Abstract:
A driving device includes a memory configured to store an initial setting value to drive a display, a power source controller configured to output a pulse width modulation (PWM) signal controlling power applied to the display, and a switching unit configured to connect an input and output port to the memory when writing data to a memory and configured to connect the power source controller to the input and output port when driving the display.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2013-0022380 filed in the Korean Intellectual Property Office on Feb. 28, 2013, the entire contents of which are incorporated herein by reference. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    Embodiments relate to a driving device, a display device including the same, and a driving method thereof. 
         [0004]    2. Description of the Related Art 
         [0005]    In operation of a display device, a deviation may be generated between display luminance according to an actual display luminance and grayscale data of the display device. Compensation of such a deviation may enhance an image displayed on the display device. 
         [0006]    The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
       SUMMARY 
       [0007]    Embodiments are directed to a driving device, including a memory configured to store an initial setting value to drive a display, a power source controller configured to output a pulse width modulation (PWM) signal controlling power applied to the display, and a switching unit configured to connect an input and output port to the memory when writing data to a memory and configured to connect the power source controller to the input and output port when driving the display. 
         [0008]    The switching unit may be configured to connect the memory and the power source controller to the input and output port through one wire. 
         [0009]    The driving device may further include a connection controller configured to control the switching unit, and the connection controller may be configured to provide the initial setting value to the memory when writing the data to the memory and provide the PWM signal to the power source controller when driving the display. 
         [0010]    The memory may be configured to fix the initial setting value written thereto by using a voltage applied from the switching unit after writing the initial setting value provided from the connection controller. 
         [0011]    The power source controller may be configured to output the PWM signal provided from the connection controller to the input and output port through the switching unit. 
         [0012]    The PWM signal output by the power source controller may control an ELVSS voltage. 
         [0013]    Embodiments are also directed to a display device including a driving device according to an embodiment. 
         [0014]    Embodiments are also directed to a display device, including a driving device including a memory configured to store an initial setting value to drive a display and a power source controller configured to output a pulse width modulation (PWM) signal controlling a power source voltage supplied to the display, and a switching unit configured to connect an input and output port to the memory when writing data to a memory and connect the power source controller to the input and output port when driving the display. 
         [0015]    The driving device may further include a connection controller configured to control the switching unit according to an operation state of writing the data to the memory and driving the display. 
         [0016]    The switching unit may include a first switching transistor configured to connect to the memory and configured to apply an MTPHV voltage to the memory, and a second switching transistor configured to connect to the power source controller and output the PWM signal of the power source controller to control a DC-DC converter. 
         [0017]    The connection controller may be configured to apply a VGL voltage ON to a gate of the first switching transistor, apply the MTPHV voltage to the memory, and apply a VGH voltage OFF to a gate of the second switching transistor when writing the data to the memory. 
         [0018]    The connection controller may be configured to apply the VGH voltage OFF to the gate of the first switching transistor and apply the VGL voltage ON to the gate of the second switching transistor to output the PWM signal of the power source controller to the input and output port when driving the display. 
         [0019]    Embodiments are also directed to a method of driving a display device by a driving device, the method including a controlling operation of outputting a control signal according to an operation state of writing data to a memory and driving a display, a switching operation of connecting a memory or a power source controller to an input and output port by a switching unit according to a control signal, and a driving operation of applying a voltage to the memory or outputting a signal of the power source controller to the input and output port according to the switching operation. 
         [0020]    In the driving operation, if the memory is connected to the input and output port, an MTPHV voltage may be applied to the memory to fix an initial setting value that is written to the memory. 
         [0021]    In the driving operation, if the power source controller is connected to the input and output port, a PWM signal controlling a DC-DC converter may be output to the input and output port. 
         [0022]    In the driving operation, the MTPHV voltage may be applied to the memory or the PWM signal of the power source controller is output through one wire. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]    Features will become apparent to those of skill in the art by describing in detail example embodiments with reference to the attached drawings in which: 
           [0024]      FIG. 1  is a view of a portion of a general driving integrated circuit. 
           [0025]      FIG. 2  is a view of a display device including a driving device according to an example embodiment. 
           [0026]      FIG. 3  is a block diagram of a driving device according to an example embodiment. 
           [0027]      FIG. 4  is a circuit diagram showing a structure of a display device pixel. 
           [0028]      FIG. 5  is a view of a display device including a driving device according to another example embodiment. 
           [0029]      FIG. 6  is a block diagram of a portion of a display device according to another example embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    In the following detailed description, only certain example embodiments have been shown and described, simply by way of illustration. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification. 
         [0031]    Throughout this specification and the claims that follow, when it is described that an element is “coupled” to another element, the element may be “directly coupled” to the other element or “electrically coupled” to the other element through a third element. In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. 
         [0032]      FIG. 1  is a view of a portion of a general driving integrated circuit. 
         [0033]    Multi-time programming (hereafter referred to as “MTP”) may be used to compensate a reference gamma voltage to remove a deviation generated between display luminance according to an actual display luminance and grayscale data of the display device. For this, grayscale data information according to a video signal may be stored to an MTP memory. The grayscale data information is information determining a data voltage supplied to a corresponding pixel. 
         [0034]      FIG. 1  is a view showing a structure for applying an MTPHV voltage to a driving integrated circuit from the outside for the MTP. For this, six pins are allocated to separately apply the MTPHV voltage to an MTP memory  4 . 
         [0035]    Here, the MTPHV voltage is a signal that is only operated when deleting or writing the data to the MTP memory  4  and is in a floating state during non-operation such that the wire applying the MTPHV voltage may influence EMI, and an FPC area and a separate pin for a connector are allocated to apply the MTPHV voltage. 
         [0036]    Also, an ESD protection circuit for the MTPHV voltage signal may be separately formed on the driving integrated circuit and the FPC. 
         [0037]      FIG. 2  is a view of a display device including a driving device according to an example embodiment. 
         [0038]    Referring to  FIG. 2 , a display device includes a display unit  10 , a scan driver  20 , a data driver  30 , a signal controller  40 , a DC-DC converter  50 , and an input and output port  160 . 
         [0039]    The display unit  10  includes a plurality of scan lines S 1 -Sn, a plurality of data lines D 1 -Dm, and a plurality of pixels connected to the plurality of signal lines S 1 -Sn and D 1 -Dm and arranged in an approximate matrix. The plurality of scan lines S 1 -Sn extend in an approximate row direction and approximately parallel to each other. The plurality of data lines D 1 -Dm extend in an approximate column direction and approximately parallel to each other. 
         [0040]    The scan driver  20  is connected to the plurality of scan lines S 1 -Sn and generates a plurality of scan signals according to a first driving control signal. The scan driver  20  sequentially applies the scan signals of a gate-on voltage to the plurality of scan lines S 1 -Sn. 
         [0041]    The data driver  30  is connected to the plurality of data lines D 1 -Dm, samples and holds the image data signal DAT according to a second driving control signal, and applies a plurality of data signals to the plurality of data lines D 1 -Dm. The data driver  300  applies the data signal having a predetermined voltage range to the plurality of data lines D 1 -Dm by corresponding to the scan signals of the gate-on voltage to write the data to the plurality of pixels. 
         [0042]    The signal controller  40  receives video signals R, G, and B, and a synchronization signal that are input from the outside. The video signals R, G, and B include luminance information of each pixel PX, and the luminance has a grayscale having a predetermined number, for example 1024=2 10 , 256=2 8 , or 64=2 6 . For example, the input control signals may include a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a main clock signal MCLK, and a data enable signal DE. 
         [0043]    The signal controller  40  divides the video signals R, G, and B by a frame unit according to the vertical synchronization signal Vsync, and divides the video signals R, G, and B by a scan line unit according to the horizontal synchronization signal Hsync to generate the image data signal DAT. The signal controller  40  transmits the image data signal DAT along with the first driving control signal to the data driver  30 . 
         [0044]    Also, the signal controller  40  includes a driving device  100 . The driving device  100  receives an MTPHV voltage to fix a data written to the memory and provides a PWM signal controlling a power source voltage supplied to the display using the DC-DC converter  50 . 
         [0045]    According to the present example embodiment, an MTPHV voltage is applied or a PWM signal is provided through one wire  170  between the driving device  100  of the signal controller  40  and the input and output port  160 . 
         [0046]    The DC-DC converter  50  receives a PWM signal from the signal controller  40  and applies power source voltages ELVDD and ELVSS to the display unit  10  for the driving. 
         [0047]      FIG. 3  is a block diagram of a driving device according to an example embodiment. 
         [0048]    The driving device  100  outputs a control signal controlling the display unit  10 , and includes a pin for the input and output of various signals. The driving device  100  may output the control signal through an output pin for the control signal. 
         [0049]    Referring to  FIG. 2 , the driving device  100  includes a power source controller  110 , a memory  120 , a connection controller  130 , and a switching unit  140 . 
         [0050]    The power source controller  110  outputs a PWM signal controlling the DC-DC converter  50 . The DC-DC converter is provided outside the display unit  10  and applies the power source voltages ELVDD and ELVSS to the display unit  10 . 
         [0051]      FIG. 4  is a circuit diagram of a structure of a pixel of a display unit. An example embodiment is not limited thereto. 
         [0052]    The pixel shown in  FIG. 4  is connected to the i-th scan line Si and the j-th data line Dj. 
         [0053]    As shown in  FIG. 4 , the pixel includes a switching transistor TS, a driving transistor TD, a capacitor Cst, and an organic light emitting element OLED. 
         [0054]    The switching transistor TS includes a gate electrode connected to the scan line Si, a first electrode connected to the data line Dj, and a second electrode connected to the gate electrode of the driving transistor TD. 
         [0055]    The driving transistor TD includes the source electrode connected to the voltage ELVDD, the drain electrode connected to an anode of the organic light emitting element (OLED), and the gate electrode connected to the switching transistor TS. 
         [0056]    The capacitor Cst is connected between the gate electrode and the source electrode of the driving transistor TD, and the cathode of the organic light emitting element (OLED) is connected to the voltage ELVSS. 
         [0057]    When the scan signal transmitted through the scan line Si is low level, the switching transistor TS is turned on, and the capacitor C is charged by the data signal transmitted through the data lines Dj. 
         [0058]    The gate voltage of the driving transistor TD is constantly maintained by the capacitor C for a next scan, and the driving current of the driving transistor TD is generated depending on a difference of the gate-source voltage. The organic light emitting device (OLED) emits light according to the driving current. 
         [0059]    According to the present example embodiment, the power source controller  110  outputs a PWM signal controlling the voltage ELVSS among the voltages ELVDD and ELVSS that is a voltage used for light emission of the pixel of the display unit  10 . 
         [0060]    Also, the power source controller  110  receives the PWM signal from the connection controller  130 , and may output the PWM signal to the input and output port  160  through the switching unit  140 . 
         [0061]    The memory  120  stores an initial setting value for the display driving. The memory  120  may be included in an MTP block portion according to an example embodiment. 
         [0062]    According to the present example embodiment, the initial setting value stored to the memory  120  includes a gamma value, a power voltage setting value, panel driving timing, and an I/F setting value. 
         [0063]    The driving device  100  writes the initial setting value provided from the connection controller  130  to the memory  120  and then fixes the written initial setting value by using the MTPHV voltage applied from the switching unit  140 . 
         [0064]    The connection controller  130  generates the various control signals and controls each element of the driving device  100  by the control signals. 
         [0065]    The connection controller  130  controls the operation of the switching unit  140  and controls the operation of the switching unit  140  according to the operation state of writing the data to the memory  120  and driving the display, etc. 
         [0066]    Also, the connection controller  130  receives the various signals from a register  150 . The initial setting value for the display driving may be provided to the memory  120  when writing the data to the memory  120 , and the PWM signal to control the external DC-DC converter may be provided to the power source controller  110  when driving the display. 
         [0067]    The switching unit  140  connects the power source controller  110  or the memory  120  to the input and output port  160  according to the control of the connection controller  130 . 
         [0068]    For example, the switching unit  140  connects the memory  120  and the input and output port  160  when writing the data to the memory  120 , and connects the power source controller  110  and the input and output port  160  when driving the display. 
         [0069]    According to the present example embodiment, the PWM signal of the power source controller  110  may be output through the input and output port  160  to control the external DC-DC converter when connecting the power source controller  110  and the input and output port  160 . 
         [0070]    Further, the MTPHV voltage provided from the outside is applied to the memory  120  to write to or delete the data from the memory  120  when connecting the memory  120  and the input and output port  160 . 
         [0071]    According to the present example embodiment, the switching unit  140  connects the power source controller  110  and the memory  120  to the input and output port  160  through one wire  170 . 
         [0072]    Accordingly, since the driving device  100  controls the DC-DC converter  50  and simultaneously applies the voltage to the memory  120  through one wire  170 , the area of the driving device  100  and the number of pins may be reduced. 
         [0073]      FIG. 5  is a view of a display device including a driving device according to another example embodiment. 
         [0074]    Referring to  FIG. 5 , the display device includes the display unit  10 , the scan driver  20 , the data driver  30 , the signal controller  40 , the DC-DC converter  50 , and an input and output port  260 . Here, the display unit  10 , the scan driver  20 , the data driver  30 , and the DC-DC converter  50  are the same as that shown in  FIG. 1  such that the description thereof is omitted. 
         [0075]    The signal controller  40  includes a driving device  200 . The driving device  200  receives the MTPHV voltage to fix the data written to the memory, and provides the PWM signal controlling the power supplied to the display to the DC-DC converter  50 . 
         [0076]    A switching unit  240  is disposed between the driving device  200  and the input and output port  260  of the signal controller  40 . Also, the switching unit  240  and the input and output port  260  receive the MTPHV voltage and provide the PWM signal through one wire  270 . 
         [0077]      FIG. 6  is a block diagram of a portion of a display device according to another example embodiment. 
         [0078]    Referring to  FIG. 6 , the display device includes the driving device  200 , the switching unit  240 , a register  250 , and the input and output port  260 . 
         [0079]    The driving device  200  outputs the control signal controlling the display device, and includes a power source controller  210 , a memory  220 , and a connection controller  230  according to an example embodiment. 
         [0080]    Here, the power source controller  210  and the memory  220  are the same as the power source controller  110  and the memory  120  of  FIG. 3  such that the detailed description thereof is omitted. 
         [0081]    The switching unit  240  connects the power source controller  210  or the memory  220  to the input and output port  260  according to the control of the connection controller  230 . 
         [0082]    The switching unit  240  includes a first switching transistor  242  and a second switching transistor  244  realized on the panel according to an example embodiment, as shown in  FIG. 4 . 
         [0083]    The first switching transistor  242  and the second switching transistor  244  are formed on the panel, and may be realized by a CMOS transistor, e.g., a PMOS transistor or an NMOS transistor. The operation state that is realized by the PMOS transistor will now be described. 
         [0084]    The first switching transistor  242  includes the gate connected to the connection controller  210 , the source connected to the power source controller  210 , and the drain connected to the input and output port  260 . 
         [0085]    The first switching transistor  242  outputs the PWM signal of the power source controller  210  to the input and output port  260  according to the control of the connection controller  230 . 
         [0086]    Also, the second switching transistor  244  includes the gate connected to the connection controller  210 , the source connected to the input and output port  260 , and the drain connected to the memory  220 . 
         [0087]    The second switching transistor  244  applies the external voltage MTPHV to the memory  220  according to the control of the connection controller  230 . 
         [0088]    Thus, the connection controller  230  applies the VGH voltage OFF to the gate of the first switching transistor  242  and the VGL voltage ON to the gate of the second switching transistor  244  when writing the data to the memory  220 . 
         [0089]    When writing the data to the memory  220 , after the initial setting value for driving the display is written to the memory  220 , the MTPHV voltage is applied through the second switching transistor  244  thereby fixing the initial setting value. 
         [0090]    Also, when driving the display, the connection controller  230  applies the VGL voltage ON to the gate of the first switching transistor  242  and the VGH voltage OFF to the gate of the second switching transistor  244 . 
         [0091]    Accordingly, when driving the display driving, the power source controller  210  may output the PWM signal to the input and output port  260  through the first switching transistor  242 . 
         [0092]    The driving method includes a controlling operation, a switching operation, and a driving operation. 
         [0093]    In the controlling operation, the connection controllers  130  and  230  write the data to the memories  120  and  220  or output the control signal according to the operation state driving the display of the display device to control the switching units  140  and  240 . 
         [0094]    In the switching operation, according to the control signal of the connection controllers  130  and  230 , the switching units  140  and  240  connect the memories  120  and  220  or the power source controllers  110  and  210  to the input and output ports  160  and  260 . 
         [0095]    Also, in the driving operation, according to the connection state of the switching units  140  and  240 , the voltage is applied to the memories  120  and  220 , or the signal of the power source controllers  110  and  210  is output to the input and output ports  160  and  260 . 
         [0096]    In the driving operation, if the memories  120  and  220  are connected to the input and output ports  160  and  260 , to fix the initial setting value that is written to the memories  120  and  220  or is deleted, the external MTPHV voltage is applied to the memories  120  and  220  through the input and output ports  160  and  260  and the switching units  140  and  240 . 
         [0097]    Also, in the driving operation, if the power source controllers  110  and  210  are connected to the input and output ports  160  and  260 , the PWM signal controlling the DC-DC converter is output to the input and output ports  160  and  260 . At this time, the power source controllers  110  and  210  output the PWM signal controlling the ELVSS voltage. 
         [0098]    Accordingly, the present example embodiment applies the external voltage to the memories  120  and  220  or the signal of the power source controllers  110  and  210  to the outside through one of the wires  170  and  270 . Thus, general separated circuits may be combined into one, thereby reducing the area of the driving device and the number of pins. 
         [0099]    Also, the present example embodiment adds the GND wire by the reduction of the number of connector pins and deletes the MTPHV wire of the floating state when driving the module, thereby helping to enhance the EMI characteristic. Further, the present example embodiment may realize the ESD preventing circuits, which are generally separately formed, into one circuit. 
         [0100]    Embodiments may also be implemented by a program realizing functions corresponding to the construction of the example embodiments, and a recording medium on which the program is recorded, in addition to the device and method described above. 
         [0101]    By way of summation and review, a display device may have different information written to an MTP memory according to a characteristic. The MTP memory may be included in a driving integrated circuit D-IC of the display device, and an MTPHV voltage is supplied to the MTP memory to write new information to the MTP memory. Also, a separate pin or wire to transmit the MTPHV voltage to the MTP memory is allocated in a general driving integrated circuit. 
         [0102]    As described above, embodiments may provide a device and a method for applying a MTPHV voltage to a driving device through one wire. According to embodiments, by applying the voltage to the driving device and controlling the DC-DC converter through one wire, the area of the driving device and the number of pins may be reduced. Also, embodiments may realize separate circuits through one circuit to help enhance the EMI characteristic, and the ESD preventing circuits that are respectively formed as separate circuits may be realized through one. 
         [0000]    
       
         
               
             
               
               
               
             
               
               
             
           
               
                   
               
               
                 &lt;Description of Symbols&gt; 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 10: display unit 
                 20: scan driver 
                 30: data driver 
               
               
                 40: signal controller 
                 50: DC-DC 
                 100, 200: driving device 
               
               
                   
                 converter 
               
             
          
           
               
                 110, 210: power source controller 
                 120, 220: memory 
               
               
                 130, 230: connection controller 
                 140, 240: switching unit 
               
               
                 150, 250: register 
                 160, 260: input and output port 
               
               
                 170, 270: wire 
                 242: first switching transistor 
               
               
                 244: second switching transistor 
               
               
                   
               
             
          
         
       
     
         [0103]    Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.