Display device and driving method thereof

Abstract

A display device and a driving method thereof are provided. A method of driving a display device according to one embodiment of the present specification includes: receiving pixel data of an input image; storing the pixel data in a memory; comparing the variation between the Nth row of data (N is a natural number) and the (N + 1) th row of data stored in the memory with a preset reference value; when the variation between the Nth row of data and the (N + 1) th row of data is greater than or equal to a reference value, the Nth row of data and the (N + 1) th row of data are sequentially transmitted to the source driver IC, and when the variation between the Nth row of data and the (N + 1) th row of data is less than the reference value, the driving power of the source driver IC is cut off. Therefore, current consumption can be reduced.

Description

[0001] Cross - reference to related applications

[0002] This application claims the priority and benefit of Korean Patent Application No. 10 - 2023 - 0197298, filed on December 29, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical field

[0003] This specification relates to a display device and a driving method thereof, and more particularly, to a display device and a driving method thereof that selectively use single - bank driving or double - bank driving by detecting the occurrence of data transitions in a double - bank type display device. Background art

[0004] With the development of information technology, many related technologies have been developed in the field of display devices for presenting visual information through videos or images. The display device includes: a display panel including a plurality of sub - pixels, a driver circuit configured to apply signals for driving the display panel, a power supply unit configured to supply power to the display panel, etc. The driver circuit includes a gate driver circuit and a data driver circuit configured to supply a gate signal and a data signal to the display panel, respectively.

[0005] To drive the display device, a data driver integrated circuit (IC) and a gate driver IC, which are respectively connected to data lines and gate lines, are mounted on one side or the other side of the display panel in various ways, and the display device can selectively use a single - bank method or a double - bank method to drive the data driver IC and the gate driver IC according to the position of each driver IC in the driver ICs. In addition, according to the arrangement form of the source driver IC, the display device can be divided into a single - bank type display device and a double - bank type display device. In the single - bank type display device, the source driver IC chip is only provided on one edge of the display panel, while in the double - bank type display device, the source driver IC chips are distributed and provided on two corresponding edges of the display panel. Summary of the invention

[0006] This specification aims to provide a display device and a driving method thereof that can selectively use single - bank driving or double - bank driving to reduce current consumption by detecting the occurrence of data transitions in a double - bank type display device.

[0007] This specification also aims to provide a display device and a driving method thereof, which can control the driving of a source driver integrated circuit (IC) by detecting whether data transition occurs in pixels of a display panel.

[0008] This specification also aims to provide a display device and a driving method thereof, which can selectively drive a source driver IC in association with an area where no data transition occurs.

[0009] The objectives of this specification are not limited to the above objectives, and those skilled in the art will clearly understand other objectives not described herein from the following description.

[0010] According to an aspect of the present invention, a method for driving a display device is provided. The method includes: receiving pixel data of an input image; storing the pixel data in a memory; comparing a change amount between the Nth row data (N is a natural number) stored in the memory and the (N + 1)th row data with a preset reference value; when the change amount between the Nth row data and the (N + 1)th row data is greater than or equal to the reference value, sequentially transmitting the Nth row data and the (N + 1)th row data to a source driver integrated circuit (IC), and when the change amount between the Nth row data and the (N + 1)th row data is less than the reference value, cutting off driving power of the source driver IC; wherein the Nth row data includes pixel data of pixels of the Nth pixel row written to the display panel, and the (N + 1)th row data includes pixel data of pixels of the (N + 1)th pixel row written to the display panel.

[0011] According to another aspect of the present invention, a display device is provided, including: a display panel on which a plurality of data lines, a plurality of gate lines, and a plurality of pixels are provided; a plurality of source driver integrated circuits configured to convert received pixel data into a data voltage and supply the data voltage to the data lines; a timing controller configured to receive an input image and transmit the pixel data to the source driver IC; and a power supply unit configured to output power for driving the source driver IC under the control of the timing controller, wherein the timing controller is configured to store pixel data of the input image in a memory, compare a change amount between the Nth row data (N is a natural number) stored in the memory and the (N + 1)th row data with a preset reference value, when the change amount between the Nth row data and the (N + 1)th row data is greater than or equal to the reference value, sequentially transmit the Nth row data and the (N + 1)th row data to the source driver IC, and when the change amount between the Nth row data and the (N + 1)th row data is less than the reference value, control the power supply unit and cut off driving power of the source driver IC.

[0012] Details of other embodiments are included in the detailed description and the drawings. Description of the Drawings

[0013] The above and other objects, features, and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing exemplary embodiments of the present invention in detail with reference to the accompanying drawings, in which:

[0014] Figure 1 is a block diagram of a display device according to an embodiment of the present specification;

[0015] Figure 2 is a diagram briefly showing a data line configuration of a display device according to an embodiment of the present specification;

[0016] Figure 3A is a diagram showing a method of driving a display device according to an embodiment of the present specification;

[0017] Figure 3B is a diagram showing a method of driving a display device according to another embodiment of the present specification;

[0018] Figure 3C is a diagram showing a method of driving a display device according to still another embodiment of the present specification;

[0019] Figure 4 is a diagram conceptually showing a method of detecting whether a data transition has occurred according to an embodiment of the present specification;

[0020] Figure 5 is a diagram showing a method of setting a block when detecting whether a data transition has occurred according to an embodiment of the present specification;

[0021] Figures 6A to 6C is a diagram for describing a method of using a lookup table when detecting whether a data transition has occurred according to an embodiment of the present specification;

[0022] Figure 7 is a diagram briefly showing a switching circuit configured to control a source driver integrated circuit (IC) according to an embodiment of the present specification;

[0023] Figure 8 is a diagram showing in more detail Figure 7 the switching circuit; and

[0024] Figure 9A and Figure 9B are diagrams showing exemplary cases of applying a method of driving a display device according to an embodiment of the present specification to a display device. Detailed Description

[0025] The advantages, features, and methods for implementing the present invention will become clear from the following embodiments described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various other forms. These embodiments complete the disclosure of the present invention and are provided to enable those of ordinary skill in the art to which the present invention pertains to fully understand the scope of the present disclosure. The present invention is defined only by the scope of the claims.

[0026] The drawings, dimensions, ratios, angles, quantities, etc. disclosed in the accompanying drawings for describing the embodiments of the present invention are merely illustrative and are not limited to the details shown in the present invention. The same reference numerals always refer to the same elements. In addition, when determining that a detailed description of well-known technologies may unnecessarily obscure the gist of the present invention, the detailed description of well-known technologies will be omitted. Unless terms such as "comprising," "having," and "consisting of" used herein are used together with the term "only," these terms are intended to allow the addition of other elements. When a component is expressed in the singular form, it may include cases where the plural form is included unless otherwise clearly stated.

[0027] Even if not explicitly stated, components are interpreted as including a normal error range.

[0028] For describing positional relationships, for example, when the positional relationship between two parts is described as "above," "on," "under," "near," etc., unless the term "immediately" or "directly" is used in the expression, one or more parts may be inserted between these two parts.

[0029] For the description of temporal relationships, for example, when the temporal relationship is described as "after," "subsequently," "next," "before," etc., unless the term "immediately" or "directly" is used in the statement, non-consecutive cases may be included.

[0030] The features of the various embodiments of this specification may be partially or wholly combined or combined with each other. The embodiments may interact and be executed in various ways technically and may be performed independently or in association with each other.

[0031] Hereinafter, a display device and a driving method thereof according to an embodiment of this specification will be described with reference to the accompanying drawings.

[0032] Figure 1 is a block diagram of a display device according to an embodiment of this specification.

[0033] As Figure 1As shown, a display device according to an embodiment of the present invention includes an image supply circuit 110, a timing control circuit 120, a gate driver circuit 130, two data driver circuits 140-1 and 140-2, a display panel 150, and a power supply unit 400.

[0034] The image supply circuit 110 performs image processing on a data signal and outputs the processed data signal together with a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, a clock signal, etc. The image supply circuit 110 supplies the vertical synchronization signal, the horizontal synchronization signal, the data enable signal, the clock signal, the data signal DATA, etc. to the timing control circuit 120.

[0035] The timing control circuit 120 receives the data signal DATA, etc. from the image supply circuit 110 and outputs a gate timing control signal GDC for controlling the operation timing of the gate driver circuit 130 and a data timing control signal DDC for controlling the operation timing of the data driver circuits 140-1 and 140-2. The timing control circuit 120 supplies the data signal DATA together with the data timing control signal DDC to the two data driver circuits 140-1 and 140-2. The timing control circuit 120 may be referred to as a timing controller, and is not limited by its name as long as it performs the functions and operations as described above.

[0036] Meanwhile, on the control printed circuit board, various components or elements may be installed, which include the timing control circuit 120 that may be implemented in the form of an integrated circuit (IC) and a level shifter circuit (not shown), and conductive lines may be provided. The control printed circuit board may be connected to the source printed circuit board through a connection member.

[0037] The gate driver circuit 130 shifts the gate voltage level in response to the gate timing control signal GDC supplied from the timing control circuit 120 and outputs a gate signal. The gate driver circuit 130 includes a level shifter and a shift register.

[0038] The gate driver circuit 130 supplies the gate signal to the sub-pixels SP included in the display panel 150 through the gate lines GL1 to GLm. The gate driver circuit 130 may be formed on the display panel 150 in a gate-in-panel method or in the form of an IC. The part formed in the gate driver circuit 130 in the gate-in-panel method is a shift register.

[0039] The data driver circuits 140-1 and 140-2 sample and latch a data signal DATA in response to a data timing control signal DDC supplied from the timing control circuit 120, convert the digital signal into an analog signal corresponding to a gamma voltage, and output the converted analog signal. The data driver circuits 140-1 and 140-2 supply the data signal to the sub-pixels SP included in the display panel 150 through data lines DL1a to DLna and DL1b to DLnb. The data driver circuits 140-1 and 140-2 may be formed in the form of an IC.

[0040] Meanwhile, each source driver IC in the source driver ICs may be connected to the bonding pads of the display panel 150 by a tape automated bonding (TAB) method or a chip on glass (COG) method, or may be directly disposed on the display panel 150, or may be disposed by being integrated with the display panel 150. In addition, each source driver IC may be implemented by a chip on film (COF) method. In this case, one end of the film on which each source driver IC is mounted is bonded to at least one source printed circuit board, and the other end thereof is bonded to the display panel 150.

[0041] In a dual-group type display device, the data driver circuits 140-1 and 140-2 are disposed at two opposite edges of the display panel 150. In a dual-group type display device, the source driver ICs are distributed and disposed on one side and the other side of the display panel 150, that is, at two opposite edges of the display panel 150.

[0042] The display panel 150 displays an image in response to a gate signal and a data signal output from a driver circuit including the gate driver circuit 130 and the data driver circuits 140-1 and 140-2. Depending on the material of the substrate, the display panel 150 is implemented in a flat shape, a curved shape, a flexible shape, etc. The display panel 150 includes a display area defined by a plurality of pixels and a non-display area in which various signal lines or pads are formed. A plurality of pixels defined by a plurality of data lines DL1 to DLn and a plurality of gate lines GL1 to GLm are disposed in the display area of the display panel 150, and a plurality of sub-pixels SP are included in one pixel.

[0043] The sub-pixel SP includes a red sub-pixel, a green sub-pixel, and a blue sub-pixel, or includes a white sub-pixel, a red sub-pixel, a green sub-pixel, and a blue sub-pixel. Depending on the light emission characteristics, the sub-pixel SP may have one or more different light emission regions.

[0044] The display area is the area where an image is displayed, and a plurality of sub-pixels and circuits for driving the plurality of sub-pixels can be provided in the display area. Additionally, the display area can be divided into certain regions, and different images can be displayed for each region. For example, when the display panel 150 is a foldable display panel, the display area consists of two divided regions using the center of the folding region as a boundary line, such that different images can be displayed for each region.

[0045] The power supply unit 400 may include a charge pump, a regulator, a buck converter, a boost converter, a gamma voltage generation circuit, etc. The power supply unit 400 regulates the direct current (DC) input voltage supplied from the host system to generate the power required to drive the data driver circuits 140-1 and 140-2, the gate driver circuit 130, and the display panel 150. The power supply unit 400 may output DC voltages such as a gamma reference voltage, a gate cut-off voltage VGH / VEH, a gate on-voltage VGL / VEL, a pixel driving voltage (high potential power supply voltage) ELVDD, a cathode voltage (low potential power supply voltage) ELVSS, an initialization voltage Vini, and a reference voltage VREF.

[0046] The power supply unit 400 may also generate and output a data driver voltage SVDD and an IC power supply voltage SVCC, which are the power supplies for driving the source driver IC under the control of the timing control circuit 120.

[0047] Figure 2 FIG. is a diagram briefly showing the data line configuration of a display device according to an embodiment of the present specification.

[0048] Referring to Figure 2 , a display device according to an embodiment of the present specification may be a dual-group type display device, and the data driver circuits may be provided at two opposite edges of the display panel 150. In this case, the source driver ICs 10 and 20 are distributed and provided on one side and the other side of the display panel 150, that is, on two opposite edges of the display panel 150. In one embodiment, one side of the display panel 150 may be the upper end side, and the other side of the display panel 150 may be the lower end side. For ease of description, the source driver IC provided on the upper end side may be referred to as the first source driver IC 10, and the source driver IC provided on the lower end side may be referred to as the second source driver IC 20.

[0049] In one embodiment, the display area of the display panel 150 may include a first area R1 at the upper part on one side and a second area R2 at the lower part on the other side. The first area R1 at the upper part and the second area R2 at the lower part may be separated by a horizontal imaginary reference line BL that divides the display area. In one embodiment, the horizontal reference line BL may divide the display area into two halves, and each of the first area R1 and the second area R2 may correspond to an area that is half of the display area.

[0050] Data lines from the upper data driver circuit and data lines from the lower data driver circuit are simultaneously connected to one sub-pixel SP to simultaneously supply data output from one of the first source driver ICs 10 and data output from one of the second source driver ICs 20. In this way, the first source driver IC 10 and the second source driver IC 20 correspond to each other one-to-one, such that the output of one of the first source driver ICs 10 and the output of one of the second source driver ICs 20 are supplied to one pixel in the entire pixel array.

[0051] Figure 3A is a diagram illustrating a method of driving a display device according to an embodiment of the present specification.

[0052] In Figure 3A the image displayed in the display area may include a messenger screen displayed in the first area R1 as the upper part and a keyboard screen displayed in the second area R2 as the lower part. In one embodiment, the messenger screen in the first area R1 may have relatively large image changes, resulting in a large number of data transitions. On the other hand, the keyboard screen in the second area R2 may have relatively small image changes, resulting in a small number of data transitions. In this case, instead of performing dual-group driving, all of the second source driver ICs 20-1, 20-2, 20-3, 20-4, 20-5, 20-6 at the lower end may be turned off to perform single-group driving, thereby reducing power consumption.

[0053] In addition, in other cases, when the screen in the first area R1 has relatively small image changes resulting in a small number of data transitions, and the screen in the second area R2 has relatively large image changes resulting in a large number of data transitions, instead of Figure 3A as shown, turning off all of the second source driver ICs 20 at the lower end, all of the first source driver ICs 10 at the upper end may be turned off, and the source driver ICs at the lower end may be turned on, thereby enabling single-group driving. In one embodiment, the image changes may include changes in the gray level of the image, which may also be applied to the following description.

[0054] Figure 3B A method of driving a display device according to another embodiment of the present specification is shown.

[0055] In Figure 3B , similar to Figure 3A , the image displayed in the display area may include a messaging screen displayed in a first area R1 as an upper part and a keyboard screen displayed in a second area R2 as a lower part. In one embodiment, the messaging screen in the first area R1 and the keyboard screen in the second area R2 may not change significantly as a whole, and the keyboard screen in the second area R2 may change due to the touch of one of the keyboards, resulting in a large amount of data conversion. In this case, one source driver IC 20-4 of the second source driver IC 20 at the lower end and one source driver IC 10-4 of the first source driver IC 10 at the upper end, which are associated with a predetermined area including a part E where the display area has changed due to a touch event, remain in an on state and are driven in a double-group manner, and the remaining source driver ICs 20-1, 20-2, 20-3, 20-5, and 20-6 of the second source driver IC 20 at the lower end can be turned off to drive the remaining area except the above-mentioned predetermined area in a single-group manner, thereby reducing power consumption.

[0056] To assist Figure 3B in the intuitive understanding, the source driver ICs associated with a predetermined area including a part E where the display area has changed are determined to be the source driver ICs 10-4 and 20-4 placed on a vertical imaginary line L, but this is exemplary, and a specific determination method will be described below with reference to Figure 4 a specific determination method will be described below with reference to

[0057] Figure 3C is a diagram showing a method of driving a display device according to still another embodiment of the present specification.

[0058] In Figure 3C , the display area may include a third area R3 and a fourth area R4, and the third area R3 and the fourth area R4 have a boundary line connecting one side where the first source driver IC 10 is provided and the other side where the second source driver IC 20 is provided, that is, an area divided in the horizontal direction, as Figure 3CAs shown, as an image displayed in the display area, a screen with a solid color pattern can be displayed in the third area R3 on the left, and a screen including an active pattern with a dynamically changing image can be displayed in the fourth area R4 on the right. In one embodiment, the screen in the third area R3 displays a solid color pattern with little image change, resulting in a small number of data transitions. On the other hand, the screen in the fourth area R4 displays an active pattern with relatively large image changes, resulting in a large number of data transitions. In this case, the first source driver ICs 10-4, 10-5, 10-6 and the second source driver ICs 20-4, 20-5, 20-6 associated with the fourth area R4 can be continuously maintained in the on state and perform dual-group driving on the fourth area R4, and the second source driver ICs 20-1, 20-2, 20-3 associated with the third area R3 can be controlled to be off and perform single-group driving on the third area R3, thereby reducing current consumption.

[0059] Each source driver IC among the source driver IC associated with the third area R3 and the source driver IC associated with the fourth area R4 is determined as the source driver IC set in the corresponding area to help intuitive understanding, as Figure 3B shown, but this is exemplary, and the specific determination method will be described below.

[0060] Figure 4 is a diagram conceptually showing a method for detecting whether a data transition has occurred according to an embodiment of the present specification.

[0061] A method for driving a display device according to an embodiment of the present specification may include: receiving pixel data of an input image; storing the pixel data in a memory; comparing the change amount between the Nth row data (N is a natural number) stored in the memory and the (N + 1)th row data with a preset reference value; when the change amount between the Nth row data and the (N + 1)th row data is greater than or equal to the reference value, sequentially transmitting the Nth row data and the (N + 1)th row data to the source driver IC, and when the change amount between the Nth row data and the (N + 1)th row data is less than the reference value, cutting off the driving power of the source driver IC.

[0062] In addition, the Nth row data may include pixel data of pixels of the Nth pixel row written to the display panel, and the (N + 1)th row data may include pixel data of pixels of the (N + 1)th pixel row written to the display panel. In short, the pixel data of pixels written to the Nth pixel row (i.e., the Nth pixel row) and the (N + 1)th pixel row (i.e., the next pixel row of the Nth pixel row) may be the Nth row data and the (N + 1)th row data.

[0063] Referring to Figure 4More specifically described, by receiving pixel data of an input image, detecting the amount of data change between row data, i.e., the degree of data transition, and by determining and classifying whether the row of corresponding pixels corresponds to a first region R1 at the upper part of the screen or a second region R2 at the lower part of the screen, and comparing the amount of change between the row data in each region with a preset reference value, when the amount of change between the row data is less than the set reference value, the driving power of the corresponding source driver IC is cut off.

[0064] In one embodiment, associated with the arrangement form of the source driver IC as shown in Figures 3A to 3C The pixels receiving the output of each source driver IC can be pixels included in a region having a uniform predetermined width. In other words, when considering Figures 3A to 3C the arrangement form of the source driver IC shown in Figure 3C Six regions having a uniform width in the horizontal direction can be assumed in the same way, and the pixels in each region can receive the output from the corresponding source driver IC.

[0065] In this way, the source driver IC can correspond to the pixels in a predetermined region separated in the horizontal direction respectively, and by classifying whether the pixel row corresponds to the upper region or the lower region of the screen when detecting the amount of data change between the row data, the driving power of the source driver IC can be selectively cut off. An enable signal such as SD_IC1_EN_TOP is applied to the switching circuit corresponding to the source driver IC determined to continue driving to supply the data driver voltage SVDD and the IC power supply voltage SVCC, and the data driver voltage SVDD and the IC power supply voltage SVCC can be cut off by controlling the switching circuit corresponding to the source driver IC determined to cut off the driving power with the enable signal.

[0066] In one embodiment of the present specification, a plurality of source driver ICs are provided on each of the opposite sides of the display panel, and the source driver IC whose driving power is cut off can be one of the plurality of source driver ICs provided on one of the sides.

[0067] Referring again to Figure 3A , the transceiver screen in the first region R1 has a relatively large image change, resulting in a large occurrence of data transition, and the keyboard screen in the second region R2 has a relatively small image change, resulting in a small occurrence of data transition. In this case, instead of dual-group driving, single-group driving can also be performed in a state where the driving power of all the second source driver ICs 20 is cut off. For example, as shown in Figure 3ADifferently, when the screen in the first region R1 has relatively small image changes, resulting in a small number of data transitions, and the screen in the second region R2 has relatively large image changes, resulting in a large number of data transitions, single-group driving can be performed instead of double-group driving. In this case, the display panel is driven in a state where the driving power of all the first source driver ICs 10 is cut off. Therefore, power consumption can be reduced.

[0068] In one embodiment of the present specification, a plurality of source driver ICs are provided on each of the opposite sides of the display panel. The source driver IC whose driving power is cut off can be some of the plurality of source driver ICs provided on one of the sides.

[0069] Referring again to Figure 3B , the messaging screen in the first region R1 and the keyboard screen in the second region R2 may remain unchanged as a whole, and the keyboard screen in the second region R2 may change due to the touch of one of the keyboards, resulting in a large number of data transitions. In this case, the first source driver IC 10-4 and the second source driver IC 20-4 associated with the pixels where a large number of data transitions occur (such as the part E where the display area changes due to a touch event, etc.) can be continuously kept in the on state and thus driven in a double-group manner, and among the first source driver ICs 10-1, 10-2, 10-3, 10-5, and 10-6 and the second source driver ICs 20-1, 20-2, 20-3, 20-5, and 20-6 associated with the remaining pixels where no data transitions are generated, the supply of the driving power to the second source driver ICs 20-1, 20-2, 20-3, 20-5, and 20-6 can be cut off. Therefore, power consumption can be reduced.

[0070] In addition, referring again to Figure 3C, the screen display image in the third region R3 shows a solid color pattern with very little change, resulting in a small amount of data transition, while the screen display image in the fourth region R4 shows an active pattern with relatively large changes, resulting in a large amount of data transition. In this case, the first source driver ICs 10-4, 10-5, 10-6 and the second source driver ICs 20-4, 20-5, 20-6 associated with the pixels with a large amount of data transition in the fourth region R4 can be continuously maintained in the on state and can be driven in a double-group manner. And in the first source driver ICs 10-1, 10-2, 10-3 and the second source driver ICs 20-1, 20-2, 20-3 associated with the remaining pixels in the third region R3 where no data transition occurs, the supply of the driving power of the second source driver ICs 20-1, 20-2, 20-3 can be cut off. Therefore, the current consumption can be reduced.

[0071] Figure 5 is a diagram showing a method of setting blocks when detecting whether a data transition has occurred according to an embodiment of the present specification.

[0072] In an embodiment of the present specification, in a method of comparing the change amount between row data with a preset reference value, the pixels of a display panel that respectively receive the outputs from a plurality of source driver ICs can be set as blocks pixel by pixel row, and the change amount between row data can be compared with the preset reference value for each set block. In addition, when the change amount between row data is lower than the preset reference value for all the set blocks, the driving power of the source driver IC can be cut off.

[0073] As described above, since the pixels in a predetermined region and the source driver IC correspond to each other, the corresponding source driver IC can be controlled by comparing the change amount between the row data of the pixels in one region with a preset reference value.

[0074] More specifically, blocks are set for the pixels on the pixel rows in the pixels for which each source driver IC is responsible for supplying data. Figure 5 is a table showing an exemplary block setting situation related to the number of pixels. In one embodiment, blocks can be set such that each block includes the same number of pixels as the pixels on the pixel rows in the pixels for which each source driver IC is responsible for supplying data. For the sake of understanding, refer to Figure 5 For description, the number of pixels on the pixel rows in the pixels for which each source driver IC is responsible for supplying data can be 443. The blocks can be set in such a way that each block includes the same number of pixels among the 443 pixels.

[0075] Refer to Figure 5, the more the number of blocks is set (i.e., the closer to Option 1), the more accurate the comparison and determination of the change amount between row data and the preset reference value are, but the efficiency decreases. On the contrary, the fewer the number of blocks is set (i.e., the closer to Option 7), the higher the efficiency of comparing and determining the change amount is, but the accuracy decreases. Therefore, the number of blocks can be appropriately set and utilized according to needs.

[0076] After setting the blocks, the change amount between row data is calculated for each block. When the change amounts calculated for all blocks are less than the preset reference value, the driving power of the corresponding source driver IC can be cut off. In one embodiment, the preset reference value can be 60%. In this case, for all blocks, pixels that satisfy the condition that the change amount between row data is less than 60% can be determined as not having data transition, and the driving power of the corresponding source driver IC can be cut off.

[0077] Figures 6A to 6C is a diagram for describing a method of using a lookup table (LUT) when detecting whether data transition has occurred according to an embodiment of the present specification.

[0078] In one embodiment of the present specification, in the method of comparing the change amount between row data with the preset reference value, the change amount between the Nth row data and the (N + 1)th row data can be compared with a lookup table. Additionally, when there is no value corresponding to the change amount between the Nth row data and the (N + 1)th row data in the lookup table, the driving power of the source driver IC can be cut off.

[0079] In one embodiment, data slew can be considered and a value used in a series of processes of calculating the change amount by comparing the amplitudes between row data and comparing the change amount with the value in the preset lookup table can be measured or calculated based on data slew.

[0080] Refer to Figure 6A , in the measurement of data slew according to an embodiment, when assuming single-group driving, there is no difference in uniformity at the near point NP close to the source driver IC 10, but the uniformity significantly decreases at the far point FP far from the source driver IC 10. Therefore, the data value can be measured based on the data slew at the center point CP - the center point CP can be considered to have almost no change in uniformity - and the data value can be used to detect the change amount between row data. In an exemplary embodiment, when the change amount between row data reaches 98%, the data slew at the center point CP can be 2.461 us for the rising edge and 2.313 us for the falling edge.

[0081] Refer to Figure 6B, it is possible to confirm the difference in the rising edge of the data slope between the near point NP and the far point FP from the source driver IC 10, and the time when the change amount between the data reaches 98% is T1 at the near point NP and T2 at the far point FP, where T1 < T2, indicating that the time when the change amount between the data reaches 98% is later at the far point FP than at the near point NP. Additionally, a similar phenomenon occurs at the falling edge.

[0082] Figure 6C is a diagram for describing an exemplary method of setting a lookup table. The specific method of setting the lookup table is as follows, which corresponds to one embodiment of setting the lookup table.

[0083] Refer again to Figure 6A , and measure the maximum data change amount at each of the near point NP and the far point FP of the input data. Here, the maximum data change amount refers to the maximum value among the data change amounts when the gray level changes from black to white or from white to black.

[0084] Figure 6B The data slew graph is used to determine the pixel rows having a data change amount greater than or equal to a preset reference value. In one embodiment, the preset reference value can be 60%, and the corresponding time can be 2.64 us. The pixel rows determined in this way are set as the Xth row, as Figure 6A shown. As a reference, the point corresponding to the reference value of 60% can correspond to 60% of the time of one horizontal period (1H).

[0085] All gray level values having a data slope greater than or equal to 60% in the data rows from the Xth row of the far point FP to the end row can be stored in the lookup table. More specifically, when the change amount between the data is higher than the preset reference value, the gray level values can be stored in the lookup table based on the voltage difference, and in the case of the Xth row, the voltage difference between black and white can be used as a reference. Starting from the X + 1th row, all gray level values with voltages greater than or equal to the voltage difference when the data slope is 60% or more can be stored in the lookup table. For example, assuming that the gray level change with a data slope of 60% at the far point FP is from 0 to 200, and assuming that the gray level 0 is 5V and the gray level 200 is 3V, then the voltage difference is 2V, so the lookup table can be set in such a way that all pairs of gray level values with a voltage difference of 2V or more are stored in the lookup table. This can be further understood with reference to Figure 6C the table of

[0086] When using a lookup table to compare the variation between row data with a preset reference value, in a control method of a source driver IC according to another embodiment of the present specification, when it is determined based on the near point NP that the pixel row for which the variation is to be measured corresponds to a row above the X-th row, the variation between the row data based on the data slope is compared with a preset lookup table to determine whether the variation is greater than a preset reference value (e.g., 60%), and when the variation does not exist in the lookup table, the source driver IC on the far point FP side can be completely turned off. Additionally, when it is determined based on the far point FP that the pixel row for which the variation is to be measured corresponds to a row below the X-th row, the variation between the row data based on the data slope is compared with a preset lookup table to determine whether the variation is greater than a preset reference value (e.g., 60%), and when the variation does not exist in the lookup table, the source driver IC on the near point NP side can be completely turned off. Finally, when the pixel row for which the variation is to be measured is not above and below the X-th row based on the near point NP and the far point FP, it is indicated that the pixel row for which the data variation is to be compared is near the center point CP. In this case, a determination of whether to cut off the driving power of the source driver IC may not be made.

[0087] In the description of the above control method of the source driver IC according to another embodiment of the present specification, the terms "near point NP" and "far point FP" are used for the convenience of understanding the description related to the X-th row after the description of Figures 6A to 6C and should not be construed as limiting the source driver IC to be only provided on one side of the display panel, and since the source driver IC can be provided on each of the facing sides and the other side of the display panel as Figures 3A to 3C shown, the terms "near point NP" and "far point FP" herein should be construed as representing one side and the other side of the display panel.

[0088] Figure 7 is a diagram briefly showing a switch circuit configured to control the source driver IC according to an embodiment of the present specification, and Figure 8 is a diagram showing in more detail Figure 7 the switch circuit of

[0089] As described above with reference to Figure 1 the source driver IC can be mounted on a film, one end of the film can be connected to the source printed circuit board SPCB, and the other end thereof can be connected to the display panel 150. Additionally, the control printed circuit board CPCB can generate a control signal for selecting the driving of the source driver IC and supply the control signal to the source printed circuit board SPCB.

[0090] Figure 7The structure of the source printed circuit board SPCB on one side of the display panel is briefly shown. Referring to this, the on and off of the source driver IC 10 can be controlled by the switching circuits SW1 to SW6 implemented on the source printed circuit board SPCB. The switching circuits SW1 to SW6 can control the supply of the data driver voltage SVDD and the IC power supply voltage SVCC to the source driver IC 10. The data driver voltage SVDD is an analog voltage of the source printed circuit board SPCB, which is generated in the control printed circuit board CPCB and provided to the source printed circuit board SPCB through the connector CNT. And the IC power supply voltage SVCC is a logic voltage of the source printed circuit board SPCB. Once it is determined through the above process which source driver IC is to be turned off, the source driver IC is controlled to turn off by turning off the data driver voltage SVDD and the IC power supply voltage SVCC supplied to the determined source driver IC to be turned off.

[0091] Each of the switching circuits SW1 to SW6 can be individually controlled by the enable signals SD-IC1_EN to SD-IC6_EN generated in the control printed circuit board CPCB and transmitted to the source printed circuit board SPCB, so as to selectively cut off the driving power of the source driver IC 10.

[0092] Figure 8 Exemplarily shown in more detail Figure 7 the switching circuit. Referring to this, the control printed circuit board CPCB can generate the enable signals SD-IC1_EN to SD-IC6_EN for individually controlling the data driver voltage SVDD, the IC power supply voltage SVCC, and the switching circuit, and transmit the enable signals SD-IC1_EN to SD-IC6_EN to the source printed circuit board SPCB. The source printed circuit board SPCB individually controls the switching circuit for turning on and off each source driver IC by using each of the enable signals SD-IC1_EN to SD-IC6_EN, so as to apply or block the data driver voltage SVDD and the IC power supply voltage SVCC to each source driver IC. Therefore, the source driver IC can be selectively turned on and off.

[0093] Figure 9A and Figure 9B are diagrams showing an exemplary case where the method of driving a display device according to an embodiment of the present specification is applied to a display device.

[0094] In one embodiment, the display device may be a foldable display device, and may be held in a folded state at a specific angle, or may be fully folded or unfolded. The display panel may be flexible so as to be folded and unfolded as the foldable display device is folded and unfolded. Additionally, the foldable display device may be an inward-fold type, in which the display device is folded or unfolded such that the display panel is disposed inside, and may be an outward-fold type, in which the display device is folded or unfolded such that the display panel is disposed outside.

[0095] When the foldable display device is driven in the folded state, different images are generally used for one side of the display area and the other side of the display area by the display areas separated by the fold. When different images are displayed in different areas, data transitions may occur in relatively small areas, and by turning off the source driver IC associated with the corresponding area, current consumption can be reduced.

[0096] In Figure 9A , when the foldable display device is driven in an outward-folded manner, current consumption of the lower display area facing downward and not being displayed can be reduced by turning off the associated source driver IC. Additionally, in Figure 9B , when the foldable display device is in a split-screen operation, the upper display area is used for video viewing and the lower display area is used for chatting, and the source driver IC associated with the lower display area with little image change can be turned off to reduce current consumption.

[0097] As described above, in the display device and its driving method according to an embodiment of the present specification, the advantage of reducing current consumption is achieved by: in a dual-group type display device, driving the display area, and detecting whether a data transition has occurred in the pixels corresponding to the source driver ICs respectively and turning off the corresponding source driver ICs, and also selectively driving the source driver ICs according to the type of the images separately driven on the display panel, such as driving the entire area in a single-group type or only driving a part of the area in a single-group type.

[0098] According to an embodiment of the present specification, in a dual-group type display, the display area is separated, and data transitions can be detected for the pixels corresponding to the source driver integrated circuits (ICs) respectively to perform single-group driving in which the corresponding source driver ICs are turned off, thereby reducing current consumption and achieving low-power driving.

[0099] According to an embodiment of the present specification, current consumption can be reduced by selectively driving the source driver ICs, such as driving the entire display panel in a single-group type or only driving some areas of the display panel in a single-group type according to the type of the images separately displayed by area on the display panel.

[0100] According to an embodiment of the present specification, by setting pixels corresponding to a source driver IC as blocks for each pixel row and detecting whether there is a data transition for each block, the detection efficiency can be improved while allowing customization in terms of accuracy.

[0101] According to an embodiment of the present specification, by using a preset look-up table based on data slope to detect whether a data transition has occurred, more accurate detection can be achieved.

[0102] The effects of the present specification are not limited to the above effects, and those skilled in the art can clearly understand other effects not mentioned from the following description.

[0103] Although the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various changes and modifications can be made without departing from the technical gist of the present invention. Therefore, the embodiments disclosed herein are considered to be descriptive rather than restrictive of the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, the above embodiments should be understood as exemplary and not restrictive in any way. The scope of the present invention should be interpreted by the appended claims, and all technical spirits within the scope of equivalents of the appended claims should be interpreted as being included within the scope of the present invention.

Claims

1. A method for driving a display device, the method comprising: Receiving pixel data of an input image; storing the pixel data in a memory; Comparing the change between the Nth row of data and the N+1th row of data stored in the memory with a preset reference value, where N is a natural number; When the variation between the Nth row of data and the N+1th row of data is greater than or equal to the preset reference value, sequentially transmitting the Nth row of data and the N+1th row of data to the source driver integrated circuit; as well as When the variation between the Nth row of data and the N+1th row of data is less than the preset reference value, the driving power of the source driver integrated circuit is cut off, The Nth row of data includes pixel data of pixels in the Nth pixel row written to the display panel, and The N+1th row of data includes pixel data written to pixels in the N+1th pixel row of the display panel.

2. The method according to claim 1, wherein: A plurality of source driver integrated circuits are provided on each of one side and the other side facing each other on the display panel, and Wherein, cutting off the driving power of the source driver integrated circuit includes: cutting off the driving power of the plurality of source driver integrated circuits arranged on one of the one side and the other side.

3. The method according to claim 2, wherein: The display area of ​​the display panel is divided into a first area on the one side and a second area on the other side, and Different images are displayed in the first area and the second area respectively.

4. The method according to claim 1, wherein: A plurality of source driver integrated circuits are arranged on the display panel. Wherein, comparing the change amount between the Nth row of data and the N+1th row of data with the preset reference value includes: arranging a pixel group of the display panel receiving an output from one of the plurality of source driver integrated circuits into blocks by each of the pixel rows of the pixel group; and The variation between the row data of each block in the set blocks is compared with the preset reference value, and When the variation between the row data of all the set blocks is smaller than the preset reference value, the driving power of the source driver integrated circuit is cut off.

5. The method according to claim 1, wherein: Comparing the change between the Nth row of data and the N+1th row of data with the preset reference value includes: comparing the change between the Nth row of data and the N+1th row of data with a preset lookup table, and When there is no value corresponding to the change between the Nth row of data and the N+1th row of data in the lookup table, the driving power of the source driver integrated circuit is cut off.

6. A display device comprising: A display panel having a plurality of data lines, a plurality of gate lines and a plurality of pixels arranged thereon; a plurality of source driver integrated circuits configured to convert received pixel data into data voltages and supply the data voltages to the data lines; a timing controller configured to receive an input image and transmit the pixel data to the source driver integrated circuit; as well as a power supply unit configured to output power for driving the source driver integrated circuit under the control of the timing controller; Wherein, the timing controller is configured as follows: Storing pixel data of the input image in a memory; Comparing the change between the Nth row of data and the N+1th row of data stored in the memory with a preset reference value, where N is a natural number; When the variation between the Nth row of data and the N+1th row of data is greater than or equal to the preset reference value, sequentially transmitting the Nth row of data and the N+1th row of data to the source driver integrated circuit; and When the variation between the Nth row data and the N+1th row data is smaller than the preset reference value, the power supply unit is controlled and the driving power of the source driver integrated circuit is cut off.

7. The display device according to claim 6, wherein: The plurality of source driver integrated circuits are disposed on each of one side and the other side of the display panel facing each other, and The source driver integrated circuit whose driving power is cut off is the plurality of source driver integrated circuits arranged on one of the one side and the other side.

8. The display device according to claim 7, wherein: The display area of ​​the display panel is divided into a first area on the one side and a second area on the other side, and Different images are displayed in the first area and the second area respectively.

9. The display device according to claim 6, wherein: The change between the Nth row of data and the N+1th row of data is compared with the preset reference value by: arranging a pixel group of the display panel receiving an output from one of the plurality of source driver integrated circuits into a block by each of the pixel rows of the pixel group; as well as The variation between the row data of each block in the set blocks is compared with the preset reference value, and When the variation between the row data of all the set blocks is smaller than the preset reference value, the driving power of the source driver integrated circuit is cut off.

10. The display device according to claim 6, wherein: By comparing the change amount between the Nth row of data and the N+1th row of data with a preset lookup table, the change amount between the Nth row of data and the N+1th row of data is compared with the preset reference value, and When there is no value corresponding to the change between the Nth row of data and the N+1th row of data in the lookup table, the driving power of the source driver integrated circuit is cut off.

Images