed depending on the software settings. 
     A current regulator  224  may be disposed between the plurality of LED arrays  212  to  218  connected to each other in parallel and the ground terminal. The current regulator  224  may include a switching element and a resistor as circuits supplying constant current to the plurality of LED arrays  212  to  218 . The operation of the plurality of LED arrays  212  to  218  may be controlled by a linear controller  254  included in the MCU  230 . 
     The MCU  230  may include a communications unit  235  connected to a body control module  270  to allow communications, an information acquisition module  240 , and a control module  250 . As described above, the control module  250  may include the DC/DC controller  252 , and the linear controller  254  controlling the operations of the DC/DC converter  222  and the current regulator  224 . 
     The information acquisition module  240  may include a bin information detector  242  collecting bin data related to the LED elements included in the LED arrays  212  to  218 , a temperature detector  244  measuring temperatures of the LED elements, a monitoring unit  246  detecting input/output voltage, input/output current information, and the like, of the current regulator  224  and the DC/DC converter  222 , a memory  248 , and the like. The memory  248  may store a lookup table recording the current-voltage characteristic data, the current-output characteristic data, or the junction temperature-output characteristic data related to the LED elements. 
       FIG. 7  is a diagram illustrating an MCU that may be applied to an LED driving device, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 7 , an MCU  300  may include a monitoring unit  310 , a bin information detector  320 , a temperature detector  330 , a memory  340 , a protection module  350 , an output control module  360 , a communications module  370 , and the like. The output control module  360  may include a DC/DC controller  362  and a linear controller  364 , and the level of an output voltage V OUT  and a current I OUT  supplied to an LED array  380  may be adjusted by the output control module  360 . 
     A power supply module  390  supplying the output voltage V OUT  and the output current I OUT  to the LED array  380  may include a DC/DC converter  392 , a current regulator  394 , and the like.  FIG. 7  illustrates a DC/DC converter  392  implemented as a boost converter topology by an inductor L 1 , a switching element Q 2 , a diode D 1 , and a capacitor C 1 . The DC/DC converter  392  may also be implemented as a range of topologies such as a buck converter, a buck-boost converter, a Single-Ended Primary-Inductor Converter (SEPIC) converter, and the like, instead of the a boost converter. Resistors R 1 , R 2  and R 3  included within the DC/DC converter  392  may be provided as resistors for monitoring the operating status of the DC/DC converter  392  by the monitoring unit  310 . The current regulator  394  having a switch element Q 3  and a resistor R 4  may be disposed between the LED array  380  and the ground terminal. 
     The bin information detector  320  may detect bin data related to LED elements included in the LED array  380  by being connected electrically to a bin resistor, and the temperature detector  330  may detect the temperature of the LED array  380  by being connected to a thermistor. Bin data and the temperature of the LED elements may be transmitted to the output control module  360  to control the output voltage V OUT  and the output current I OUT  transmitted to the LED array  380 , or may be used for preventing damage to the LED elements, and to protect the LED elements. 
     The memory  340  may store current-voltage characteristic data, junction temperature-current characteristic data, current-output characteristic data, and the like, of the LED elements. The memory  340  may store the characteristic data related to the LED elements in the form of a lookup table. The output control module  360  may control the output voltage V OUT  and the current I OUT  with reference to the characteristic data stored in the memory  340 . 
     The protection module  350  may be a module provided to prevent damage to the LED array  380 , the DC/DC converter, and the like, and may be connected to a control terminal of a switching element Q 1  included in the power supply module  390 . For example, in a case in which the temperature detected by the temperature detector  330  is close to or exceeds a temperature limit of the LED elements, the protection module  350  turns the switching element Q 1  off to block an input voltage V BAT  from being delivered to the DC/DC converter  392  to protect the LED array  380 . The LED array  380  and the DC/DC converter  392  may be protected by operating the protection module  350  under a range of conditions in addition to temperature. 
     The output control module  360  may include a DC/DC controller  362  and a linear controller  364 . The DC/DC controller  362  may control the duty ratio and the switching frequency of the switching element Q 2  that determines the output of the DC/DC converter  392 , and the linear controller  364  may control the operation of a switching element Q 3  included in the current regulator  394 . The output control module  360  may include an arithmetic logic  366  controlling operations of the switching elements Q 2  and Q 3  based on characteristic data read from the memory  340 , operating data related to the power supply module  390 , and the like, detected by the monitoring unit  310 . The arithmetic logic  366  may control operations of the switching elements Q 2  and Q 3  by controlling outputs of the DC/DC controller  362  and the linear controller  364 . 
     The operations of the switching elements Q 2  and Q 3  may be controlled by the arithmetic logic  366  included in the output control module  360 , and the operations of the switching elements Q 2  and Q 3  may be controlled by a software program programmed in the arithmetic logic  366 . For example, since the output of the LED array  380  may change according to the software program running in the arithmetic logic  366 , the operation of the LED array  380  may be changed by modifying only the software running in the arithmetic logic  366 . Therefore, an LED lighting device meeting customers&#39; requirements and various guidelines may be provided by a software program modification alone, without the LED lighting device having to be redesigned or going through a change in hardware. 
     The arithmetic logic  366  included in the output control module  360  may control the operation of the protection module  350 . The arithmetic logic  366  of the output control module  360  may set a threshold value for a plurality of parameters based on characteristic data read from the memory unit  340 , operating data related to the power supply module  390  detected by the monitoring unit  310 , and temperature and bin data detected by the temperature detector  330  and the bin information detector  320 . The protection module  350  may adjust the operation of the switching element Q 1  by comparing an actual measured value for each parameter to the threshold value set by the arithmetic logic  366 . Thus, the LED elements may be actively protected according to the operating conditions and the environmental conditions that the LED elements are exposed to. 
     The communications module  370  may be provided as a module for communicating with an external controller provided separately with the MCU  300 . For example, in a case in which the LED array  380  is provided partly as a light source of an automotive headlamp, the communications module  370  may be provided as a module for mediating communications between the MCU  300  and the body control module of the vehicle. The communications module  370  may operate according to various communications protocols such as Inter-Integrated Circuit (I2C), Serial Peripheral Interface (SPI), CAN, LIN, FLEXRAY, Media Oriented Systems Transport (MOST), and the like. 
       FIGS. 8 and 9  illustrate an active protection function of an LED driving device, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 8 , an LED driving device  400 , according to an exemplary embodiment of the present inventive concept, may include a DC/DC converter  410  applying a driving voltage to a light source  440  including a plurality of LED arrays, for example, a first LED array  442 , a second LED array  444 , a third LED array  446 , and a fourth LED array  448 , an operational amplifier  420  providing a reference signal ref to the DC/DC converter  410 , and a multiplexer (MUX) circuit  430  selecting a signal applied to the input terminal of the operational amplifier  420 . The DC/DC converter  410 , as described previously, may be implemented in various topologies, such as a buck converter, a boost converter, a buck-boost converter, a SEPIC converter, a ZETA converter, and the like. The operation of the MUX circuit  430  may be controlled by a control signal MCU_CH provided by the above-described MCU  300 . 
     The light source  440  may include the first and fourth LED arrays  442  to  448  connected to each other in parallel, and a current regulator may be connected between the first to fourth LED arrays  442  to  448  and the ground terminal. The number of LED arrays included in the light source  440  may be modified to be different from the number of LED arrays (e.g., the first to fourth LED arrays  442  to  448 ) shown in  FIG. 8 . In an exemplary embodiment of the present inventive concept, in a case in which the light source  440  is provided as an automotive headlamp, the first to fourth LED arrays  442  to  448  may be light sources provided with different roles with respect to each other, such as low beam lights, high beam lights, turn signal lights, daytime running lights, a positioning lamp, a fog lamp, and the like. In a case in which the light source  440  is provided as household lighting, the first to fourth LED arrays  442  to  448  may be light sources disposed in different locations with respect to each other, such as living room lighting, bathroom lighting, kitchen lighting, master bedroom lighting, porch lighting, and the like. 
     The first to fourth LED arrays  442  to  448  may be light sources provided for different functions and purposes with respect to each other, and may emit light of different colors or different levels of brightness with respect to each other. Therefore, as in an exemplary embodiment of the present inventive concept, with reference to  FIG. 8 , the first to fourth LED arrays  442  to  448  may include different numbers of LED elements with respect to each other.  FIG. 8  illustrates the first LED array  442  including the most number of LED elements when compared to the second, third, and fourth LED arrays  444 ,  446 , and  448 , and the fourth LED array  448  including the least number of LED elements when compared to the first, second and third LED arrays  442 ,  444 , and  446 , but the number of LED elements included in the LED arrays is not limited thereto. 
     Since the first to fourth LED arrays  442  to  448  have different numbers of LED elements with respect to each other, an output voltage V out  of the DC/DC converter  410  may be output at a level appropriate for an LED array that is actually turned on in the LED arrays  442  to  448 , to increase power efficiency and to reduce stress applied to the LED elements. For example, when the first LED array  442  is turned on, the DC/DC converter  410  may output a sufficient level of the output voltage V out1  to drive the first LED array  442 . When the first LED array  442  is not turned on and the second LED array  444  is turned on, the DC/DC converter  410  may output an output voltage V out2  having a level lower than that of the output voltage V out1 . 
     For the DC/DC converter  410  to actively adjust the level of the output voltage V out  according to the characteristics of the turned-on first to fourth LED arrays  442  to  448 , the operational amplifier  420  and the MUX circuit  430  may provide the reference signal ref determined according to the characteristics of the turned-on first to fourth LED arrays  442  to  448  to the DC/DC converter  410 . For driving the respective first to fourth LED arrays  442  to  448 , a forward voltage (Vf) determined by the number of LED elements included in each of the respective first to fourth LED arrays  442  to  448 , and a headroom voltage (Vhr) required for the operation of constant current, may be required. Thus, when the forward voltages of the individual LED elements included in each of the respective first to fourth LED arrays  442  to  448  are all equal, the output voltages V out1  to V out4  required for driving the respective first to fourth LED arrays  442  to  448  may be determined using the following Formula 1: 
         V   out1 =5· Vf+Vhr  
 
         V   out2 =4· Vf+Vhr  
 
         V   out3 =3· Vf+Vhr  
 
         V   out4 =2· Vf+Vhr   [Formula 1]
 
     The output voltage V OUT1  required for driving the first LED array  442  may have the highest level, and the output voltage V OUT4  required for driving the fourth LED array  448  may have the lowest level. 
     When the first LED array  442  is turned on in the light source  440 , a high signal may be transmitted to an input terminal HR 1  of the MUX circuit  430 . Similarly, when the second to fourth LED arrays  444  to  448  are respectively turned on, a high signal may be transmitted to input terminals HR 2  to HR 4  of the MUX circuit  430 . The MUX circuit  430  may transmit the input signals transmitted to the respective input terminals HR 1  TO HR 4  to the operational amplifier  420 , and the operational amplifier  420  may compare the transmitted inputs with a reference voltage V REF  and may transmit the comparison result to the DC/DC converter  410 . The DC/DC converter  410  may receive the output of the current output voltage V OUT  and the output of the operational amplifier  420  through resistors R 1  to R 3 , which may be used as the reference signal ref Hereinafter, the active protective function of the LED driving device  400  will be described in detail with reference to  FIG. 9 . 
     Referring to  FIG. 9 , levels of the output voltages V OUT  are shown with respect to time in a graph, according to an exemplary embodiment of the present inventive concept. The levels of the output voltages V OUT  of a comparative example are shown with respect to time in the graph of  FIG. 9 . Line  1  of the graph of  FIG. 9  may correspond to the output voltage V OUT  in an example in which the first LED array  442 , the second LED array  444 , and the third LED array  446  are turned off sequentially as time passes, in a state where the first to fourth LED arrays  442  to  448  are all turned on, according to an exemplary embodiment of the present inventive concept. Alternatively, line  1  of the graph of  FIG. 9  may correspond to an example in which the output voltage V OUT  of the first to fourth LED arrays  442  to  448  are sequentially turned on, respectively, as time passes, according to an exemplary embodiment of the present inventive concept. 
     Line  2  of  FIG. 9  shows the levels of the output voltages V OUT  of a comparative example. In examining the comparative example, regardless of elapsed time, for example, regardless of the time in which the first to fourth LED arrays  442  to  448  are turned on, the output voltage V OUT  of the DC/DC converter  410  may be constantly maintained. Thus, the output voltage V OUT  of the DC/DC converter  410  needs to have a high level capable of driving the first LED array  442  that requires the highest driving voltage 5*Vf+Vhr, and consequently, in a case in which the first LED array  442  is turned on, power efficiency may be reduced. 
     In an exemplary embodiment of the present inventive concept, the output voltage V OUT  of the DC/DC converter  410  may be controlled actively in accordance with the turned-on first to fourth LED arrays  442  to  448 . As illustrated in  FIG. 9 , the output voltage V OUT  corresponding to the level 5*Vf+Vhr required for driving the first LED array  442  may be generated during a time interval in which the first LED  442  is turned on. Since the first to fourth LED arrays  442  to  448  are connected to each other in parallel and receive the output voltage V OUT , the second to fourth LED arrays  444  to  448  may also be turned on together while the output voltage V OUT  corresponding to 5*Vf+Vhr is applied to the first LED array. In this case, to reduce the stress applied to the LED elements included in the second to fourth LED arrays  444  to  448 , and the second to fourth LED arrays  444  to  448  may be connected to at least one dummy diode. 
     In a case of turning on the second LED array  444  without turning on the first LED array, the output voltage V OUT  of a level corresponding to 4*Vf+Vhr may be output as illustrated in a second interval of  FIG. 9 . Thus, the first LED array  442  may not be turned on, and the second to the fourth LED arrays  444  to  448  may be turned on. As in the previous case, the third and fourth LED arrays  446  and  448  may be selectively connected to a dummy diode to protect the LED elements. 
     In an exemplary embodiment of the present inventive concept, the DC/DC converter  410  may actively control the level of the output voltage V OUT  so that the output voltage V OUT  corresponds to a voltage level adequate to turn on the LED array among the first to fourth LED arrays  442  to  448  requiring the highest driving voltage to be turned on. Therefore, power efficiency may be increased and stress applied to the LED elements may be reduced. 
       FIG. 10  illustrates an active protection function of an LED driving device, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 10 , an LED driving device  500 , according to an exemplary embodiment of the present inventive concept, may include power supply modules  522  and  524  supplying driving power to a light source  510  including a plurality of LED arrays, for example, first, second, third, and fourth LED arrays  512 ,  514 ,  516 , and  518 , a control module  530  controlling operations of the power supply modules  522  and  524 , information acquisition modules  540  to  560  collecting and providing data required to control the operations of the power supply modules  522  and  524  by the control module  530 , and the like. The power supply module  522  may be referred to as a DC/DC converter  522 . The information acquisition module  560  may be referred to as a temperature detector  560 . 
     Power required for the operation of the LED driving device  500  may be supplied from a power unit  580 . When the light source  510  is provided for an automotive headlamp, an output voltage V BAT  of the power unit  580  may be a DC voltage in a range of approximately 9V-16V. In a case in which the light source  510  is provided for a household lighting system, the power unit  580  may output alternating current (AC) power. A filter unit may remove noise components, and the like, included in power output by the power unit  580 . 
     The power removed of noise components by the filter unit may be input to an input power detector  550  and the DC/DC converter  522 . The input power detector  550  may detect an input voltage and an input current transmitted to the DC/DC converter  522 , and may transmit the input voltage and the input current to input channels  1  and  2 , CH 1  and CH 2 , of an MUX circuit  531  included in the control module  530 , respectively. The DC/DC converter  522  may generate driving power required for the operation of the first to fourth LED arrays  512  to  518  included in the light source  510  by using the input power. The DC/DC converter  522  may be illustrated as a boost converter in  FIG. 10 , but may also be implemented in various topologies such as a buck converter, a buck-boost converter, a SEPIC converter, a ZETA converter, and the like. 
     The level of the driving power output by the DC/DC converter  522  may be determined by the duty ratio of a PWM signal applied to a control terminal of a switching element Q 2  included in the DC/DC converter  522 . A peak current may be detected in an output terminal of the switching element Q 2  included in the DC/DC converter  522 , and the detected peak current may be transmitted to an input channel  3  CH 3  of the MUX circuit  531 . The output voltage V OUT  generated by the DC/DC converter  522  may be detected by a voltage divider and transmitted to an input channel  4  CH 4  of the MUX circuit  531 . 
     The information acquisition module  540  may also be referred to as an output power detector  540 . The output power detector  540  may be provided between an output terminal of the DC/DC converter  522  and the light source  510 . The output power detector  540  may include a current detector circuit as in the input power detector  550 . The output current of the DC/DC converter  522  may be detected via an output terminal of an operational amplifier included in the output power detector  540 , and the detected output current may be transmitted to an input channel  5  CH 5  of the MUX circuit  531 . 
     The power supply module  524  may be referred to as a current regulator  524 . The current regulator  524  may be connected between each of the first to fourth LED arrays  512  to  518  included in the light source  510  and a ground terminal. A voltage measured from a node between the current regulator  524  and the respective first to fourth LED arrays  512  to  518  may correspond to a headroom voltage required for driving constant current of the respective first to fourth LED arrays  512  to  518 . The headroom voltage of the first to fourth LED arrays  512  to  518  may be respectively input to input channels  6 ,  7 ,  8 , and to  9 , CH 6 , CH 7 , CH 8 , and CH 9  of the MUX circuit  531 . The operation of the respective switching elements included in the current regulator  524  may be controlled by a blocking circuit  535 . Temperature data related to the first to fourth LED arrays  512  to  518  determined from a thermistor included in the temperature detector  560  may be transmitted to input channels  10 ,  11 ,  12 , and  13 , CH 10 , CH 11 , CH 12 , and CH 13  of the MUX circuit  531 . 
     The input/output voltage, the input/output current, and the peak current of the DC/DC converter  522 , the headroom voltage of the first to fourth LED arrays  512  to  518 , the temperature data related to the first to fourth LED arrays  512  to  518 , and the like, measured from the current regulator  524 , may be transmitted to the plurality of input channels CH 1  to CH 13  of the MUX circuit  531 . Additionally, bin data acquired from LED elements included in each of the first to fourth LED arrays  512  to  518  may be input to the MUX circuit  531 . 
     The data input to the MUX circuit  531  may be converted into digital data by an ADC converter  533 , and may be transmitted to an arithmetic logic  537 . The arithmetic logic  537  may be capable of determining whether the first to fourth LED arrays  512  to  518  included in the light source  510  are operating normally based on the received data transmitted by the ADC converter  533 . In a case in which the first to fourth LED arrays  512  to  518  are not determined to be operating normally, the arithmetic logic  537  may adjust operations of the DC/DC converter  522  and the current regulator  524  through the blocking circuit  535 . 
     For example, when the input voltage detected by the input power detector  550  is determined to be high, the arithmetic logic  537  may block power supplied to the DC/DC converter  522  by turning off a switching element Q 1  included in the input power detector  550  through the blocking circuit  535 . In a case in which the voltage V OUT  output by the DC/DC converter  522  is determined to be low, the arithmetic logic  537  may increase a duty ratio of the PWM signal input to the switching element Q 2 . The MUX  531  includes an output unit  539  connected to the arithmetic logic  537 . A voltage reference circuit  590  provides reference voltages to the arithmetic logic  537 . 
       FIG. 11  illustrates a graph of the active control function of the LED driving device of  FIG. 10 , according to an exemplary embodiment of the present inventive concept. Referring to  FIG. 11 , a method for setting a threshold value of the output current, the output voltage, the input current, and the peak current for five cases is illustrated. In the four graphs illustrated in  FIG. 11 , the bold lines represents an upper threshold of the output current in Amperes, the output voltage in Volts, the input current in Amperes, and the peak current in Amperes, respectively, for five cases illustrated below in table 2. In  FIG. 11 , the thin lines represents a lower threshold of the output current in Amperes, the output voltage in Volts, the input current in Amperes, and the peak current in Amperes, respectively, for the five cases illustrated below in table 2. The five cases illustrated in  FIG. 11  are also illustrated in Table 2 below. The light source  510  is assumed to be an automotive headlamp, and the first to fourth LED arrays  512  to  518  are assumed to be provided as low beam lights, high beam lights, daytime running lights, and turn signal lights, respectively. 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 Case 
                 Case 1 
                 Case 2 
                 Case 3 
                 Case 4 
                 Case 5 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
            
               
                 Operating 
                 Low Beam 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 OFF 
               
               
                 Condition 
                 High Beam 
                 ON 
                 ON 
                 ON 
                 OFF 
                 OFF 
               
               
                   
                 DRL 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 ON 
               
               
                   
                 Turn Signal 
                 ON 
                 OFF 
                 OFF 
                 ON 
                 OFF 
               
            
           
           
               
               
               
               
               
               
            
               
                 Output Current(A) 
                 1.05 
                 0.72 
                 0.62 
                 0.34 
                 0.29 
               
               
                 Output Voltage(V) 
                 35.8 
                 35.8 
                 35.8 
                 21.8 
                 18.9 
               
               
                 Input Current(A) 
                 5.25 
                 2.68 
                 2.78 
                 0.61 
                 0.63 
               
               
                 Peak Current(A) 
                 4.20 
                 2.14 
                 2.22 
                 0.49 
                 0.50 
               
               
                 Input Voltage(V) 
                 9 
                 12 
                 10 
                 15 
                 11 
               
               
                 Duty Ratio(%) 
                 75 
                 67 
                 72 
                 31 
                 42 
               
               
                 Operation Efficiency(%) 
                 80 
                 80 
                 80 
                 80 
                 80 
               
               
                   
               
            
           
         
       
     
     In comparing Case 2 and Case 4 from Table 1, the output current, the output voltage, the input current, the peak current, the output voltage, and the duty ratio of Case 2 are all larger than those of Case 4. Since both the low beam and the high beam lights in Case 2 are in a turned-on condition, a large number of LED elements are turned on to output light having a high level of high luminance, and thus, a high level of output voltage and output current may be required. In case 4, since all of the low beam, the high beam, and the DRL are in a turned-off condition, and only the turn-signal is in a turned-on condition, the driving of the light source  510  may be enabled with a low level of output current and output voltage. 
     Referring to the graph of  FIG. 11 , Cases 1 to 5 are divided according to whether the low beam lights, the high beam lights, the daytime running lights, and the turn signal lights are respectively turned on or turned off, and threshold values of the output current, the output voltage, the input current, and the peak current may be set to be different from each other. Thus, in addition to protecting the LED elements included in the first to fourth LED arrays  512  to  518  by setting the voltage and the current of the DC/DC converter  522 , the current regulator  524 , and the like, differently with respect to each other for each separate operating condition, operating efficiency of the first to fourth LED arrays  512  to  518  may be increased. Referring to Table 1, the operating efficiency may be maintained in a constant state of 80% in a variety of operating conditions. 
     The functions of overcurrent protection, overvoltage protection, undervoltage lock out, overvoltage lock out, and the like, may be implemented by measuring actual values of various parameters such as input/output current, input/output voltage, peak current, and the like, and controlling the LED driving device  500  based on such values by the control module  530 . The functions of overcurrent protection, overvoltage protection, undervoltage lock out, overvoltage lock out, and the like, may be implemented using software running in the control module  530 . 
     In a case of implementing the over-current protection function using hardware in the control module  530 , an over-current threshold value may be set when the voltage V BAT  of the input power  580  changes within a range of 9 V to 16V, based on a minimum voltage of 9V. Therefore, even in a case in which the voltage V BAT  of the input power  580  increases to 16V, the same over-current threshold value may be applied. However, according to an exemplary embodiment of the present inventive concept, a threshold current value to be applied to the overcurrent protection may be actively set according to the voltage V BAT  of input power  580 . The threshold current value to be applied to the overcurrent protection may be determined by the software running on the control module  530 . 
     In a case of implementing the over-voltage protection function with hardware, a threshold voltage value for the over-voltage protection may be set according to a minimum value and a maximum value of the forward voltage of each LED element. For example, in a case in which the forward voltage of each LED element is set to 2.75V at least and 3.75V at most, and an LED array includes 15 series-connected LED elements, the threshold voltage value for the overvoltage protection may be set to a maximum forward voltage of 56.25V. Thus, in a case in which a portion of the LED elements short circuits, whether or not the LED elements have been short circuited may not be determined since the total forward voltage of the LED array is still measured to be less than 56.25V, and the characteristics of the LED elements having different bin data with respect to each other may not be sufficiently reflected. 
     According to an exemplary embodiment of the present inventive concept, a voltage value reflecting a respective LED element of the light source  510  characteristic may be set as a threshold voltage value for overvoltage protection by measuring the bin data related to the LED elements of the light source  510 . For example, when the minimum value and the maximum value of the forward voltage of each LED element of the light source  510  are 3.5V and 3.75V, respectively, in an LED array of the light source  510  having 15 LED elements connected to each other in series, the threshold voltage value for over-voltage protection may not be a specific value, but may be set within a range of 52.5V to 56.25V. Therefore, in a case in which a portion of the LED elements of the light source  510  are short circuited, whether or not the LED elements have been short circuited may be determined since the forward voltage of the entire LED array decreases to a level of 52.5V, the lower limit value of the range, or below. 
       FIG. 12  illustrates the configuration of an automobile to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 12 , LED driving devices  610  and  620  may be applied to the headlamps of an automobile  600 , and LED driving devices  630  and  640  may be applied to the tail lamps of the automobile  600 , according to an exemplary embodiment of the present inventive concept. Each of the LED driving devices  610 ,  620 ,  630 , and  640  may be connected to a vehicle body control module  650  to communicate therewith via communications protocols such as CAN. For example, the LED driving device  610  is connected to a vehicle body control module  650  using a communications protocol  615 , for example, CAN. The LED driving device  620  is connected to a vehicle body control module  650  using a communications protocol  625 , for example, CAN. The LED driving device  630  is connected to a vehicle body control module  650  using a communications protocol  635 , for example, CAN. The LED driving device  640  is connected to a vehicle body control module  650  using a communications protocol  645 , for example, CAN. An intelligent power switch (IPS) may be provided between each of the LED driving devices  610  to  640  and the body control module  650 . The IPS may be used to detect a disconnection, a short circuit, overcurrent, and the like, of the LED driving devices  610  to  640 . 
       FIG. 12  illustrates the LED driving devices  610  and  620  being provided on the left and right headlamps of the automobile  600 , respectively, and the LED driving devices  630  and  640  being provided on the left and right tail lamps of the automobile  600 , respectively. However, other configurations may be provided in addition to the configuration illustrated in  FIG. 12 . For example, one LED driving device may control the operation of the left and right headlamps of the automobile  600 , and another LED driving device may control the operation of the left and right tail lamps of the automobile  600 . In addition, a single LED driving device may control the left and right headlamps and the left and right tail lamps of the automobile  600 . 
     An LED driving device and an LED lighting device, in accordance with various exemplary embodiments of the present inventive concept, may be applied in various applications. Hereinafter, the various applications in which the LED driving device and the LED lighting device may be applied, according to various exemplary embodiments of the present inventive concept, will be described. 
       FIG. 13  is a perspective view illustrating a flat lighting device to which the LED driving device is applied, according to an exemplary embodiment of the present inventive concept. 
     Referring to  FIG. 13 , a flat lighting device  1000  may include a light source module  1010 , a power supply device  1020 , and a housing  1030 . In accordance with an exemplary embodiment of the present inventive concept, the light source module  1010  may include a light-emitting element array as a light source, and the power supply device  1020  may include a light-emitting driving unit. 
     The light source module  1010  may include a light-emitting element array, and may be formed to have an overall planar shape. In accordance with an exemplary embodiment of the present inventive concept, the light-emitting element array may include light-emitting elements and a controller storing driving information of the light-emitting elements. 
     The power supply device  1020  may be configured to supply power to the light source module  1010 . The housing  1030  may have a receiving space so that the light source module  1010  and the power supply device  1020  may be received therein, and may have a hexahedral shape of which one side is open, but is not limited thereto. The light source module  1010  may be disposed to emit light from an open side of the housing  1030 . 
     An LED driving device, according to an exemplary embodiment of the present inventive concept, may be applied to the power supply device  1020 . When a plurality of light source modules  1010  include LED arrays having different characteristics with respect to each other, the plurality of light source modules  1010  may be actively controlled and integrally protected, and power efficiency may be increased by applying the LED driving device to the power supply device  1020 , according to an exemplary embodiment of the present inventive concept. 
       FIG. 14  is an exploded perspective view illustrating a bulb-type lamp as a lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept. 
     A lighting device  1100  may include a socket  1110 , a power unit  1120 , a heat radiating unit  1130 , a light source module  1140 , and an optical unit  1150 . In accordance with an exemplary embodiment of the present inventive concept, the light source module  1140  may include a light-emitting element array, and the power unit  1120  may include a light-emitting element driving unit. 
     The socket  1110  may be configured to replace an existing lighting device. Power supplied to the lighting device  1100  may be applied through the socket  1110 . As illustrated in  FIG. 14 , the power unit  1120  may include a first power unit  1121  and a second power unit  1122 . The heat radiating unit  1130  may include an internal heat radiating unit  1131  and an external heat radiating unit  1132 . The internal heat radiating unit  1131  may be connected directly to the light source module  1140  and/or the power unit  1120 , through which heat may transfer to the external heat radiating unit  1132 . The optical unit  1150  may include an internal optical unit and an external optical unit, and may be configured to distribute light emitted from the light source module  1140  evenly. 
     The light source module  1140  may emit light to the optical unit  1150  by receiving power from the power unit  1120 . The light source module  1140  may include at least one light-emitting element  1141 , a circuit board  1142 , and a controller  1143 , and the controller  1143  may be capable of storing driving information of the light-emitting elements  1141 . 
     The LED driving device, according to an exemplary embodiment of the present inventive concept, may be provided as a controller  1143  and a power unit  1120 . For example, a DC/DC converter, a current regulator, or the like, according to an exemplary embodiment of the present inventive concept, may be included within the power unit  1120  supplying driving power to the light-emitting elements  1141 , and the controller  1143  may be provided as an MCU according to an exemplary embodiment of the present inventive concept. When at least a portion of a plurality of light-emitting elements  1141  included in the light source module  1140  are connected to each other in series to form two or more LED arrays, the lighting device  1100  may be efficiently controlled by applying thereto the LED driving device according to an exemplary embodiment of the present inventive concept thereto. 
       FIG. 15  is an exploded perspective view schematically illustrating a bar-type lamp as a lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept. 
     A lighting device  1200  may include a heat-radiating member  1210 , a cover  1220 , a light source module  1230 , a first socket  1240 , and a second socket  1250 . A plurality of heat-radiating fins  1211  and  1212  may be formed on the internal and/or external surfaces of the heat-radiating member  1210  in a corrugated form, and the plurality of heat-radiating fins  1211  and  1212  may be designed to have various shapes and spacings. A protruded supporting fixture  1213  may be formed on the inside of the heat-radiating member  1210 . The light source module  1230  may be fixed to the supporting fixture  1213 . The locking projections  1214  may be formed on both sides of the heat-radiating member  1210  opposing each other. 
     A locking groove  1221  is formed in the cover  1220 , and the locking projections  1214  of the heat-radiating member  1210  may be coupled to the locking groove  1221  in a hook coupling structure. The locations in which the locking groove  1221  and the locking projections  1214  are formed may be interchangeable with each other. 
     The light source module  1230  may include a light-emitting element array. The light source module  1230  may include a printed circuit board  1231 , a light source  1232 , and a controller  1233 . As described above, the controller  1233  may store driving information of the light source  1232 . Circuit wirings for operating the light source  1232  may be formed in the printed circuit board  1231 . In addition, the light source module  1230  may include configuration elements for operating the light source  1232 . 
     The first and second sockets  1240  and  1250 , as a pair of sockets, have a structure in which they are coupled to both ends of a cylindrical cover unit of the heat-radiating member  1210  and the cover  1220 . For example, the first socket  1240  may include an electrode terminal  1241  and a power device  1242 , and a dummy terminal  1251  may be disposed on the second socket  1250 . In addition, an optical sensor and/or a communications module may be provided in the first socket  1240  or the second socket  1250 . For example, an optical sensor and/or a communications module may be provided in the second socket  1250  on which the dummy terminal  1251  is provided. As another example, an optical sensor and/or a communications module may be provided in the first socket  1240  on which the electrode terminal  1241  is disposed. 
     An LED driving device, according to an exemplary embodiment of the present inventive concept, may be provided as the power device  1242  and the controller  1233 . Similar to an exemplary embodiment of the present inventive concept with reference to  FIG. 14 , a DC/DC converter and a current regulator may be included in the power device  1242 , and the controller  1233  may include an MCU, according to an exemplary embodiment of the present inventive concept. When a plurality of light-emitting element arrays connected to each other in parallel are included in the light source module  1230 , respective light-emitting element arrays may be actively controlled using the LED driving device, according to an exemplary embodiment of the present inventive concept. 
       FIG. 16  is an exploded perspective view schematically illustrating a lamp including a communications module as a lighting device to which an LED driving device is applied, according to an exemplary embodiment of the present inventive concept. 
     A lighting device  1300 , according to an exemplary embodiment of the present inventive concept, and the lighting device  1100  of  FIG. 14  may have a difference in that a reflecting plate  1310  is provided on an upper portion of a light source module  1340 , and the reflecting plate  1310  may reduce glare by allowing light emitted from a light source to be evenly diffused to the sides and the rear of the lighting device  1300 . 
     A communications module  1320  may be mounted on an upper portion of the reflecting plate  1310 , and home-network communications may be implemented via the communications module  1320 . For example, the communications module  1320  may be a wireless communications module using ZIGBEE, WI-FI or LI-FI, and may control switching on/off operations, brightness, and the like, of lighting devices installed in and around the home via a smartphone or wireless controller. In addition, electronic products such as TVs, refrigerators, air conditioners, door locks, automobiles, vehicle systems, and the like, may be controlled with the use of a LI-FI communications module using visible light wavelengths from lighting devices installed in and around the home. 
     The reflecting plate  1310  and the communications module  1320  may be covered by a cover portion  1330 . A socket  1370  may be configured to replace an existing lighting device. Power supplied to the lighting device  1300  may be applied through the socket  1370 . As illustrated, a power unit  1360  may include a first power unit  1361  and a second power unit  1362  assembled together. A heat-radiating unit  1350  may include an internal heat-radiating unit  1351  and an external heat-radiating unit  1352 . The internal heat-radiating unit  1351  may be connected directly to the light source module  1340  and/or the power unit  1360 , through which heat may transfer to the external heat-radiating unit  1352 . Similar to an exemplary embodiment of the present inventive concept with reference to  FIG. 14 , an LED driving device according to an exemplary embodiment of the present inventive concept may also be applied to the lighting device  1300  shown in  FIG. 16 . 
       FIG. 17  is a schematic view illustrating an indoor lighting control network system, according to an exemplary embodiment of the present inventive concept. 
     A network system  2000 , according to an exemplary embodiment of the present inventive concept, may be a smart lighting-network system fused with lighting technology using light-emitting elements such as LEDs, Internet of Things (IoT) technology, wireless communications technology, and the like. The network system  2000  may be implemented using a range of lighting devices and wired and wireless communications devices, and may be implemented by software for control and maintenance of sensors, controllers, communications means, network, and the like. 
     The network system  2000  may be applied not only to closed spaces within buildings such as homes or offices, but also to open spaces such as parks, streets, and the like. The network system  2000  may be implemented based on IoT environment to acquire and/or process and provide a range of information to users. In this case, an LED lamp  2200  included in the network system  2000  may not only control light of the LED lamp  2200  itself by receiving information of the surrounding environment from a gateway  2100 , but also perform operations such as status verification, control, and the like, of other devices  2300  to  2800  included in the IoT environment based on visible light communications, and the like, of the LED lamp  2200 . 
     Referring to  FIG. 17 , the network system  2000  may include the gateway  2100  for processing data transmitted and received in accordance with different communications protocols with respect to each other, the LED lamp  2200  connected to the gateway  2100  to allow communications and including LED light-emitting elements, and the plurality of devices  2300  to  2800  connected to the gateway  2100  to allow communications therewith according to various wireless communications methods. To implement the network system  2000  based on the IoT environment, the respective devices  2300  to  2800 , including the LED lamp  2200 , may include at least one communications module. In an exemplary embodiment of the present inventive concept, the LED lamp  2200  is connected to the gateway  2100  to allow communications by a wireless communications protocol such as WI-FI, ZIGBEE, LI-FI, and the like, and may have at least one communications module for a lamp  2210 . 
     As described above, the network system  2000  may be applied not only to closed spaces such as homes or offices, but also to open spaces such as parks or streets. In a case in which the network system  2000  is applied to a home, the plurality of devices  2300  to  2800  included in the network system  2000 , connected to the gateway  2100  to allow communications  2100  based on the IoT technology, may include home appliances  2300 , digital door locks  2400 , garage door locks  2500 , light switches installed on walls  2600 , routers  2700  for access to a wireless communications network, and mobile devices  2800  such as smart phones, tablets, laptop computers, and the like. The home appliances  2300  may include a television  2310  and a refrigerator  2320 . 
     In the network system  2000 , the LED lamp  2200  may verify operating statuses of the various devices  2300  to  2800  using a wireless communications network installed in the home (e.g., ZIGBEE, WI-FI, LI-FI, and the like), or automatically adjust the intensity of illumination of the LED lamp  2200  itself according to the surrounding environment and/or conditions. In addition, the devices  2300  to  2800  included in the network system  2000  may also be controlled using LI-FI communications using visible light emitted from the LED lamp  2200 . 
     The LED lamp  2200  may automatically adjust the intensity of light of the LED lamp  2200  based on surrounding environment information transferred from the gateway  2100  through the communications module for a lamp  2220 , or information of surrounding environment collected from a sensor mounted on the LED lamp  2200 . For example, a brightness of the LED lamp  2200  may be automatically adjusted according to a brightness of a screen or the type of program being broadcast on the television  2310 . The LED lamp  2200  may receive operation information of the television  2310  from the communications module for a lamp  2220  connected to the gateway  2100 . The communications module for a lamp  2220  may be integrated as a module with the sensor and/or a controller included in the LED lamp  2200 . 
     In a case in which the program being aired on TV is a documentary, the lighting may be lowered to a color temperature of 12000K or less, for example, 5000K, and the color may be adjusted, depending on a pre-set setting value, to create a cozy atmosphere. In a case in which the program is a comedy, the color temperature may be increased to 5000K or more according to a luminance setting value, and the network system may be configured to be adjusted to white light in a blue color series. 
     After a preset period of time passes in a case in which the digital door lock  2400  is locked in a state where no one is at home, all of the LED lamps  2200  that are turned on may be turned off to prevent electricity wastage. Alternatively, in a case in which a security mode is set via the mobile device  2800 , or the like, and the digital door lock  2400  is locked in a state where no one is at home, the LED lamp  2200  may be kept turned on. 
     The operation of the LED lamp  2200  may be controlled according to the surrounding environment information collected from a range of sensors connected to the network system  2000 . For example, when the network system  2000  is implemented in a building, lighting may be turned on or off by combining the lighting, the position of the sensor, and the communications module in a building, and by collecting location information of people in the building, or the collected information may be provided in real-time to enable facility management or efficient use of idle space. Since general lighting devices such as the LED lamps  2200  may be disposed in a majority of areas in each floor of a building, a range of information regarding the building may be collected via the sensors provided integrally with the LED lamps  2200 , which may be used in facility management and use of idle space. 
     In addition, by combining the LED lamp  2200  with an image sensor, a storage device, the communications module for a lamp  2220 , and the like, the LED lamp  2200  may be utilized as a device for maintaining security in a building or detecting and responding to emergencies. For example, in a case that a smoke detector or a temperature sensor, or the like, is provided in the LED lamp  2200 , damage may be reduced by detection of fire, or the like. In addition, energy may be saved and a comfortable lighting atmosphere may be provided by controlling the brightness of the lighting in consideration of external weather conditions or sunlight. 
     An LED driving device, according to an exemplary embodiment of the present inventive concept, may be applied to the LED lamp  2200 . When a plurality of LED lamps  2200  are provided in the network system  2000 , the plurality of LED lamps  2200  may be integrally controlled by a single LED driving device. Further, the LED lamps  2200  may have different light-emitting characteristics and may be controlled actively and integrally, and power efficiency may be increased by setting and applying protection parameters adapted to the characteristics of each LED lamp  2200 . 
     As described above, the network system  2000  may be applied not only to closed spaces such as homes, offices, or buildings but also to open spaces such as parks or streets. In a case of applying the network system  2000  to a large open space, it may be difficult to implement the network system  2000  due to factors such as a distance limit of wireless communications and communications interference due to various obstacles. The network system  2000  may be implemented in an open space as described above by mounting a sensor, a communications module, and the like, to respective lighting fixtures, and by using the respective lighting fixtures as information acquisition units and communications intermediate units, which will be described below with reference to  FIG. 18 . 
       FIG. 18  illustrates a network system  3000  applied to an open space, according to an exemplary embodiment of the present inventive concept. Referring to  FIG. 18 , the network system  3000 , according to an exemplary embodiment of the present inventive concept, may include a communications connection device  3100 , a plurality of lighting fixtures  3200  and  3300  connected to the communications connection device  3100  at predetermined distances to allow communications, a server  3400 , a computer  3500  for managing the server  3400 , a communications base station  3600 , a communications network  3700  for connecting the above communications devices, and a mobile device  3800 . 
     The plurality of lighting fixtures  3200  and  3300  installed in external open spaces, such as a street or a park, may respectively include smart engines  3210  and  3310 . The smart engines  3210  and  3310  may include a sensor collecting information of a surrounding environment, a communications module, and the like, in addition to light-emitting elements, and a driver for driving the light-emitting elements. The smart engines  3210  and  3310  may communicate with other devices nearby by the communications module according to a communications protocol such as WI-FI, ZIGBEE, AND LI-FI. 
     For example, a single smart engine  3210  may be connected to another smart engine  3310  to enable communications therewith. In this case, a WI-FI extension technique (e.g., WI-FI mesh) may be applied to communications between the smart engines  3210  and  3310 . At least one smart engine  3210  may be connected to the communications connection device  3100  connected to the communications network  3700  by a wired and/or wireless communications. To increase communications efficiency, a plurality of smart engines  3210  and  3310  may be coupled together as a single group and connected to a single communications connection device  3100 . 
     The communications connection device  3100  may be an access point (AP) capable of allowing for wired and/or wireless communications, and may allow for intermediate the communications between the communications network  3700  and other devices. The communications connection device  3100  may be connected to the communications network  3700  in a wired or wireless manners, and for example, the communications connection device may be stored mechanically inside at least one of the lighting fixtures  3200  and  3300 . 
     The communications connection device  3100  may be connected to the mobile device  3800  via a communications protocol such as WI-FI or the like. A user of the mobile device  3800  may receive information of a surrounding environment collected by the plurality of the smart engines  3210  and  3310  via the communications connection device  3100  connected to the smart engine  3210  of the lighting fixture  3200 . The information of the surrounding environment may include surrounding traffic information, weather information, and the like. The mobile device  3800  may be connected to the communications network  3700  in a wireless cellular communication method such as a third generation of mobile telecommunications technology (3G) or a fourth generation of mobile telecommunications technology (4G) via the communications base station  3600 . 
     The server  3400  connected to the communications network  3700  may receive information collected by the smart engines  3210  and  3310  mounted in the respective lighting fixtures  3200  and  3300 , and simultaneously, may monitor an operation status, and the like, of the respective lighting fixtures  3200  and  3300 . To manage the respective lighting fixtures  3200  and  3300  based on the monitoring result of the operation status of the respective lighting fixtures  3200  and  3300 , the server  3400  may be connected to the computer  3500  providing a management system. The computer  3500  may run a software, and the like, capable of monitoring and managing the operation status of the respective lighting fixtures  3200  and  3300  using the smart engines  3210  and  3310 . 
       FIG. 19  is a block diagram illustrating an operation of the smart engine  3210  of the lighting fixture  3200  of  FIG. 18  and the mobile device  3800  of  FIG. 18  by visible light wireless communications. A range of communications methods may be applied to transfer the information collected by the smart engines  3210  and  3310  to a user&#39;s mobile device  3800 . Referring to  FIG. 19 , the information collected by the smart engine  3210  may be transferred to the mobile device  3800  via the communications connection device  3100  which is connected to the smart engine  3210  and to the mobile device  3800 . In addition, the smart engine  3210  may be connected directly to the mobile device  3800  to allow direct communications. In addition, the information collected by the smart engine  3310  may be transferred to the mobile device  3800  via the communications connection device  3100  which is connected to the smart engine  3310  and to the mobile device  3800 . Further, the smart engine  3310  may be connected directly to the mobile device  3800  to allow direct communications. The smart engines  3210  and  3310  and the mobile device  3800  may communicate directly with each other by a visible light wireless communications, for example, LI-FI, which will be described below with reference to  FIG. 19 . 
     Referring to  FIG. 19 , the smart engine  3210  may include a signal processing unit  3211 , a control unit  3212 , an LED driver  3213 , a light source unit  3214 , a sensor  3215 , and the like. The mobile device  3800  connected to the smart engine  3210  by visible light wireless communications may include a control unit  3801 , a light receiving unit  3802 , a signal processing unit  3803 , a memory  3804 , an input/output unit  3805 , and the like. 
     The visible light wireless communications LI-FI technology may be a wireless communications technology for transmitting information wirelessly using light in a visible wavelength band recognized by the human eye. Such a visible light wireless communications technology may be distinguished from the existing wired optical communications technology and infrared wireless communications in that light in the visible light wavelength band is light that includes a specific visible light frequency emitted from the lighting fixtures or the lighting devices described above. Also, the visible light wireless communications technology may be distinguished from wired optical communications technology in that the communications environment of the visible light wireless communications technology is wireless. Further, the visible light wireless communications technology may be used freely, without being regulated by guidelines. Thus the visible light wireless communications technology may be convenient and the physical security thereof may be excellent. In the visible light wireless communications technology, the communications link may be checked by the user visually. The visible light wireless communications may emit visible light and may transmitting information wirelessly. 
     Referring to  FIG. 19 , the signal processing unit  3211  of the smart engine  3210  may process data to be transmitted and received by the visible light wireless communications. In an exemplary embodiment of the present inventive concept, the signal processing unit  3211  may acquire and process information collected by the sensor  3215  and may transmit the processed information to the control unit  3212 . The control unit  3212  may control operations of the signal processing unit  3211 , the LED driver  3213 , and the like. The control unit  3212  may control the operation of the LED driver  3213  based on the processed information transmitted by the signal processing unit  3211 . The LED driver  3213  may transmit data to the mobile device  3800  by allowing the light source unit  3214  to emit light in response to a control signal transmitted by the control unit  3212 . 
     The mobile device  3800  may include the control unit  3801 , the memory  3804  storing data, the input/output unit  3805  including a display, a touch screen, an audio output unit, and the like, the signal processing unit  3803 , and the light receiving unit  3802  for recognizing visible light containing data. The light receiving unit  3802  may detect visible light and convert the visible light into an electrical signal, and the signal processing unit  3803  may decode the data contained in the electrical signal converted by the light receiving unit  3802 . The control unit  3801  may store the data decoded by the signal processing unit  3803  in the memory  3804 , or output the decoded data via the input/output unit  3805  to be recognized by the user. 
     In exemplary embodiments of the present inventive concept described with reference to  FIGS. 18 and 19 , the smart engine  3210  may include an LED driving device according to an exemplary embodiment of the present inventive concept. Referring to  FIG. 19 , the control unit  3212  may correspond to an MCU in an LED driving device according to an exemplary embodiment of the present inventive concept, and the LED driver  3213  may correspond to a power supply module. A single MCU may not only actively control and protect the light source unit  3214 , but may also provide a visible light communications function. 
     As described above, according to various exemplary embodiments of the present inventive concept, the operation of the power supply module may be controlled based on operating data related to the power supply module supplying driving power to a plurality of LED elements, as well as characteristic data related to the plurality of LED elements. Since the control module controlling the operation of the power supply module may be provided as a programmable MCU, by changing the operation of the control module by running a software program suitable for loading conditions, operating conditions, and surrounding conditions, LEDs may be actively driven and protected, and circuit configuration may be simplified. 
     While the inventive concept has been particularly shown and described with reference to exemplary embodiments thereof, it will be apparent to those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.