Patent Publication Number: US-11380247-B2

Title: Display apparatus and method of controlling the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is based on and claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2019-0158672, filed on Dec. 3, 2019 in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Field 
     The disclosure relates to a display apparatus including a plurality of light emitting diodes (LEDs) and a method of controlling the same. 
     2. Description of Related Art 
     A display apparatus may include a non-emissive display panel such as a liquid crystal display (LCD) and an emissive display panel that generates light corresponding to a data signal. In particular, research on a light emitting diode (LED), which is an inorganic light emitting element, is being actively conducted to implement the emissive display panel. 
     The LED is an element that converts electrical signals into light forms such as infrared and visible rays using the characteristics of compound semiconductors. The LED is not only used in home appliances, remote controls, electronic boards, and various automation devices, but also is increasingly used in small handheld electronic devices and large display apparatuses. 
     In recent years, research has been conducted on a modular display in which multiple LED modules including a certain number of LEDs are combined into a single device to form a single screen. The modular display is implemented in a collective installation method of digital information display (DID) panels, and has an advantage of not being restricted in implementing a resolution desired by a consumer. 
     The modular display supplies power and data so that the LEDs provided in each module emit light. In the conventional modular display, a main board or a switching mode power supply (SMPS) for supplying power and data for each module is separately provided. 
     SUMMARY 
     Provided are a display apparatus capable of improving power efficiency and operating efficiency of a driving integrated circuit (IC), and controlling a plurality of LED modules by one main board controlling at least two LED modules, and a method of controlling the display apparatus. 
     Additional aspects of the disclosure will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the disclosure. 
     In accordance with an aspect of the disclosure, a display apparatus includes a first light emitting diode (LED) module including a first driving assembly; a second LED module including a second driving assembly; a connector configured to connect the first driving assembly to the second driving assembly; and a processor connected to the first driving assembly, wherein the processor is configured to transmit image data and a control signal to the first driving assembly, and wherein the first driving assembly is configured to operate based on the image data, and to transmit the image data and the control signal to the second driving assembly through the connector. 
     The second driving assembly may be configured to operate based on the image data received through the connector, and to transmit a feedback signal based on the control signal to the processor through the connector. 
     The control signal may include a signal for selecting the second LED module, and the processor may be configured to transmit the control signal for selecting the second LED module through the connector. 
     Each of the first driving assembly and the second driving assembly may include a respective memory configured to store respective calibration data for a plurality of LEDs. 
     The second driving assembly may be configured to transmit the calibration data in a feedback signal based on the control signal. 
     The second driving assembly may include a first connector configured to be connected to the first driving assembly through a first cable; and a second connector configured to be connected to a third driving assembly through a second cable. 
     The second driving assembly may be configured to transmit a feedback signal based on the control signal to the processor through the connector, and the second driving assembly may be configured to change the feedback signal based on a connection state of the second connector and the second cable. 
     The first connector may include a first plurality of pins and the second connector may include a second plurality of pins, wherein at least one of the first plurality of pins is in electrical contact with at least one of the second plurality of pins; and the processor may be configured to transmit the control signal based on at least three or more pins among the first plurality of pins and the second plurality of pins. 
     The second connector may include at least one pin connected to a ground. 
     The first driving assembly and the second driving assembly may each include a respective plurality of driving integrated circuits (ICs), each of the plurality of driving ICs being configured to control a predetermined number of respective LEDs; and the plurality of driving ICs may be configured to operate based on the image data. 
     Each of the first LED module and the second LED module may include a respective switching mode power supply (SMPS) configured to supply power to the first driving assembly and the second driving assembly, respectively. 
     In accordance with an aspect of the disclosure, a method of controlling a display apparatus, the display apparatus including a first light emitting diode (LED) module including a first driving assembly, a second LED module including a second driving assembly, a cable configured to connect the first driving assembly to the second driving assembly, and a processor connected to the first driving assembly, the method includes transmitting, by the processor, image data and a control signal to the first driving assembly; transmitting, by the first driving assembly, the image data and the control signal to the second driving assembly through the cable; and transmitting, by the second driving assembly, a feedback signal based on the control signal to the first driving assembly through the cable. 
     The control signal may include a signal for selecting the second driving assembly. 
     Each of the first driving assembly and the second driving assembly may include a respective memory configured to store calibration data for a plurality of LEDs; and the transmitting by the second driving assembly may include transmitting the calibration data in the feedback signal based on the control signal. 
     The second driving assembly may include a first connector configured to be connected to the cable; and a second connector configured to be connected to a third driving assembly through an additional cable, and the transmitting by the first driving assembly may include transmitting the image data and the control signal through the first connector. 
     The transmitting by the second driving assembly may include changing the control signal based on a connection state of the second connector. 
     The cable may include a plurality of pins in electrical contact with the first connector of the second driving assembly; and the transmitting by the processor may include transmitting the control signal to the third driving assembly using at least three pins among the plurality of pins. 
     The second connector may have at least one pin connected to a ground, and the transmitting by the first driving assembly may include transmitting a ground signal through the at least one pin to the second driving assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is an external view illustrating a display system according to an embodiment; 
         FIG. 2  is a view illustrating a schematic arrangement and signal flows in a display system according to an embodiment; 
         FIG. 3  is a control block diagram of a display apparatus according to an embodiment; 
         FIG. 4  is an exploded view of a main configuration of a display apparatus; 
         FIG. 5  is a view schematically illustrating a driving assembly of two adjacent LED modules; 
         FIG. 6  is a view for describing a driving connection state included in three LED modules according to an embodiment; 
         FIGS. 7 to 9  are views for describing an embodiment of a first control signal for selecting an LED module; 
         FIGS. 10, 11, and 12  are views of a pin map for describing a second control signal. 
         FIG. 13  is a flowchart illustrating operations of a display apparatus according to an embodiment; and 
         FIG. 14  is a flowchart illustrating operations of a display apparatus according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Like reference numerals refer to like elements throughout the specification. Not all elements of embodiments of the disclosure will be described, and the description of what are commonly known in the art or what overlap each other in example embodiments will be omitted. The terms as used throughout the specification, such as “˜part,” “˜module,” “˜member,” “˜block,” etc., may be implemented in software and/or hardware, and a plurality of “˜parts,” “˜modules,” “˜members,” or “˜blocks” may be implemented in a single element, or a single “˜part,” “˜module,” “˜member,” or “˜block” may include a plurality of elements. 
     It will be further understood that the term “connect” and its derivatives refer both to direct and indirect connection, and the indirect connection includes a connection over a wireless communication network. 
     The terms “include (or including)” and “comprise (or comprising)” are inclusive or open-ended and do not exclude additional, unrecited elements or method steps, unless otherwise mentioned. It will be further understood that the term “contact” and its derivatives refer both to when a member is in contact with another member and when another member exists between the two members. 
     Further, when it is stated that a layer is “on” another layer or substrate, the layer may be directly on another layer or substrate or a third layer may be disposed therebetween. 
     It will be understood that, although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. 
     It is to be understood that the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. 
     Reference numerals used for method steps are merely used for convenience of explanation, but not to limit an order of the steps. Thus, unless the context clearly dictates otherwise, the written order may be practiced otherwise. 
     Hereinafter, an operation principle and embodiments of the disclosure will be described with reference to accompanying drawings. 
       FIG. 1  is an external view illustrating a display system according to an embodiment, and  FIG. 2  is a view illustrating a schematic arrangement and signal flows in a display system according to an embodiment. 
     Referring to  FIGS. 1 and 2 , a display system  1  may include a display apparatus  10  that visually presents an image and an image reproducing apparatus  20  that provides image data to the display apparatus  10 . 
     The display system  1  may be used as a big screen in theaters, as a general display apparatus, such as in televisions (TVs) and monitors, or for a large billboard. The display system  1  may be installed outdoors, e.g., on the rooftop of a building or at a bus stop. However, the display system  1  may be installed indoors, e.g., at subway stations, shopping malls, theaters, offices, stores, etc. 
     The display apparatus  10  may include a plurality of light emitting diode (LED) modules  100 . Each LED module  100  may include LEDs to provide a particular resolution. When a relatively large pitch size is provided between the LEDs, the display apparatus  10  may be used for an information transferring device, such as a large billboard. On the contrary, when a relatively small pitch size, such as on the scale of micrometers (μm), is provided between the LEDs, the display apparatus  10  may be used for a high resolution screen in a theater as well as TVs. 
     The plurality of LED modules  100  may be arranged in rows and columns. In other words, the LED modules  100  may be arranged in the form of a matrix, for example, in a 4×3 matrix as shown in  FIG. 1 . However, the display apparatus  1  does not necessarily include only 12 LED modules  100 , and it is sufficient if two or more LED modules are connected in series. 
     The plurality of LED modules  100  arranged in a matrix may be integrated into a single screen S. The integrated LED modules  100  may be controlled to display an image. 
     Each LED in the plurality of LED modules  100  may correspond to a unit pixel P, and an image may be formed by a combination of light emitted from the plurality of pixels P. For example, the plurality of pixels P may emit light with various brightnesses and colors, and the light emitted by the plurality of pixels P may be combined into an image that may be perceived by a viewer. 
     The screen S may include a variable number of LEDs corresponding to various resolutions. For example, to have 4K resolution according to Digital Cinema Initiatives (DCI), the screen S may include 4096×2160 LEDs. In another example, to have 4K ultra high definition (UHD) resolution according to the International Telecommunication Union (ITU), the screen S may include 3840×2160 LEDs. Particularly, when each unit pixel P of the screen S having the 4K resolution includes a red LED, a blue LED, and a green LED, the number of LEDs corresponding to the 4K resolution may be 4096×2160×3 or 3840×2160×3. When each LED corresponding to the unit pixel P is a single LED chip, which is an encapsulation of red, blue, and green LEDs, the number of LEDs corresponding to the 4K resolution may be 4096×2160 or 3840×2160. 
     The image reproducing apparatus  20  may store content, such as a video, or may receive the content from an external content source (e.g., a video streaming service server). For example, the image reproducing apparatus  20  may store a file of content data in a storage, or receive content data from the external content source in real time. 
     The image reproducing apparatus  20  may decode the stored or received content data into image frame data (hereinafter, image data). For example, a broadcast signal or content data may be received or stored in a compressed format according to various video compression standards, such as Moving Picture Experts Group (MPEG), High Efficiency Video Coding (HEVC), etc. The image reproducing apparatus  20  may restore the image data representing each image frame from the compressed content data. 
     The image reproducing apparatus  20  may transmit the restored image data to the display apparatus  10 . 
     Referring to  FIG. 2 , there may be image data lines, such as image data line L 1 , between the image reproducing apparatus  20  and the plurality of LED modules  101 ,  102 , and  103 , and the image reproducing apparatus  20  may transmit the image data to the plurality of LED modules  101 ,  102 , and  103  through the image data lines.  FIG. 2  illustrates a single image data line L 1 . 
     Upon reception of the image data, the plurality of LED modules  101 ,  102 , and  103  may each display a portion of an image to be displayed on the entire screen S. Particularly, each of the plurality of LED modules  101 ,  102 , and  103  may occupy a certain area on the screen S and output a portion of the entire image corresponding to where the LED module is arranged. 
     The image data may be divided into frames, and the display apparatus  1  performs timing control so that a plurality of LED modules  101 ,  102 , and  103  divide and display a single frame. A detailed description of this will be described later with reference to the following drawings. 
       FIG. 3  is a control block diagram of a display apparatus according to an embodiment. 
     Referring to  FIG. 3 , the display apparatus  10  may include a user input device  110  for receiving a user input from the user, a content receiver  120  for receiving a video signal and/or an audio signal (or collectively, an image signal) from content sources, an image display  130  for displaying an image, a communication interface  140  for communicating with external devices, a sound output device  150  for outputting sound, a data storage  160  for storing various programs and data, and a controller  170  for controlling operations of the display apparatus  10 . 
     The user input device  110  may include an input button  111  for receiving a user input, and a signal receiver  112  for receiving a remote control signal from a remote controller. For example, the user input device  110  may include a power button for soft turn-on (operation start) or soft turn-off (operation stop) of the display apparatus  10 , a sound control button to control sound volume output by the display apparatus  10 , a source selection button to select a content source, etc. 
     The input button  111  may receive a user input, generate an electric signal corresponding to the user input, and transmit the electric signal to the controller  170 . The input button  111  may be implemented with various input devices such as a push switch, a touch switch, a dial, a slide switch, a toggle switch, etc. 
     The remote controller may be provided separately from the display apparatus  10 , and may receive a user input and transmit a radio signal corresponding to the user input to the display apparatus  10 . The signal receiver  112  may receive a radio signal corresponding to a user input from the remote controller, generate an electric signal corresponding to the user input, and transmit the electric signal to the controller  170 . 
     The content receiver  120  may include receiving terminal  121  and a tuner  122  for receiving an image signal including a video signal and/or an audio signal from the content sources. According to one or more embodiments, the content receiver  120  may include a plurality of receiving terminals  121 . 
     The receiving terminals  121  may receive a video signal and an audio signal from the content sources through a cable. For example, the receiving terminals  121  may include a component (YPbPr/RGB) terminal, a composite video blacking and sync (CVBS) terminal, an audio terminal, a high definition multimedia interface (HDMI) terminal, a universal serial bus (USB) terminal, etc. 
     The tuner  122  may receive broadcast signals through an antenna or a cable, and extract a broadcast signal corresponding to a channel selected by the user among the received broadcast signals. For example, the tuner  122  may pass a broadcast signal having a frequency corresponding to a channel selected by the user among the plurality of broadcast signals received through the antenna or the cable, and block other broadcast signals having different frequencies. 
     As such, the content receiver  120  may receive an image signal from the content sources through the receiving terminal  121  and/or the tuner  122 , and transmit the image signal to the controller  170 . The controller  170  may analyze/process the image signal and then convert the image signal to image data, as will be described later. 
     The image display  130  may include a driving assembly  200  for converting image data to an analog signal, and the plurality of LEDs  300  driven by the driving assembly  200 . The image display  130  may include, for example, an LED module  100 . 
     As described above in  FIGS. 1 to 2 , the display apparatus  10  is divided into the plurality of LED modules  100 . Each LED module  100  may include the driving assembly  200  for driving the plurality of LEDs  300  provided in the LED module  100 . 
     The driving assembly  200  may include a preset number of driving ICs, for example, driving ICs  211  to  218  (see  FIG. 5 ) for driving 16*30 LEDs  300 . The driving assembly  200  includes the plurality of driving ICs  211  to  218 , and further includes various configurations, such as a power assembly for supplying power to the driving ICs  211  to  218 , connectors  220  and  230  for transmitting control signals and image data transmitted from the controller  170 . A detailed description thereof will be described later through other drawings. 
     The communication interface  140  may exchange data with external devices other than the display device  10 . For example, the communication interface  140  may exchange data with a user equipment or other electronic devices. 
     The wired communication interface  141  may access a wired communication network and communicate with an external device over the wired communication network. For example, the wired communication interface  141  may access a wired communication network through Ethernet, the IEEE 802.3 technology standard, or the like and receive data from external devices over the wired communication network. 
     The wireless communication interface  142  may communicate wirelessly with a base station or an access point (AP), and access the wired communication network via the base station or the AP. The wireless communication interface  142  may communicate with external devices connected to the wired communication network via the base station or the AP. For example, the wireless communication interface  142  may use Wi-Fi™, the IEEE 802.11 technology standard, or the like to communicate with an AP, or use code divisional multiple access (CDMA), wideband code division multiple access (WCDMA), Global Systems for Mobile communications (GSM), Long Term Evolution (LTE), WiBro, etc., to communicate with a base station. The wireless communication interface  142  may receive data from the external devices via the base station or the AP. 
     In addition, the wireless communication interface  142  may communicate directly with the external device, such as a UE. For example, the wireless communication interface  142  may use Wi-Fi™, Bluetooth™, which is the IEEE 802.15.1 technology standard, ZigBee™, which is the IEEE 802.15.4 technology standard, etc., to wirelessly receive data directly from the external device. 
     The sound output device  150  may include a speaker  151  for outputting sound in an audible signal or sound waves. 
     The speaker  151  may convert an analog sound signal amplified by an amplifier to a sound or sound waves. For example, the speaker  151  may include a thin film that vibrates according to an electric sound signal, and the vibration of the thin film may generate sound waves. 
     The data storage  160  may include a storage medium for storing a program and data for controlling the operation of the display device  10 . The program may include a plurality of instructions containing a code made by a compiler or a code executable by an interpreter, which when executed by a processor of the display device, control the display to device to perform a particular function, and the data may be processed according to the plurality of instructions included in the program. 
     The storage medium  161  may store content data in a file format. For example, the storage medium  161  may store the content data in the form of “*.mpg”, “*.avi”, “*.asf”, or “*.mp4” file, and provide the content data to the controller  170  in response to a readout instruction from the controller  170 . 
     For example, the storage medium  161  may store an image signal input from the content receiver  120  and/or the communication interface  140 , and provide the stored image signal for the controller  170  to process image data. In another example, the storage medium  161  may receive and store the image data processed by the controller  170 . 
     The storage medium  161  may store the program and/or data electrically, magnetically, or optically. For example, the storage medium  161  may include a solid state drive (SSD), a hard disc drive (HDD), an optical disc drive (ODD), or the like. 
     The controller  170  may include one or more memories  172  for memorizing/storing a program/data, and one or more processors  171  for processing the data according to the program. The controller  170  may include hardware, such as the memory  172  and the processor  160 , and software, such as the program and/or data memorized/stored in the memory  171  and/or the data storage  160 . 
     The processor  171  may process the data stored in the memory  172  according to programs (or a series of programs). For example, the processor  171  may process the user input, the image data, the communication data, the stored data, etc., according to the program stored in the memory  172 . Furthermore, the processor  171  may generate a control signal to control at least one of the image display  130 , the communicator  140 , or the data storage  160  based on a result of processing the data. 
     Particularly, the processor  171  may perform data processing on the image signal and generates the control signal for driving the LED module  100 . In addition, the processor  171  may perform timing control so that each LED module  100  divides and displays the single frame. For each of the above-described operations, the number of processors  171  may be provided in a single or in plural. 
     In addition, the processor  171  may transmit the control signal and the image data to the driving assembly  200 . 
     Particularly, the image data transmitted by the processor  171  may be transmitted to the driving assembly  200 , and the plurality of driving ICs  211  to  218  provided in the driving assembly  200  may operate based on the image data. The plurality of driving ICs  211  to  218  may sequentially transmit image data and control signals through a cascade method. 
     The processor  171  may transmit a control signal for controlling the driving assembly  200 . According to the control signal, the driving assembly  200  may perform various operations other than displaying the image. 
     As an example, the processor  171  may transmit a control signal (hereinafter, referred to as a first control signal) for instructing the driving assembly  200  to transmit calibration data stored in the memory  172  of the driving assembly  200 . The driving assembly  200  may then transmit the calibration data stored in the memory  172  back to the processor  171  based on the first control signal, and this signal is referred to as a feedback signal. 
     As another example, the processor  171  may transmit a control signal (a second control signal) for selecting whether to transmit the image data to another driving assembly  200  connected through the cable  225  by the driving assembly  200  (see, e.g.,  FIG. 5 ). That is, the driving assembly  200  may select whether to transmit the image data to another driving assembly  200  connected by the cable  225  or to transmit the feedback signal to the processor  171  based on the second control signal. 
     A detailed description of this will be described later through other drawings. 
     The memory  172  may store a program and data for controlling the components included in the display device  10 . The memory  172  may include a non-volatile memory, such as a Read Only Memory (ROM), a flash memory, and/or the like, which may store data for a long period, and a volatile memory, such as a static random access memory (SRAM), a dynamic RAM (DRAM), or the like, which may temporarily store data. 
     The memory  172  may store calibration data. The calibration data may be derived as a result of an inspection performed in a production stage of the LED module  100 . Since the LEDs  300  have different characteristics even on the same wafer, the characteristics of RGB may be different for each production lot. Manufacturers may perform calibration so that the LED modules produced have the same product specifications. A characteristic value of the LED module  100  by calibration, that is, the calibration data may be stored in the memory  172 . 
     The memory  172  may be present in a chip integrally with the processor  171 , or may be provided in each of the plurality of driving assemblies  200 . Hereinafter, the memory provided in the driving assembly  200  will be described as another drawing. 
     The control block diagram of  FIG. 3  is illustrated to describe the function of each component, and does not necessarily show a position of each component. For example, the memory  172  may be provided as a flash memory in the driving assembly  200  that drives the LED module  100 . In addition, each LED module  100  may each include the memory  172  storing its own calibration data. 
       FIG. 4  is an exploded view of a main configuration of a display apparatus, and  FIG. 5  is a view schematically illustrating a driving assembly of two adjacent LED modules. 
     Referring to  FIG. 4 , the display apparatus  10  may include a cover glass  131 , the plurality of LED modules  100 , a frame  132  supporting the plurality of LED modules  100 , and a rear cover  133  covering a rear surface of the frame  132 . 
     As described above, the plurality of LED modules  100  may be provided in various M*N matrix in addition to the 4*3 matrix. 
     The cover glass  131  for protecting and supporting the LED module  100  may be attached to the front surface of the plurality of LED modules  100 . An optical film for improving optical performance may be provided between the cover glass  131  and the plurality of LED modules  100 . As the optical film, a circular polarizing film, a linear polarizing film, a retardation film, an AG/LR/AR/HC film, a Neutral Density (ND) film, etc., which are used to improve image quality in organic light emitting diodes (OLEDs) or liquid crystal displays (LCDs), may be used. 
     The plurality of LED modules  100  may be installed on the frame  132  through various known methods, such as magnetic force using a magnet or a mechanical fitting structure. 
     The rear cover  133  may form a rear surface of the display apparatus  1 . 
     The display apparatus  10  may include a driving circuit board for controlling the plurality of LED modules  100 . The display apparatus  10  may be provided with the driving assembly  200  (see, e.g.,  FIG. 5 ) to correspond to each LED module  100 . The driving assembly  200  may be provided on the rear surface of the LED module  100 . 
       FIG. 5  is a view schematically illustrating a driving assembly of two adjacent LED modules. 
     As described above in  FIGS. 1 and 2 , the display apparatus  10  may include the plurality of LED modules  100 . The plurality of LED modules  100  are manufactured to include the same configuration. Therefore, each LED module  100  may be connected to a different position, and for this purpose, each LED module  100  has the driving assembly  200  including the same configuration. 
     Referring to  FIGS. 5 and 6 , two adjacent LED modules among the plurality of LED modules  100 , for example, a first LED module  101  and a second LED module  102 , respectively, have the driving assembly  200  including the same configuration. For convenience of explanation, hereinafter, the same two driving assemblies  200  are expressed as a first driving assembly  201  and a second driving assembly  202 . 
     The first driving assembly  201  and the second driving assembly  202  may include the plurality of driving ICs  211  to  218 , a first connector  221 , a second connector  222 , and a memory  230  on a PCB substrate. 
     Particularly, the plurality of driving ICs  211  to  218  are elements that each drive a preset number of LEDs  300  to emit light. For example, the first driving IC  201  may drive 16*3 LEDs  300  corresponding to 16 pixels. In  FIG. 5 , it is illustrated that the first driving assembly  201  includes eight driving ICs  211  to  218 , but may include eight or more driving ICs depending on the number of LEDs  300  provided in the LED module  100 . 
     The first connector  221  of the second driving assembly  202  and the second connector  222  of the first driving assembly  201  may be connected by a cable  225 . 
     For example, the cable  225  may be provided with 51 pins, and the cable  225  may transmit a first control signal, a second control signal, and image data based on an allocated pin map. 
     Particularly, the first connector  221  of the first driving assembly  201  may be connected to a timing controller  173 . The timing controller  173  is a type of the processor  171  and may control the driving ICs  211  to  218  so that the plurality of LEDs  300  can output frame images. 
     In the conventional LED modules  100 , the timing controller  173  is provided for each LED module  100 . However, in the disclosed display apparatus  10 , the first LED module  101  is connected to the timing controller  173 , and the first driving assembly  201  and the second driving assembly  202  are connected to each other by the cable  225 . That is, the disclosed display apparatus  10  does not need to provide a separate timing controller  173  for each LED module  100 . 
     The first control signal, the second control signal, and the image data generated by the timing controller  173  may be transmitted to the first connector  221  of the first driving assembly  201  through another cable  226 , and the first driving assembly  201  may transmit the control signal and the image data to the second driving assembly  202  through the cable  225  connected to the second connector  222 . The driving ICs  211  to  218  of the second driving assembly  202  may be driven based on the image data. 
     Meanwhile, the timing controller  173  does not necessarily need to be connected to the first driving assembly  201  through an additional cable  226 , and may transmit the first control signal, the second control signal, and image data to the first driving assembly  201  in various methods. That is, the disclosed display apparatus  10  is sufficient if the first LED module  101  and the second LED module  102  transmit the control signals and the image data through the cable  225 . 
     Each of the first driving assembly  201  and the second driving assembly  202  may include the memory  230 . The memory  230  may store the calibration data, and may be provided as the non-volatile memory, for example the flash memory. The calibration data reflects different RGB characteristics at the time each LED module  100  was manufactured, and is stored for a certain quality of the output image. Accordingly, the calibration data may be different for each LED module  100 . 
     When the timing controller  173  transmits the first control signal to the first driving assembly  201  for selecting the second driving assembly  202 , the first driving assembly  201  may then transmit the first control signal to the second driving assembly  202 . According to the first control signal, the second driving assembly  202  may transmit the calibration data of the second LED module  102  stored in the memory  230  to the first driving assembly  201  through the cable  225 . In this way, the signal transmitted by the first driving assembly  202  to the timing controller  173  and the signal transmitted by the second driving assembly  202  to the first driving assembly  201  through the cable  225  are referred to as feedback signals. The timing controller  173  may receive the calibration data of the second LED module  102  through the first driving assembly  201 . 
     The disclosed display apparatus  10  does not need to provide the timing controller  173  for each LED module  100 , and may individually control each LED module  100  by allocating the first control signal to the pin map of the cable  225 . 
     Meanwhile, the first driving assembly  201  and the second driving assembly  202  may further include various configurations in addition to the above-described configurations. 
       FIG. 6  is a view for describing a driving connection state included in three LED modules according to an embodiment. Description of the overlapping items described in  FIG. 5  will be omitted. 
     Referring to  FIG. 6 , the display apparatus  10  may include three LED modules  101 ,  102 ,  103 . The first LED module  101  may include the first driving assembly  201 , the second LED module  102  may include the second driving assembly  202 , and the third LED module  103  may include a third driving assembly  203 . 
     The first driving assembly  201  may be connected to the timing controller  173  through the first connector  221 . The first cable  225  is inserted into the second connector  222  of the first driving assembly  201 . The second driving assembly  202  may be connected to the first cable  225  through the first connector  221 . The second cable  227  may be inserted into the second connector  222  of the second driving assembly  202 . The third driving assembly  203  may be connected to the second cable  227  through the first connector  221 . Through this, the first driving assembly  201  may transmit the first control signal, the second control signal, and the image data of the timing controller  173  to the third driving assembly  203 , and the third driving assembly  203  may transmit the feedback signal to the timing controller  173 . 
     The timing controller  173  may collect the calibration data for the first LED module  101 , calibration data for the second LED module  102 , and calibration data for the third LED module  103  before outputting the image. 
     The timing controller  173  may transmit the first control signal for selecting the first driving assembly  201 , and may receive the calibration data stored in the first memory  231  of the first driving assembly  201 . 
     The timing controller  173  may transmit the first control signal for selecting the second driving assembly  201  to the first driving assembly  201 . In this case, the first driving assembly  201  may transmit the first control signal to the second driving assembly  202  through the first cable  225 . The second driving assembly  202  may generate the feedback signal including the calibration data stored in the second memory  232  based on the first control signal. The second driving assembly  202  may transmit the feedback signal to the first driving assembly  201 . The timing controller  173  may receive the calibration data transmitted by the second driving assembly  202  from the first driving assembly  201 . 
     The timing controller  173  may transmit the first control signal for selecting the third driving assembly  201  to the first driving assembly  201 . The first driving assembly  201  may transmit the first control signal to the second driving assembly  202  through the first cable  225 . The second driving assembly  202  may transmit the first control signal to the third driving assembly  203  through the second cable  227 . The third driving assembly  203  may generate the feedback signal including calibration data stored in the third memory  233  based on the first control signal. The third driving assembly  203  may transmit the feedback signal to the second driving assembly  202 . The second driving assembly  202  may transmit the received feedback signal to the first driving assembly  201  through the first cable  225 . The first driving assembly  201  may transmit the feedback signal to the timing controller  173 , and the timing controller  173  may receive the calibration data included in the feedback signal. 
     Through this, the timing controller  173  may selectively receive the necessary calibration data from the plurality of LED modules  101 ,  102 , and  103 . 
     Meanwhile, each of the first LED module  101 , the second LED module  102 , and the third LED module  103  may include a switching mode power supply (SMPS)  181 ,  182 , and  183  respectively that supplies power to operate each component of the driving assembly  200  and the LED  300 . Particularly, a first SMPS  181 , a second SMPS  182 , and a third SMPS  183  may be connected to supply constant power through wiring without separately providing the connector  220  of the driving assembly  200 . 
       FIGS. 7 to 9  are views for describing an embodiment of a first control signal for selecting an LED module. It will be described together below in order to avoid redundant description. 
     The timing controller  173  may transmit the first control signal for selecting the driving assembly  200  through 3 pins allocated among 51 pins. 
     Referring to  FIG. 7 , in order to select the third driving assembly  203 , the timing controller  173  may transmit a first control signal of 1, 1, and 1 through the 3 pins of 51 pins. 
     The first connector  221  of the first driving assembly  201  may receive 1, 1, and 1. A third pin of the 3 pins in the second connector  222  may be connected to a ground. In addition, a second pin of the first connector  221  may be connected to a first pin of the second connector  222  on the PCB board. 
     The first driving assembly  201  may pass the first control signal based on the first and second signals being 1 and 1. In other words, as shown in  FIG. 7 , the first and second signals being 1 and 1 cause the first driving assembly  201  not to transmit any calibration data. 
     Since the third pin of the second connector  222  of the first driving assembly  201  is connected to the ground, the second driving assembly  202  may receive 1, 1, and 0 from the first driving assembly  201  through the first connector  221 . 
     In the second connector  222  of the second driving assembly  202 , the second pin of the 3 pins may be connected to the first connector  221  and the third pin may be connected to the ground. Like the first driving assembly  201 , the second driving assembly  202  may pass the first control signal based on the first and second signals being 1 and 1 and may not transmit any calibration data. However, the control signal 1, 0, and 0 may be transmitted to the third driving assembly  203 . 
     The third driving assembly  203  may transmit the calibration data stored in the memory  230  to the timing controller  173  based on the first and second signals being 1 and 0. 
     Meanwhile, the third pin of the 3 pins in the second connector  222  of the third driving assembly  203  may also be connected to the ground. 
     Referring to  FIG. 8 , in order to select the second driving assembly  202 , the timing controller  173  may transmit the first control signal of 1, 1, and 0 through the 3 pins of the 51 pins. 
     The first connector  221  of the first driving assembly  201  may receive 1, 1, and 0. Based on the first and second signals being 1 and 1, the first driving assembly  201  may pass the first control signal and may not transmit any calibration data. 
     Like  FIG. 7 , in the second connector  222  of the first driving assembly  201 , the second pin of the 3 pins may be connected to the first connector  221  of the first driving assembly  202 , and the third pin may be connected to the ground. Therefore, the second connector  222  of the first driving assembly  201  may transmit 1, 0, and 0 to the second driving assembly  202 . 
     The second driving assembly  202  may receive 1, 0, and 0 from the first driving assembly  201  through the first connector  221 . The second driving assembly  202  may transmit the calibration data stored in the memory  232  to the timing controller  173  based on the first and second signals being 1 and 0. 
     As illustrated in  FIG. 7 , in the second connector  222  of the second driving assembly  202 , the second pin of the 3 pins may be connected to the first connector  221  of the third driving assembly  203 , and the third pin may be connected to the ground. Therefore, 0, 0, and 0 may be transmitted to the third driving assembly  203  through the second connector  222  of the second driving assembly  202 . 
     The third driving assembly  203  does not transmit the calibration data stored in the memory  233  based on the first control signal of 0 and 0. 
     Referring to  FIG. 9 , in order to select the first driving assembly  202 , the timing controller  173  may transmit the first control signal of 1, 0, and 0 through 3 pins of 51 pins. The first driving assembly  201  may transmit the calibration data stored in the memory  231  to the timing controller  173  based on the first and second signals being 1 and 0. 
     Like  FIG. 7 , in the second connector  222  of the first driving assembly  201 , the second pin of the 3 pins may be connected to the first connector  221  of the second driving assembly  202 , and the third pin may be connected to the ground. Therefore, the second connector  222  of the first driving assembly  201  may transmit 0, 0, and 0 to the second driving assembly  202 . The second driving assembly  202  does not transmit the calibration data stored in the memory  232  based on the first control signal of 0 and 0. 
     As illustrated in  FIG. 7 , in the second connector  222  of the second driving assembly  202 , the second pin of the 3 pins may be connected to the first connector  221  of the third driving assembly  203 , and the third pin may be connected to the ground. Therefore, the second connector  222  of the second driving assembly  202  may transmit 0, 0, and 0 to the third driving assembly  203 . The third driving assembly  203  does not transmit the calibration data stored in the memory  233  based on the first control signal of 0 and 0. 
     Meanwhile, a method of allocating the first control signal to the pin map by the timing controller  173  or a reference of the signal for selecting the LED module may be variously changed. For example, when the display apparatus  10  is connected to four or more LED modules  100  through the cable  220 , the signal for selecting the LED module  100  through the first control signal different from  FIGS. 7 to 9  may also be transmitted. 
       FIGS. 10 to 12  are views of a pin map for describing a second control signal. It will be described together below in order to avoid redundant description. 
     The display apparatus  10  may connect the timing controller  173 , the first LED module  101 , the second LED module  102 , and the third LED module  103  as shown in the figures. 
     The timing controller  173 , the first LED module  101 , the second LED module  102 , and the third LED module  103  may connect to each driving assembly  201 ,  202 , and  203  through the cables  225  and  226  composed of 51 pins and the connector  221  and  222  into which the cables  225  and  227  are inserted. 
     Referring to  FIG. 10 , the timing controller  173  may allocate the first control signal for selecting the first LED module  101 , the second LED module  102 , and the third LED module  103  at pins  49 ,  50 , and  51 . That is, FLASH_SEL  1 , FLASH_SEL  2  and FLASH_SEL  3  illustrated in  FIG. 10  denote the first control signal allocated to the pin map. 
     Meanwhile, the timing controller  173  may allocate the second control signal to pin  1  of 51 pin maps as DATA_SEL. That is, the first driving assembly  201  may select whether to transmit the first control signal or the image data to the second driving assembly  202  based on the second control signal. 
     Particularly, the first driving assembly  201  of the first LED module  101  may receive the first control signal, the second control signal, and the image data from the timing controller  173 . The plurality of driving ICs  210  provided in the first driving assembly  201  may be driven based on image data. Each of the plurality of driving ICs  210  provided in the first driving assembly  201  may transmit the image data and the control signals (the first control signal and the second control signal) in a cascade form. Here, the last driving IC among the plurality of driving ICs  210  provided in the first driving assembly  201  may change the second control signal to 1 or 0. In the embodiment of  FIG. 10 , since the first cable  225  is connected to the second connector  222 , the last driving IC of the first driving assembly  201  may change the second control signal to 1, that is, pull-up. 
     The second LED module  102  may be connected to the third LED module  103 . Accordingly, the second connector  222  of the second driving assembly  202  may be connected to the third driving assembly  203  through the second cable  227 . The second driving assembly  202  may also transmit the second control signal connected from the first driving assembly  201  to the third driving assembly  203  while pulling-up. 
     The second connector  222  of the third driving assembly  203  is not connected with an additional cable. Therefore, the third driving assembly  203  may pull-down the second control signal to zero. 
     Based on the pull-down signal, the third driving assembly  203  may transmit the feedback signal to the timing controller  173 . The feedback signal may be allocated to another pin, for example, pin  2  to which the first control signal and the second control signal are not allocated. In addition, according to the embodiment, when the third driving assembly  203  transmits the calibration data to the timing controller  173 , the calibration data may be inserted into pins  3  to  48 . 
     Referring to  FIG. 11 , the display apparatus  10  may connect to the timing controller  173 , the first LED module  101 , and the second LED module  102 . 
     The timing controller  173  may allocate the second control signal to the first pin. 
     The first driving assembly  201  of the first LED module  101  may receive the first control signal, the second control signal, and the image data. The second connector  222  of the first driving assembly  201  may be connected to the second driving assembly  202  through the cable  225 . Based on this connection state, the first driving assembly  201  may change the second control signal to 1. The first driving assembly  201  may transmit a signal including a pull-up signal and the control signal to the second driving assembly  202 . 
     The second connector  222  of the second driving assembly  202  is not connected with the additional cable. Accordingly, the second driving assembly  202  may pull-down the second control signal to zero. In addition, when pulled down to 0, the second driving assembly  202  may transmit the feedback signal to the first driving assembly  201 . 
     Referring to  FIG. 12 , the display apparatus  10  may not have an additional LED module  100  connected to the first LED module  101 . The first driving assembly  201  may pull-down the signal to 0 to the first pin and transmit the feedback signal. The timing controller  173  may confirm that the additional LED module is not connected to the first LED module  101  through this. 
     Meanwhile, the pin maps illustrated in  FIGS. 10 to 12  are only an example. Therefore, the second control signal is not necessarily allocated to pin  1 , but may be allocated to a plurality of pins. 
       FIG. 13  is a flowchart illustrating operations of a display apparatus according to an embodiment. 
     Referring to  FIG. 13 , in the display apparatus  10 , the first driving assembly  201  of the first LED module  101  and the second driving assembly  202  of the second LED module  102  may be connected through the connector  220  and the first cable  225 . 
     The processor  171 , for example, the timing controller  173  may transmit the image data and the first control signal to the first driving assembly  201  ( 400 ). 
     Here, the first control signal is a selection signal for receiving the calibration data of the first driving assembly  201  or the second driving assembly  201 . 
     The first driving assembly  201  may transmit the image data and the first control signal to the second driving assembly  202  through the first cable  225  ( 410 ). 
     Particularly, the first driving assembly  201  does not insert the calibration data stored in the first memory  231  based on the first control signal including the selection signal of the second LED module  102 . 
     The second driving assembly  202  may generate the feedback signal including the calibration data based on the first control signal ( 420 ). 
     Particularly, the feedback signal is a signal in which data insertion or data change is performed according to the first control signal transmitted from the first driving assembly  202  is retransmitted again through the first cable  225 . 
     The second driving assembly  202  may transmit the feedback signal to the first driving assembly through the first cable  225  ( 430 ), and the first driving assembly  201  may transmit the feedback signal to the processor  171  ( 440 ). 
     The processor  171  may receive the feedback signal ( 450 ). 
     The processor  171  may perform image processing based on the calibration data of the second LED module  102  included in the feedback signal, and output the image according to each LED module  100 , thereby reducing a sense of heterogeneity, such as a difference in contrast, felt by the user. 
       FIG. 14  is a flowchart illustrating operations of a display apparatus according to an embodiment. 
     Like  FIG. 14 , in the display apparatus  10 , the first driving assembly  201  of the first LED module  101  and the second driving assembly  202  of the second LED module  102  may be connected through the connector  220  and the first cable  225 . 
     The processor  171  may transmit the image data and the second control signal to the first driving assembly  201  ( 500 ), and the first driving assembly  201  may change the second control signal to 1 ( 510 ). 
     When the second connector  222  of the first driving assembly  201  is connected through the first cable  225 , at least one driving IC of the first driving assembly  201  may pull up a part of the second control signal. 
     The first driving assembly  201  may transmit the image data and the second control signal to the second driving assembly  202  through the first cable  225  ( 520 ). 
     Here, the second control signal may include the pull-up signal. 
     The second driving assembly  202  may change the second control signal to 0 ( 530 ). 
     The second connector  222  of the second driving assembly  202  may not be connected to the additional cable  225 . At least one driving IC of the second driving assembly  202  may pull up a part of the control signal. 
     The second driving assembly  202  may transmit the feedback signal including the changed second control signal to the first driving assembly  201  through the first cable  225  ( 540 ), and the first driving assembly  201  may transmit the feedback signal to the processor  171  ( 550 ). 
     According to the display apparatus and the method of controlling the display apparatus according to the embodiments, it is possible to improve power efficiency and operating efficiency of the driving IC, and control the plurality of LED modules by one main board controlling at least two LED modules. 
     Embodiments of the disclosure have thus far been described with reference to the accompanying drawings. It should be obvious to a person of ordinary skill in the art that the disclosure may be practiced in other forms than the embodiments as described above without changing the technical idea or essential features of the disclosure. The above embodiments are only by way of example, and should not be interpreted in a limited sense.