Display device and method of operating the same

Abstract

Embodiments of the present inventive concept relate to a display device and a method for operating the display device, the display device including: a display panel including a plurality of pixels; a data driver providing data signals to the plurality of pixels; and a controller controlling the data driver. The controller writes frame data into a frame memory, reads the frame data in each of a plurality of frame periods, performs a still image detection operation to determine whether the frame data represents a still image in a first frame period among the plurality of frame periods, and does not perform the still image detection operation in a second frame period after the first frame period among the plurality of frame periods.

Description

Technical Field

[0001] Embodiments of the inventive concept relate to a display device, and more particularly, to a display device that performs adaptive refresh and a method of operating the display device. Background Art

[0002] For example, in display devices used in portable devices such as smartphones and tablet computers, it is desirable to reduce power consumption to extend battery life. To reduce power consumption of display devices, low-frequency driving technologies (e.g., adaptive refresh technology or adaptive refresh panel (ARP) technology) have been developed. Low-frequency driving technologies drive or refresh a display panel at a frequency lower than a normal driving frequency by analyzing image data. Summary of the Invention

[0003] In a mode where an input frame frequency is lower than a driving frequency for a display panel (eg, a command mode of a Mobile Industry Processor Interface ("MIPI")), the low-frequency driving technology or the ARP technology may not be effectively performed.

[0004] Some embodiments provide a display device capable of efficiently performing adaptive refresh panel ("ARP") technology.

[0005] Some embodiments provide a method of operating a display device capable of effectively performing an ARP technique.

[0006] According to an embodiment, a display device is provided, comprising: a display panel including a plurality of pixels; a data driver for providing data signals to the plurality of pixels; and a controller for controlling the data driver. The controller writes frame data to a frame memory, reads the frame data in each of a plurality of frame periods, performs a still image detection operation to determine whether the frame data represents a still image in a first frame period among the plurality of frame periods, and does not perform the still image detection operation in a second frame period after the first frame period among the plurality of frame periods.

[0007] In an embodiment, during the first frame period, the controller may selectively perform a driving frequency determination operation for determining a driving frequency for the display panel by analyzing the frame data based on a result of the still image detection operation. During the second frame period, the controller may perform the driving frequency determination operation without performing the still image detection operation.

[0008] In an embodiment, the controller may include: a receiving module that receives the frame data; a frame memory that stores the frame data; and an adaptive refresh panel module. In a first mode, during each frame period, and in a second mode, during the first frame period, the adaptive refresh panel module may perform the still image detection operation on the frame data and, based on a result of the still image detection operation, selectively perform a driving frequency determination operation to determine a driving frequency for the display panel by analyzing the frame data. In the second mode, during the second frame period, the adaptive refresh panel module may not perform the still image detection operation on the frame data and may perform the driving frequency determination operation on the frame data.

[0009] In an embodiment, in the first mode, the receiving module may receive the frame data at a first frame frequency and may not write the frame data to the frame memory. In the first mode, the adaptive refresh panel module may receive the frame data directly from the receiving module at the first frame frequency. In the second mode, the receiving module may receive the frame data at a second frame frequency lower than the first frame frequency and may write the frame data to the frame memory at the second frame frequency. In the second mode, the adaptive refresh panel module may read the frame data from the frame memory at the first frame frequency.

[0010] In an embodiment, the first mode may be a video mode and the second mode may be a command mode.

[0011] In an embodiment, the controller may further include: a still image detection flag module, which generates a still image detection flag signal having a first logic level in each frame period in the first mode and in the first frame period in the second mode, and generates the still image detection flag signal having a second logic level in the second frame period in the second mode.

[0012] In an embodiment, the adaptive refresh panel module may perform the still image detection operation on the frame data in response to the still image detection flag signal having the first logic level, and may not perform the still image detection operation on the frame data in response to the still image detection flag signal having the second logic level.

[0013] In an embodiment, the adaptive refresh panel module may include: a still image detection module, which, in response to the still image detection flag signal having the first logic level, performs the still image detection operation of determining whether the frame data represents the still image by comparing the frame data in the current frame period and the frame data in the previous frame period, and generates a still flag signal having the first logic level when the frame data represents the still image; and a driving frequency determination module, which, in response to the still image detection flag signal having the second logic level or the still flag signal having the first logic level, performs the driving frequency determination operation of determining the driving frequency for the display panel by analyzing the frame data.

[0014] In an embodiment, the driving frequency decision module may not perform the driving frequency decision operation in response to the still image detection flag signal having the first logic level and the still flag signal having the second logic level.

[0015] In an embodiment, when the frame data in the current frame period is substantially the same as the frame data in the previous frame period, the still image detection module may generate the still flag signal having the first logic level, and when the frame data in the current frame period is different from the frame data in the previous frame period, the still image detection module may generate the still flag signal having the second logic level.

[0016] In an embodiment, when the still image detection flag signal has the first logic level and the still flag signal has the second logic level, the driving frequency determination module may provide the frame data to the data driver without performing the driving frequency determination operation. When the still image detection flag signal has the second logic level or the still flag signal has the first logic level, the driving frequency determination module may selectively provide the frame data to the data driver according to the driving frequency determined by the driving frequency determination operation.

[0017] In an embodiment, the driving frequency determination module may include: a flicker lookup table, which stores flicker values ​​corresponding to grayscale levels; a segment division module, which divides the frame data into multiple segment data respectively used for multiple segments; a segment frequency determination module, which determines multiple segment flicker values ​​corresponding to the grayscale levels of the multiple segment data by using the flicker lookup table, and determines multiple segment frequencies respectively used for the multiple segments according to the multiple segment flicker values; and a maximum frequency determination module, which determines the maximum segment frequency of the multiple segment frequencies as the driving frequency for the display panel.

[0018] In an embodiment, the still image detection flag module may provide frame repetition number information to the adaptive refresh panel module, where the frame repetition number information represents the number of the plurality of frame periods for reading the same frame data from the frame memory in the second mode.

[0019] In an embodiment, when providing the frame repetition number information to the adaptive refresh panel module, the still image detection flag module may provide the still image detection flag signal to the adaptive refresh panel module, and the still image detection flag signal includes a number of pulses corresponding to the number of the multiple frame periods.

[0020] In an embodiment, the driving frequency determination module may include: a flicker lookup table, which stores flicker values ​​corresponding to grayscale levels; a segment division module, which divides the frame data into multiple segment data respectively used for multiple segments; a segment frequency determination module, which determines multiple segment flicker values ​​corresponding to the grayscale levels of the multiple segment data by using the flicker lookup table, and determines multiple segment frequencies respectively used for the multiple segments according to the multiple segment flicker values; a maximum frequency determination module, which determines the maximum segment frequency among the multiple segment frequencies; and a final frequency determination module, which determines the driving frequency for the display panel based on the frame repetition number information and the maximum segment frequency.

[0021] In an embodiment, the final frequency determination module may determine the frame change frequency by dividing the normal driving frequency by the number of the plurality of frame periods represented by the frame repetition number information, and may determine the higher frequency between the maximum segment frequency and the frame change frequency as the driving frequency for the display panel.

[0022] In an embodiment, the adaptive refresh panel module may further include: a driving frequency mixing module, which gradually changes the driving frequency used for the display panel from the previous driving frequency to the current driving frequency when the current driving frequency determined by the driving frequency determination operation is different from the previous driving frequency used for the display panel.

[0023] According to an embodiment, a display device is provided, comprising: a display panel including a plurality of pixels; a data driver providing data signals to the plurality of pixels; and a controller controlling the data driver. The controller comprises: a frame memory; a receiving module receiving frame data at a first frame frequency in a first mode, receiving the frame data at a second frame frequency lower than the first frame frequency in a second mode, and writing the frame data to the frame memory at the second frame frequency in the second mode; and an adaptive refresh panel module receiving the frame data from the receiving module at the first frame frequency in the first mode and reading the frame data from the frame memory at the first frame frequency in the second mode, performing a still image detection operation to determine whether the frame data represents a still image in each frame period in the first mode and in a first frame period among a plurality of frame periods in the second mode, and not performing the still image detection operation on the frame data in a second frame period after the first frame period among the plurality of frame periods in the second mode.

[0024] In an embodiment, in each frame period in the first mode and in the first frame period in the second mode, the adaptive refresh panel module may selectively perform a driving frequency determination operation for determining a driving frequency for the display panel by analyzing the frame data according to a result of the still image detection operation. In the second frame period in the second mode, the adaptive refresh panel module may perform the driving frequency determination operation without performing the still image detection operation.

[0025] According to an embodiment, a method for operating a display device is provided. In the method, in a first mode, frame data is received at a first frame frequency; in the first mode, a still image detection operation is performed to determine whether the frame data represents a still image; in the first mode, a driving frequency determination operation is selectively performed to determine a driving frequency for a display panel by analyzing the frame data based on a result of the still image detection operation; in a second mode, the frame data is received at a second frame frequency lower than the first frame frequency; in the second mode, the frame data is written to a frame memory at the second frame frequency; in the second mode, the frame data is read from the frame memory at the first frame frequency; in the second mode, the still image detection operation is performed on the frame data read from the frame memory in a first frame period among a plurality of frame periods; in the second mode, the driving frequency determination operation is selectively performed in the first frame period based on a result of the still image detection operation; and in the second mode, the driving frequency determination operation is performed without performing the still image detection operation in a second frame period after the first frame period among the plurality of frame periods.

[0026] As described above, in a display device and a method for operating a display device according to an embodiment, frame data may be written to a frame memory, frame data may be read from the frame memory in each of a plurality of frame periods, a still image detection operation for determining whether the frame data represents a still image may be performed in a first frame period among the plurality of frame periods, and a still image detection operation for the frame data may not be performed in a second frame period after the first frame period among the plurality of frame periods. Therefore, unnecessary still image detection operations may not be performed, and an adaptive refresh panel ("ARP") technology may be performed more efficiently. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Illustrative, non-limiting embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

[0028] Figure 1 is a block diagram illustrating a display device according to an embodiment.

[0029] Figure 2 is a diagram showing an example of frame data in the first mode.

[0030] Figure 3 is a diagram showing an example of frame data in the second mode.

[0031] Figure 4 is a diagram showing an example of a still image detection signal in the first mode.

[0032] Figure 5is a diagram showing an example of a still image detection signal in the second mode.

[0033] Figure 6 is a block diagram illustrating an adaptive refresh panel module included in a display device according to an embodiment.

[0034] Figure 7 is a block diagram illustrating a driving frequency decision module included in a display device according to another embodiment.

[0035] Figure 8 is a diagram illustrating an example of a flicker lookup table included in a display device according to an embodiment.

[0036] Figure 9 is a diagram for describing an example of an operation of a segment division module included in a display device according to an embodiment.

[0037] Figure 10 is a diagram for describing an example of an operation of a segment frequency decision module included in a display device according to an embodiment.

[0038] Figure 11 is a block diagram illustrating an adaptive refresh panel module included in a display device according to an embodiment.

[0039] Figure 12 is a diagram for describing an example of an operation of a driving frequency mixing module included in a display device according to an embodiment.

[0040] Figure 13 is a block diagram illustrating a driving frequency decision module included in a display device according to an embodiment.

[0041] Figure 14 is a diagram showing an example of a still image detection signal in the display device according to the embodiment.

[0042] Figure 15 is a flowchart illustrating a method of operating a display device according to an embodiment.

[0043] Figure 16 An electronic device including a display device according to an embodiment. DETAILED DESCRIPTION

[0044] Hereinafter, the embodiment of the present invention will be explained in detail with reference to the accompanying drawings. It will be understood that although the terms "first", "second", "third" etc. can be used to describe various elements, components, regions, layers and / or parts in this article, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish an element, component, region, layer or part from another element, component, region, layer or part. Thus, without departing from the teachings herein, the first "element", "component", "region", "layer" or "part" discussed below can be referred to as the second element, component, region, layer or part. The terms used in this article are only for the purpose of describing a specific embodiment and are not intended to be restrictive. Unless the context clearly indicates otherwise, the singular forms "one", "one (kind)" and "the (said)" as used in this article are intended to include the plural form comprising "at least one". "At least one (said)" will not be interpreted as a restrictive "one" or "one (kind)". "Or" means "and / or". As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be further understood that when used in this specification, the terms "comprises and / or compriing" or "includes and / or including" specify the presence of stated features, regions, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and / or groups thereof.

[0045] Figure 1 is a block diagram showing a display device according to an embodiment, Figure 2 is a diagram showing an example of frame data in the first mode, Figure 3 is a diagram showing an example of frame data in the second mode, Figure 4 is a diagram showing an example of a still image detection signal in the first mode, and Figure 5 is a diagram showing an example of a still image detection signal in the second mode.

[0046] refer to Figure 1 According to an embodiment, the display device 100 may include: a display panel 110, the display panel 110 including a plurality of pixels PX; a data driver 120, the data driver 120 providing a data signal DS to the plurality of pixels PX; a scan driver 130, the scan driver 130 providing a scan signal SS to the plurality of pixels PX; and a controller 140, the controller 140 controlling the data driver 120 and the scan driver 130.

[0047] The display panel 110 may include a plurality of data lines, a plurality of scan lines, and a plurality of pixels PX, and the plurality of pixels PX are coupled to the plurality of data lines and the plurality of scan lines. In some embodiments, each pixel PX may include at least one capacitor, at least two transistors, and an organic light emitting diode ("OLED"), and the display panel 110 may be an OLED display panel. In addition, in some embodiments, each pixel PX may be a hybrid pixel suitable for low-frequency driving to reduce power consumption. For example, in the hybrid pixel, the drive transistor may be implemented with a low-temperature polysilicon ("LTPS") PMOS transistor, and the switch transistor may be implemented with an oxide NMOS transistor. In other embodiments, the display panel 110 may be a liquid crystal display ("LCD") panel or any other suitable display panel.

[0048] The data driver 120 may generate a data signal DS based on the frame data FDAT and the data control signal DCTRL received from the controller 140, and may provide the data signal DS to the plurality of pixels PX via a plurality of data lines. In some embodiments, the data driver 120 may receive the frame data FDAT from the controller 140 (particularly, the adaptive refresh panel module 180) at a first frame frequency FF1 (e.g., a normal driving frequency), or may receive the frame data FDAT from the controller 140 (particularly, the adaptive refresh panel module 180) at a driving frequency DF determined by a driving frequency determination operation of the adaptive refresh panel module 180. The driving frequency DF determined by the driving frequency determination operation may be lower than the first frame frequency FF1 (e.g., a normal driving frequency), and thus, when driven at the driving frequency DF rather than the first frame frequency FF1, power consumption of the display device 100 may be reduced. In addition, in some embodiments, the data control signal DCTRL may include, but is not limited to, an output data enable signal, a horizontal start signal, and a load signal. In some embodiments, data driver 120 and controller 140 may be implemented in a single integrated circuit and referred to as a timing controller embedded data driver (TED). In other embodiments, data driver 120 and controller 140 may be implemented in separate integrated circuits.

[0049] The scan driver 130 may generate a scan signal SS based on a scan control signal SCTRL received from the controller 140 and may provide the scan signal SS to the plurality of pixels PX via a plurality of scan lines. In some embodiments, the scan driver 130 may sequentially provide the scan signal SS to the plurality of pixels PX on a row-by-row basis. Furthermore, in some embodiments, the scan control signal SCTRL may include, but is not limited to, a scan start signal and a scan clock signal. In some embodiments, the scan driver 130 may be integrated or disposed in a peripheral portion of the display panel 110. In other embodiments, the scan driver 130 may be implemented using one or more integrated circuits.

[0050] The controller 140 (e.g., a timing controller ("TCON")) may receive frame data FDAC and a control signal CTRL from an external host processor (e.g., an application processor ("AP"), a graphics processing unit ("GPU"), or a graphics card). In some embodiments, the frame data FDAC may be RGB image data including red (R) image data, green (G) image data, and blue (B) image data. In addition, in some embodiments, the control signal CTRL may include, but is not limited to, a vertical synchronization signal, a horizontal synchronization signal, an input data enable signal, a main clock signal, and the like. The controller 140 may control the operation of the data driver 120 by providing the frame data FDAC and the data control signal DCTRL to the data driver 120, and may control the operation of the scan driver 130 by providing the scan control signal SCTRL to the scan driver 130.

[0051] In the display device 100 according to an embodiment, the controller 140 may receive frame data FDAC from the host processor at a first frame frequency FF1 in a first mode, and may receive frame data FDAC from the host processor at a second frame frequency FF2 lower than the first frame frequency FF1 in a second mode. In some embodiments, the first frame frequency FF1 may be a normal driving frequency for the display device 100, and may be, but not limited to, approximately 60 Hertz (Hz) or approximately 120 Hz. Furthermore, for example, the second frame frequency FF2 may be, but not limited to, approximately 24 Hz. Since the frame data FDAC is received at the second frame frequency FF2 lower than the first frame frequency FF1 in the second mode, power consumption of the interface between the host processor and the display device 100 may be reduced in the second mode. In some embodiments, the first mode according to the present invention may be, but not limited to, a video mode of a mobile industry processor interface ("MIPI"), and the second mode according to the present invention may be, but not limited to, a command mode of the MIPI.

[0052] In addition, since the frame data FDAC is received at the second frame frequency FF2 lower than the first frame frequency FF1 (e.g., the normal driving frequency) in the second mode, the controller 140 can write the frame data FDAC to the frame memory 160 at the second frame frequency FF2 and can read the frame data FDAC from the frame memory 160 at the first frame frequency FF1. In some embodiments, the controller 140 may include a receiving module 150 for receiving the frame data FDAC, a frame memory 160 for storing the frame data FDAC, and an adaptive refresh panel module 180 for performing a low-frequency driving technique or an adaptive refresh panel ("ARP") technique.

[0053] In the first mode, the receiving module 150 may receive the frame data FDAC at the first frame frequency FF1 and may not write the frame data FDAC into the frame memory 160. In addition, in the first mode, the adaptive refresh panel module 180 may directly receive the frame data FDAC from the receiving module 150 at the first frame frequency FF1. Figure 2 As shown in , in a first mode, for example, in a video mode, when the receiving module 150 receives first frame data FD1, second frame data FD2, third frame data FD3, fourth frame data FD4, fifth frame data FD5, sixth frame data FD6, seventh frame data FD7, eighth frame data FD8, ninth frame data FD9, and tenth frame data FD10 at a first frame frequency FF1 (for example, about 60 Hz), the adaptive refresh panel module 180 can directly receive the first frame data FD1 to the tenth frame data FD10 from the receiving module 150 at the first frame frequency FF1 (for example, about 60 Hz). Here, in the drawings, @ means "at". For example, @150 means "at the receiving module 150".

[0054] In the second mode, the receiving module 150 may receive the frame data FDACT at a second frame frequency FF2 lower than the first frame frequency FF1, and may write the frame data FDACT to the frame memory 160 at the second frame frequency FF2. In addition, in the second mode, the adaptive refresh panel module 180 may read the frame data FDACT from the frame memory 160 at the first frame frequency FF1. Thus, in the second mode, a write operation to the frame memory 160 may be performed at the second frame frequency FF2, and a read operation from the frame memory 160 may be performed at the first frame frequency FF1. For example, Figure 3As shown in FIG, in a second mode, for example, in a command mode, the receiving module 150 may receive first frame data FD1, second frame data FD2, third frame data FD3, and fourth frame data FD4 at a second frame frequency FF2 (for example, approximately 24 Hz), and may write the first frame data FD1 to the fourth frame data FD4 to the frame memory 160 at the second frame frequency FF2 (for example, approximately 24 Hz). When the first frame data FD1 to the fourth frame data FD4 are written to the frame memory 160, the adaptive refresh panel module 180 may read the first frame data FD1 to the fourth frame data FD4 from the frame memory 160 at the first frame frequency FF1 (for example, approximately 60 Hz). Thus, for example, when the first frame frequency FF1 is 60 Hz and the second frame frequency FF2 is 24 Hz, the adaptive refresh panel module 180 may read the first frame data FD1 three times during three frame periods, may read the second frame data FD2 twice during two frame periods, may read the third frame data FD3 three times during three frame periods, and may read the fourth frame data FD4 twice during two frame periods.

[0055] In each frame period in the first mode, the adaptive refresh panel module 180 can perform a still image detection operation to determine whether the frame data FDAT represents a still image, and can selectively perform a driving frequency determination operation to determine the driving frequency DF of the display panel 110 by analyzing the frame data FDAT based on the result of the still image detection operation.

[0056] For example, if it is determined that the frame data FDAC does not represent a still image, or if it is determined that the frame data FDAC represents a moving image, the adaptive refresh panel module 180 may not perform a driving frequency determination operation and may provide the frame data FDAC at a first frame frequency FF1 (e.g., a normal driving frequency) to the data driver 120. Thus, the data driver 120 may drive the display panel 110 at the first frame frequency FF1 (e.g., a normal driving frequency).

[0057] Alternatively, when it is determined that the frame data FDAC represents a still image, the adaptive refresh panel module 180 may perform a drive frequency determination operation and may provide the frame data FDAC at a drive frequency DF determined by the drive frequency determination operation. Thus, the data driver 120 may drive the display panel 110 at the drive frequency DF determined by the drive frequency determination operation. The drive frequency DF may be a low frequency lower than the first frame frequency FF1 (e.g., a normal drive frequency). Therefore, since the display panel 110 is driven at a low frequency (i.e., the drive frequency DF), the power consumption of the display device 100 may be reduced.

[0058] In the second mode, there may be a plurality of consecutive frame periods, in each of which the adaptive refresh panel module 180 reads the same frame data FDAT from the frame memory 160. For example, as explained above, during each of the first frame period FP1, the second frame period FP2, and the third frame period FP3, the adaptive refresh panel module 180 may read the first frame data FD1 three times (see FIG. Figure 5 ). In a first frame period among a plurality of consecutive frame periods, the adaptive refresh panel module 180 may perform a still image detection operation on the frame data FCAT, and may selectively perform a driving frequency determination operation on the frame data FCAT based on a result of the still image detection operation. The adaptive refresh panel module 180 may provide the frame data FCAT to the data driver 120 at the first frame frequency FF1 if it is determined that the frame data FCAT does not represent a still image, and may selectively provide the frame data FCAT to the data driver 120 at the driving frequency DF determined by the driving frequency determination operation if it is determined that the frame data FCAT represents a still image.

[0059] In addition, in the remaining frame periods among the plurality of consecutive frame periods (including the second frame period after the first frame period among the plurality of consecutive frame periods), the adaptive refresh panel module 180 may not perform a still image detection operation on the frame data FCAT, and may perform a driving frequency determination operation on the frame data FCAT. In addition, the adaptive refresh panel module 180 may provide the frame data FCAT to the data driver 120 at the driving frequency DF determined by the driving frequency determination operation. As described above, since the still image detection operation can be performed only in the first frame period among the plurality of consecutive frame periods (in the second mode, the same frame data FCAT is read in the plurality of consecutive frame periods), and may not be performed in at least one subsequent second frame period among the plurality of consecutive frame periods, unnecessary still image detection operations can be omitted, and thus the low-frequency driving technology or the adaptive refresh panel ("ARP") technology can be more efficiently implemented.

[0060] In order to enable the adaptive refresh panel module 180 to perform a still image detection operation in each frame period in the first mode and in the first frame period among a plurality of consecutive frame periods in the second mode, and not to perform the still image detection operation in the remaining frame periods among the plurality of consecutive frame periods in the second mode, the controller 140 may further include a still image detection flag module 170. In some embodiments, the still image detection flag module 170 may generate a still image detection flag signal SIDFS having a first logic level in each frame period in the first mode and in the first frame period among a plurality of consecutive frame periods in the second mode, and may generate a still image detection flag signal SIDFS having a second logic level in the remaining frame periods (including the second frame period) among the plurality of consecutive frame periods in the second mode.

[0061] For example, Figure 4 As shown in, in the video mode (i.e., the first mode), during the first frame period FP1, the second frame period FP2, the third frame period FP3, the fourth frame period FP4, the fifth frame period FP5, the sixth frame period FP6, the seventh frame period FP7, the eighth frame period FP8, the ninth frame period FP9 and the tenth frame period FP10 in which the adaptive refresh panel module 180 receives the first frame data FD1 to the tenth frame data FD10 respectively, the still image detection flag module 170 can generate a still image detection flag signal SIDFS having a first logic level (e.g., a high level H).

[0062] In addition, for example, Figure 5 As shown in, in the command mode (i.e., the second mode), the still image detection flag module 170 can generate a still image detection flag signal SIDFS having a first logic level (i.e., a high level H) in the first frame period FP1 among the first frame period FP1, the second frame period FP2 and the third frame period FP3 (in the first frame period FP1, the second frame period FP2 and the third frame period FP3, the adaptive refresh panel module 180 receives the first frame data FD1), and can generate a still image detection flag signal SIDFS having a second logic level (i.e., a low level L) in the subsequent second frame period FP2 and the third frame period FP3 among the first frame period FP1, the second frame period FP2 and the third frame period FP3. In addition, the still image detection flag module 170 can generate a still image detection flag signal SIDFS having a first logic level (i.e., high level H) in the fourth frame period FP4, the sixth frame period FP6 and the ninth frame period FP9, and can generate a still image detection flag signal SIDFS having a second logic level (i.e., low level L) in the fifth frame period FP5, the seventh frame period FP7, the eighth frame period FP8 and the tenth frame period FP10.

[0063] The adaptive refresh panel module 180 can perform a still image detection operation on the frame data FDAC in response to the still image detection flag signal SIDFS having a first logic level (e.g., a high level H), and can not perform the still image detection operation on the frame data FDAC in response to the still image detection flag signal SIDFS having a second logic level (e.g., a low level L). Thus, the adaptive refresh panel module 180 can perform a still image detection operation in response to the still image detection flag signal SIDFS having a first logic level (e.g., a high level H) in each frame period in the first mode and in the first frame period among a plurality of consecutive frame periods in the second mode, and can not perform the still image detection operation in response to the still image detection flag signal SIDFS having a second logic level (e.g., a low level L) in the remaining frame periods (including the second frame period) among the plurality of consecutive frame periods in the second mode. Therefore, in the second mode, unnecessary still image detection operations can be avoided, and the low-frequency driving technology or the ARP technology can be more efficiently implemented.

[0064] As described above, in the display device 100 according to the embodiment, in the second mode, the frame data FCAT can be written to the frame memory 160, the frame data FCAT can be read from the frame memory 160 in each of the plurality of consecutive frame periods, a still image detection operation for determining whether the frame data FCAT represents a still image can be performed in the first frame period among the plurality of consecutive frame periods, and the still image detection operation can not be performed on the frame data FCAT in the remaining frame periods among the plurality of consecutive frame periods (for example, the subsequent second frame period among the plurality of consecutive frame periods). Therefore, unnecessary still image detection operations can be skipped during the remaining frame periods among the plurality of consecutive frame periods, and the low-frequency driving technology or the ARP technology can be performed more efficiently.

[0065] Figure 6 is a block diagram illustrating an adaptive refresh panel module included in a display device according to an embodiment, Figure 7 is a block diagram illustrating a driving frequency determination module included in a display device according to another embodiment, Figure 8 is a diagram illustrating an example of a flicker lookup table included in a display device according to an embodiment, Figure 9 is a diagram for describing an example of an operation of a segment division module included in a display device according to an embodiment, and Figure 10 is a diagram for describing an example of an operation of a segment frequency decision module included in a display device according to an embodiment.

[0066] refer to Figure 6, the adaptive refresh panel module 180 a included in the display device according to an embodiment may include a still image detection module 210 and a driving frequency decision module 220 .

[0067] The still image detection module 210 may selectively perform a still image detection operation in response to the still image detection flag signal SIDFS, the still image detection operation determining whether the frame data FDAT represents a still image. The still image detection module 210 may receive a signal having a first logic level (e.g., a high level H, see FIG. 1 ) in a first mode (e.g., a video mode). Figure 4 ) of the still image detection flag signal SIDFS; a still image detection flag signal SIDFS having a first logic level (e.g., a high level H, see FIG1 ) may be received in a first frame period among a plurality of consecutive frame periods (in which the frame memory 160 reads the same frame data FDAT) in a second mode (e.g., a command mode); Figure 5 ) of the still image detection flag signal SIDFS; and may receive a second logic level (eg, a low level L, see Figure 5 ) of the still image detection flag signal SIDFS.

[0068] In some embodiments, in response to the still image detection flag signal SIDFS having a first logic level (e.g., a high level H), the still image detection module 210 may perform a still image detection operation on the frame data FDAC by comparing the frame data FDAC in the current frame period with the frame data FDAC in the previous frame period. For example, the still image detection module 210 may compare all pixel image data included in the frame data FDAC in the current frame period with all pixel image data included in the frame data FDAC in the previous frame period. In another example, the still image detection module 210 may compare a representative value (e.g., an average value, a checksum value, etc.) of the frame data FDAC in the current frame period with a representative value of the frame data FDAC in the previous frame period. In addition, when the frame data FDAC in the current frame period is substantially the same as the frame data FDAC in the previous frame period, the still image detection module 210 may generate a still flag signal SFS having a first logic level (e.g., a high level H) (the still flag signal SFS having the first logic level indicates that the frame data FDAC represents a still image), and when the frame data FDAC in the current frame period is different from the frame data FDAC in the previous frame period, the still image detection module 210 may generate a still flag signal SFS having a second logic level (e.g., a low level L) (the still flag signal SFS having the second logic level indicates that the frame data FDAC does not represent a still image). In addition, in response to the still image detection flag signal SIDFS having the second logic level (e.g., a low level L), the still image detection module 210 may not perform a still image detection operation on the frame data FDAC.

[0069] The driving frequency decision module 220 may perform the decision of the display panel 110 (see FIG. 1 ) by analyzing the frame data FDAT in response to the still image detection flag signal SIDFS having the second logic level (e.g., low level L) or the still flag signal SFS having the first logic level (e.g., high level H). Figure 1), and may not perform the driving frequency determination operation on the frame data FDAC in response to the still image detection flag signal SIDFS having a first logic level (e.g., a high level H) and the still flag signal SFS having a second logic level (e.g., a low level L). Thus, when the still image detection flag signal SIDFS has the first logic level and the still flag signal SFS has the second logic level, the driving frequency determination module 220 may provide the frame data FDAC to the data driver 120 without performing the driving frequency determination operation. Furthermore, when the still image detection flag signal SIDFS has the second logic level (e.g., a low level L) or the still flag signal SFS has the first logic level (e.g., a high level H), the driving frequency determination module 220 may provide the frame data FDAC to the data driver 120 according to the driving frequency DF determined by the driving frequency determination operation.

[0070] To perform the driving frequency determination operation, in some embodiments, as Figure 7 As shown in , the driving frequency decision module 220 a may include a flicker lookup table 310 , a segment division module 320 , a segment frequency decision module 330 and a maximum frequency decision module 340 .

[0071] The flicker lookup table 310 may store flicker values ​​corresponding to gray levels (e.g., 256 gray levels from gray level 0 to gray level 255). Here, the flicker value may represent the degree of flicker perceived by the user. For example, Figure 8 As shown in , the flicker lookup table 310 can store a flicker value for four gray levels, but is not limited thereto. In the example, as Figure 8 As shown in FIG, the flicker lookup table 310 can store a flicker value of 0 for gray level 0 to gray level 7, a flicker value of 40 for gray level 8 to gray level 11, a flicker value of 80 for gray level 12 to gray level 15, a flicker value of 120 for gray level 16 to gray level 19, a flicker value of 160 for gray level 20 to gray level 23, a flicker value of 200 for gray level 24 to gray level 27, and a flicker value of 0 for gray level 236 to gray level 255, but the flicker lookup table 310 according to the present invention is not limited to Figure 8 .

[0072] The segment division module 320 may divide the frame data FDAT into a plurality of segment data SDAT1, SDAT2, ..., SDAT9 for a plurality of segments. Figure 9 As shown in FIG, the display panel 110 (see FIG. Figure 1) is divided into a first segment S1, a second segment S2, a third segment S3, a fourth segment S4, a fifth segment S5, a sixth segment S6, a seventh segment S7, an eighth segment S8, and a ninth segment S9, and the frame data FDAT for the display panel 110 may be divided into first segment data SDAT1, second segment data SDAT2, third segment data SDAT3, fourth segment data SDAT4, fifth segment data SDAT5, sixth segment data SDAT6, seventh segment data SDAT7, eighth segment data SDAT8, and ninth segment data SDAT9 for the first segment S1 to the ninth segment S9, respectively. Although Figure 9 An example is shown in which the display panel 110 is divided into nine segments S1 to S9, but the number of the segments S1 to S9 according to the embodiment is not limited to Figure 9 .

[0073] The segment frequency decision module 330 can determine a plurality of segment flicker values ​​corresponding to the grayscale levels of the plurality of segment data SDAT1, SDAT2, ..., SDAT9 by using the flicker lookup table 310, and can determine a plurality of segment frequencies SF1, SF2, ..., SF9 for the plurality of segments according to the plurality of segment flicker values. Figure 8 , the segment frequency decision module 330 may determine a segment flicker value of 0 for each segment data having a gray level from 0 gray level to 7 gray level or from 236 gray level to 255 gray level (e.g., an average gray level or a maximum gray level), and may determine a segment frequency of approximately 1 Hz based on the segment flicker value 0. The segment frequency decision module 330 may determine a segment flicker value of 40 for each segment data having a gray level from 8 gray level to 11 gray level, and may determine a segment frequency of approximately 2 Hz based on the segment flicker value 40. The segment frequency decision module 330 may determine a segment flicker value of 80 for each segment data having a gray level from 12 gray level to 15 gray level, and may determine a segment frequency of approximately 5 Hz based on the segment flicker value 80. The segment frequency decision module 330 may determine a segment flicker value of 120 for each segment data having a gray level from 16 gray level to 19 gray level, and may determine a segment frequency of approximately 10 Hz based on the segment flicker value 120. The segment frequency decision module 330 may determine a segment flicker value 160 for each segment data having gray levels from 20 gray levels to 23 gray levels, and may determine a segment frequency of approximately 30 Hz based on the segment flicker value 160. The segment frequency decision module 330 may determine a segment flicker value 200 for each segment data having gray levels from 24 gray levels to 27 gray levels, and may determine a segment frequency of approximately 60 Hz based on the segment flicker value 200.

[0074] The maximum frequency determination module 340 may receive a plurality of segment frequencies SF1, SF2, ..., SF9 from the segment frequency determination module 330, and may determine the maximum segment frequency of the plurality of segment frequencies SF1, SF2, ..., SF9 as the driving frequency DF of the display panel 110. For example, Figure 10 As shown in FIG, when the first segment frequency SF1, the second segment frequency SF2, the third segment frequency SF3, the fourth segment frequency SF4, the fifth segment frequency SF5, the sixth segment frequency SF6, the seventh segment frequency SF7, the eighth segment frequency SF8, and the ninth segment frequency SF9 of the first segment S1 to the ninth segment S9 are within a range of about 5 Hz to about 10 Hz, the maximum frequency determination module 340 may determine the maximum segment frequency of about 10 Hz among the first segment frequencies SF1 to the ninth segment frequencies SF9 as the driving frequency DF of the display panel 110. When the first frame frequency FF1 (e.g., the normal driving frequency) is about 60 Hz and the driving frequency DF determined by the driving frequency determination module 220 a is about 10 Hz, the driving frequency determination module 220 a may provide the frame data FDAT to the data driver 120 in one frame period among the six frame periods, and thus may drive the display panel 110 at the driving frequency DF of about 10 Hz.

[0075] Figure 11 is a block diagram illustrating an adaptive refresh panel module included in a display device according to an embodiment, and Figure 12 is a diagram for describing an example of an operation of a driving frequency mixing module included in a display device according to an embodiment.

[0076] refer to Figure 11 According to an embodiment, the adaptive refresh panel module 180b included in the display device may include a still image detection module 210, a driving frequency determination module 220, and a driving frequency mixing module 230. In addition to the adaptive refresh panel module 180b further including the driving frequency mixing module 230, Figure 11 The adaptive refresh panel module 180b may have Figure 6 The adaptive refresh panel module 180a has a similar configuration and similar operation.

[0077] The driving frequency mixing module 230 may receive a driving frequency signal DFS from the driving frequency determining module 220, the driving frequency signal DFS representing the driving frequency DF determined by the driving frequency determining operation. Figure 1 ), the driving frequency mixing module 230 may gradually change the driving frequency DF of the display panel 110 from the previous driving frequency to the current driving frequency.

[0078] For example, Figure 12 As shown in FIG, in a case where the previous driving frequency is about 60 Hz and the current driving frequency determined by the driving frequency determining operation is about 7.5 Hz, the driving frequency mixing module 230 may provide eight frame data FDAT to the data driver 120 in the first frame period to the eighth frame period (see FIG. Figure 1 ) to drive the display panel 110 at approximately 60 Hz, four frame data FDAC may be supplied to the data driver 120 in the ninth to sixteenth frame periods to drive the display panel 110 at approximately 30 Hz, two frame data FDAC may be supplied to the data driver 120 in the seventeenth to twenty-fourth frame periods to drive the display panel 110 at approximately 15 Hz, and one frame data FDAC may be supplied to the data driver 120 in the twenty-fifth to thirty-second frame periods to drive the display panel 110 at approximately 7.5 Hz. Therefore, the driving frequency DF of the display panel 110 may be gradually reduced from approximately 60 Hz to approximately 30 Hz, to approximately 15 Hz, and to approximately 7.5 Hz, and thus flickering due to a sudden change in the driving frequency DF may be prevented.

[0079] Figure 13 is a block diagram illustrating a driving frequency decision module included in a display device according to an embodiment, and Figure 14 is a diagram showing an example of a still image detection signal in the display device according to the embodiment.

[0080] refer to Figure 13 The driving frequency decision module 220b included in the display device according to the embodiment may include a flicker lookup table 310, a segment division module 320, a segment frequency decision module 330, a maximum frequency decision module 340, and a final frequency decision module 350. In addition to the final frequency decision module 350, the driving frequency decision module 220b may also include the final frequency decision module 350. Figure 13 The driving frequency determination module 220b may have Figure 7 The driving frequency determination module 220a has a similar configuration and similar operation.

[0081] Including the driving frequency determination module 220b Figure 1 The adaptive refresh panel module 180 can be Figure 1The still image detection flag module 170 receives not only the still image detection flag signal SIDFS, but also the frame repetition number information FRNI. The frame repetition number information FRNI may represent the number of multiple consecutive frame periods in which the same frame data FDAT is read from the frame memory 160 in the second mode (e.g., command mode). In some embodiments, in order to provide the frame repetition number information FRNI to the adaptive refresh panel module 180, the still image detection flag module 170 may provide the still image detection flag signal SIDFS including multiple pulses to the adaptive refresh panel module 180, and the number of pulses of the still image detection flag signal SIDFS may correspond to the number of multiple consecutive frame periods. For example, as Figure 14 As shown in FIG, the still image detection flag module 170 may be provided in the first frame period FP1 (in the first frame period FP1 from Figure 1 The still image detection flag signal SIDFS with three pulses in the first frame data FD1 to be read three times of the frame memory 160 is provided as the frame repetition number information FRNI, the still image detection flag signal SIDFS with two pulses in the fourth frame period FP4 (the second frame data FD2 to be read twice is provided in the fourth frame period FP4) is provided as the frame repetition number information FRNI, the still image detection flag signal SIDFS with three pulses in the sixth frame period FP6 (the third frame data FD3 to be read three times is provided in the sixth frame period FP6) is provided as the frame repetition number information FRNI, and the still image detection flag signal SIDFS with two pulses in the ninth frame period FP9 (the fourth frame data FD4 to be read twice is provided in the ninth frame period FP9) is provided as the frame repetition number information FRNI.

[0082] The final frequency determination module 350 can be obtained from Figure 1The still image detection flag module 170 receives the frame repetition number information FRNI, may receive the maximum segment frequency MSF among the multiple segment frequencies SF1, SF2, ..., SF9 from the maximum frequency determination module 340, and may determine the driving frequency DF of the display panel 110 based on the frame repetition number information FRNI and the maximum segment frequency MSF. In some embodiments, the final frequency determination module 350 may determine the frame change frequency by dividing the first driving frequency or the normal driving frequency by the number of consecutive frame periods represented by the frame repetition number information FRNI, and may determine the higher of the maximum segment frequency MSF and the frame change frequency as the driving frequency DF of the display panel 110. For example, if the normal driving frequency is approximately 60 Hz, the frame repetition number information FRNI represents three, and the maximum segment frequency MSF is approximately 10 Hz, the final frequency determination module 350 may determine the frame change frequency to be approximately 20 Hz by dividing approximately 60 Hz by three, and may determine the driving frequency DF to be approximately 20 Hz. In another example, when the normal driving frequency DF is approximately 60 Hz, the frame repetition number information FRNI represents three and the maximum segment frequency MSF is approximately 30 Hz, the final frequency decision module 350 may decide the frame change frequency to be approximately 20 Hz by dividing approximately 60 Hz by three, and since the maximum segment frequency MSF is greater than the frame change frequency, the driving frequency DF may be decided to be approximately 30 Hz.

[0083] Figure 15 is a flowchart illustrating a method of operating a display device according to an embodiment.

[0084] refer to Figure 1 and Figure 15In a first mode (e.g., video mode) (S410: Video Mode), the receiving module 150 may receive frame data FDAT at a first frame frequency FF1 (e.g., approximately 60 Hz) (S420). The adaptive refresh panel module 180 may directly receive the frame data FDAT from the receiving module 150 at the first frame frequency FF1. The adaptive refresh panel module 180 may perform a still image detection operation to determine whether the frame data FDAT represents a still image (S422), and may selectively perform a driving frequency determination operation to determine the driving frequency DF of the display panel 110 by analyzing the frame data FDAT based on the result of the still image detection operation (S424). If the frame data FDAT does not represent a still image, the adaptive refresh panel module 180 may not perform the driving frequency determination operation and may provide the frame data FDAT to the data driver 120 at the first frame frequency FF1. In addition, the data driver 120 may drive the display panel 110 at the first frame frequency FF1 (S430). In addition, in the case where the frame data FDAT represents a still image, the adaptive refresh panel module 180 may perform a driving frequency determination operation and selectively provide the frame data FDAT to the data driver 120 at a driving frequency DF determined by the driving frequency determination operation. In addition, the data driver 120 may selectively drive the display panel 110 at the driving frequency DF determined by the driving frequency determination operation (S430).

[0085] In the second mode (e.g., command mode) (S410: Command Mode), the receiving module 150 may receive the frame data FDAT at a second frame frequency FF2 (e.g., approximately 24 Hz) lower than the first frame frequency FF1 (S440), and may write the frame data FDAT to the frame memory 160 at the second frame frequency FF2 (S445). The adaptive refresh panel module 180 may read the frame data FDAT from the frame memory 160 at the first frame frequency FF1 (S450).

[0086] In the first frame period among a plurality of consecutive frame periods in which the same frame data FDAT is read from the frame memory 160 (S455: Yes), the adaptive refresh panel module 180 may perform a still image detection operation on the frame data FDAT (S460), and may selectively perform a driving frequency determination operation (S462) based on the result of the still image detection operation. In the first frame period, if the frame data FDAT does not represent a still image, the adaptive refresh panel module 180 may not perform the driving frequency determination operation and may provide the frame data FDAT to the data driver 120 to drive the display panel 110 (S464). In addition, if the frame data FDAT represents a still image, the adaptive refresh panel module 180 may perform the driving frequency determination operation and may selectively provide the frame data FDAT to the data driver 120 to selectively drive the display panel 110 (S464).

[0087] If the receiving module 150 does not receive new frame data FDAT (S480: No), in a subsequent second frame period among the plurality of consecutive frame periods (S455: No), the adaptive refresh panel module 180 may read the frame data FDAT from the frame memory 160 (S450) and may perform a driving frequency determination operation on the frame data FDAT without performing a still image detection operation (S472) on the frame data FDAT. In the second frame period, the adaptive refresh panel module 180 may selectively provide the frame data FDAT to the data driver 120 to selectively drive the display panel 110 according to the driving frequency DF determined by the driving frequency determination operation (S474). If new frame data FDAT is received (S480: Yes), the receiving module 150 may receive and write the new frame data FDAT (S440 and S445).

[0088] As described above, in the method of operating the display device 100 according to the embodiment, the frame data FCAT can be written to the frame memory 160, the frame data FCAT can be read from the frame memory 160 in each of a plurality of consecutive frame periods, a still image detection operation for determining whether the frame data FCAT represents a still image can be performed in the first frame period among the plurality of consecutive frame periods, and the still image detection operation can be not performed on the frame data FCAT in the remaining frame periods among the plurality of consecutive frame periods (for example, the subsequent second frame period among the plurality of consecutive frame periods). Therefore, unnecessary still image detection operations can be avoided, and the low-frequency driving technology or the ARP technology can be more efficiently implemented.

[0089] Figure 16 An electronic device including a display device according to an embodiment.

[0090] refer to Figure 16, the electronic device 1100 may include a processor 1110, a memory device 1120, a storage device 1130, an input / output ("I / O") device 1140, a power supply 1150, and a display device 1160. The electronic device 1100 may also include a plurality of ports for communicating with a video card, a sound card, a memory card, a universal serial bus ("USB") device, other electronic devices, and the like.

[0091] The processor 1110 may perform various computing functions or tasks. The processor 1110 may be an application processor (AP), a microprocessor, a central processing unit ("CPU"), or the like. The processor 1110 may be coupled to other components via an address bus, a control bus, a data bus, or the like. In addition, in some embodiments, the processor 1110 may also be coupled to an expansion bus such as a peripheral component interconnect ("PCI") bus.

[0092] The memory device 1120 may store data used for the operation of the electronic device 1100. For example, the memory device 1120 may include at least one non-volatile memory device, such as an erasable programmable read-only memory ("EPROM") device, an electrically erasable programmable read-only memory ("EEPROM") device, a flash memory device, a phase-change random access memory ("PRAM") device, a resistive random access memory ("RRAM") device, a nano-floating gate memory ("NFGM") device, a polymer random access memory ("PoRAM") device, a magnetic random access memory ("MRAM") device, a ferroelectric random access memory ("FRAM") device, etc., and / or at least one volatile memory device, such as a dynamic random access memory ("DRAM") device, a static random access memory ("SRAM") device, a mobile dynamic random access memory (mobile DRAM) device, etc.

[0093] The storage device 1130 may be a solid-state drive ("SSD") device, a hard disk drive ("HDD") device, a CD-ROM device, etc. The I / O device 1140 may be an input device such as a keyboard, a keypad, a mouse, a touch screen, etc., and an output device such as a printer, a speaker, etc. The power supply 1150 may provide power for the operation of the electronic device 1100. The display device 1160 may be coupled to other components via a bus or other communication link.

[0094] In the display device 1160, the frame data FDAT (see Figure 1 ) is written into the frame memory 160 (see Figure 1), the same frame data FDAC can be read from the frame memory 160 in each of a plurality of consecutive frame periods, a still image detection operation for determining whether the frame data FDAC represents a still image can be performed in the first frame period among the plurality of consecutive frame periods, and the still image detection operation for the frame data FDAC can be omitted in the remaining frame periods among the plurality of consecutive frame periods (including the subsequent second frame period among the plurality of consecutive frame periods). Therefore, unnecessary still image detection operations can be skipped, and the low-frequency driving technology or the ARP technology can be performed more efficiently.

[0095] The present inventive concept can be applied to any display device 1160 and any electronic device 1100 including the display device 1160. For example, the present inventive concept can be applied to mobile phones, smart phones, wearable electronic devices, tablet computers, televisions ("TVs"), digital TVs, 3D TVs, personal computers ("PCs"), home appliances, laptop computers, personal digital assistants ("PDAs"), portable multimedia players ("PMPs"), digital cameras, music players, portable game consoles, navigation devices, and the like.

[0096] The foregoing is illustrative of embodiments and is not to be construed as limiting the embodiments. Although a few embodiments have been described, those skilled in the art will readily appreciate that many modifications in the embodiments are possible without materially departing from the novel teachings and advantages of the present inventive concept. Therefore, all such modifications are intended to be included within the scope of the present inventive concept as defined in the claims. Therefore, it will be understood that the foregoing is illustrative of various embodiments and is not to be construed as limited to the specific embodiments disclosed, and that modifications of the disclosed embodiments as well as other embodiments are intended to be included within the scope of the appended claims.

Claims

1. A display device, wherein: The display device includes: A display panel, wherein the display panel comprises a plurality of pixels; a data driver that provides data signals to the plurality of pixels; and A controller that controls the data driver, writes frame data into a frame memory, reads the frame data in each of a plurality of frame periods, performs a still image detection operation to determine whether the frame data represents a still image in a first frame period among the plurality of frame periods, and does not perform the still image detection operation in a second frame period after the first frame period among the plurality of frame periods.

2. The display device according to claim 1, wherein In the first frame period, the controller selectively performs a driving frequency determination operation of determining a driving frequency for the display panel by analyzing the frame data according to a result of the still image detection operation, and Here, in the second frame period, the controller performs the driving frequency determination operation instead of performing the still image detection operation.

3. The display device according to claim 1, wherein The controller includes: A receiving module, wherein the receiving module receives the frame data; the frame memory storing the frame data; and Adaptive refresh panel module, wherein in each frame period in the first mode and in the first frame period in the second mode, the adaptive refresh panel module performs the still image detection operation on the frame data, and selectively performs a driving frequency determination operation for determining a driving frequency for the display panel by analyzing the frame data according to a result of the still image detection operation, and In the second frame period in the second mode, the adaptive refresh panel module does not perform the still image detection operation on the frame data, and performs the driving frequency determination operation on the frame data.

4. The display device according to claim 3, wherein: In the first mode, the receiving module receives the frame data at a first frame frequency and does not write the frame data into the frame memory. Wherein, in the first mode, the adaptive refresh panel module directly receives the frame data from the receiving module at the first frame frequency, Wherein, in the second mode, the receiving module receives the frame data at a second frame frequency lower than the first frame frequency, and writes the frame data into the frame memory at the second frame frequency, and Wherein, in the second mode, the adaptive refresh panel module reads the frame data from the frame memory at the first frame frequency.

5. The display device according to claim 4, wherein The first mode is a video mode, and the second mode is a command mode. The display device according to claim 3 , wherein: The controller further includes: A still image detection flag module, which generates a still image detection flag signal with a first logic level in each frame period in the first mode and in the first frame period in the second mode, and generates the still image detection flag signal with a second logic level in the second frame period in the second mode.

7. The display device according to claim 6, wherein: The adaptive refresh panel module performs the still image detection operation on the frame data in response to the still image detection flag signal having the first logic level, and does not perform the still image detection operation on the frame data in response to the still image detection flag signal having the second logic level.

8. The display device according to claim 6, wherein: The adaptive refresh panel module includes: a still image detection module that, in response to the still image detection flag signal having the first logic level, performs the still image detection operation of determining whether the frame data represents the still image by comparing the frame data in a current frame period with the frame data in a previous frame period, and generates a still flag signal having the first logic level when the frame data represents the still image; and A driving frequency determination module that performs the driving frequency determination operation of determining the driving frequency for the display panel by analyzing the frame data in response to the still image detection flag signal having the second logic level or the still flag signal having the first logic level.

9. The display device according to claim 8, wherein The driving frequency decision module does not perform the driving frequency decision operation in response to the still image detection flag signal having the first logic level and the still flag signal having the second logic level.

10. The display device according to claim 8, wherein When the frame data in the current frame period is the same as the frame data in the previous frame period, the still image detection module generates the still flag signal having the first logic level, and when the frame data in the current frame period is different from the frame data in the previous frame period, the still image detection module generates the still flag signal having the second logic level.

11. The display device according to claim 8, wherein When the still image detection flag signal has the first logic level and the still flag signal has the second logic level, the driving frequency decision module provides the frame data to the data driver without performing the driving frequency decision operation, and When the still image detection flag signal has the second logic level or the still flag signal has the first logic level, the driving frequency determination module selectively provides the frame data to the data driver according to the driving frequency determined by the driving frequency determination operation.

12. The display device according to claim 8, wherein The driving frequency determination module includes: a flicker lookup table storing flicker values ​​corresponding to grayscale levels; a segment division module, the segment division module dividing the frame data into a plurality of segment data respectively used for a plurality of segments; a segment frequency decision module that determines a plurality of segment flicker values ​​corresponding to grayscale levels of the plurality of segment data by using the flicker lookup table, and determines a plurality of segment frequencies respectively for the plurality of segments based on the plurality of segment flicker values; and A maximum frequency determination module is configured to determine a maximum segment frequency of the plurality of segment frequencies as the driving frequency for the display panel.

13. The display device according to claim 8, wherein The still image detection flag module provides frame repetition number information to the adaptive refresh panel module, where the frame repetition number information represents the number of the plurality of frame periods for reading the same frame data from the frame memory in the second mode.

14. The display device according to claim 13, wherein: When providing the frame repetition number information to the adaptive refresh panel module, the still image detection flag module provides the still image detection flag signal to the adaptive refresh panel module, the still image detection flag signal including pulses corresponding to the number of the plurality of frame periods.

15. The display device according to claim 13, wherein The driving frequency determination module includes: a flicker lookup table storing flicker values ​​corresponding to grayscale levels; a segment division module, the segment division module dividing the frame data into a plurality of segment data respectively used for a plurality of segments; a segment frequency determination module that determines a plurality of segment flicker values ​​corresponding to grayscale levels of the plurality of segment data by using the flicker lookup table, and determines a plurality of segment frequencies respectively for the plurality of segments based on the plurality of segment flicker values; a maximum frequency determination module, the maximum frequency determination module determining a maximum segment frequency among the plurality of segment frequencies; and A final frequency determination module is configured to determine the driving frequency for the display panel based on the frame repetition number information and the maximum segment frequency.

16. The display device according to claim 15, wherein The final frequency decision module determines a frame change frequency by dividing a normal driving frequency by the number of the plurality of frame periods represented by the frame repetition number information, and decides a higher frequency between the maximum segment frequency and the frame change frequency as the driving frequency for the display panel.

17. The display device according to claim 8, wherein: The adaptive refresh panel module also includes: A driving frequency mixing module is configured to gradually change the driving frequency for the display panel from the previous driving frequency to the current driving frequency when the current driving frequency determined by the driving frequency determining operation is different from the previous driving frequency for the display panel.

18. A display device, wherein: The display device includes: A display panel, wherein the display panel comprises a plurality of pixels; a data driver that provides data signals to the plurality of pixels; and A controller for controlling the data driver, wherein the controller comprises: Frame memory; a receiving module that receives frame data at a first frame frequency in a first mode, receives the frame data at a second frame frequency lower than the first frame frequency in a second mode, and writes the frame data to the frame memory at the second frame frequency in the second mode; and An adaptive refresh panel module receives the frame data from the receiving module at the first frame frequency in the first mode, reads the frame data from the frame memory at the first frame frequency in the second mode, performs a still image detection operation to determine whether the frame data represents a still image in each frame period in the first mode and in the first frame period among multiple frame periods in the second mode, and does not perform the still image detection operation on the frame data in a second frame period after the first frame period among the multiple frame periods in the second mode.

19. The display device according to claim 18, wherein: The adaptive refresh panel module selectively performs a driving frequency determination operation of determining a driving frequency for the display panel by analyzing the frame data according to a result of the still image detection operation in each frame period in the first mode and in the first frame period in the second mode, and Wherein, in the second frame period in the second mode, the adaptive refresh panel module performs the driving frequency determination operation but does not perform the still image detection operation.

20. A method of operating a display device, wherein: The method comprises: In a first mode, frame data is received at a first frame frequency; In the first mode, performing a still image detection operation of determining whether the frame data represents a still image; In the first mode, a driving frequency determination operation of determining a driving frequency for a display panel by analyzing the frame data is selectively performed according to a result of the still image detection operation; In a second mode, receiving the frame data at a second frame frequency lower than the first frame frequency; In the second mode, writing the frame data into a frame memory at the second frame frequency; in the second mode, reading the frame data from the frame memory at the first frame frequency; performing the still image detection operation on the frame data read from the frame memory in a first frame period among a plurality of frame periods in the second mode; selectively performing the driving frequency decision operation in the first frame period in the second mode according to a result of the still image detection operation; and In a second frame period following the first frame period among the plurality of frame periods in the second mode, the driving frequency decision operation is performed without performing the still image detection operation.

Images