This application claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2021-0157564, filed on Nov. 16, 2021 in the Korean Intellectual Property Office (KIPO), the disclosure of which is incorporated by reference herein in its entirety.
Embodiments of the present inventive concept relate to display devices, and more particularly to display devices controlling currents, and methods of operating the display devices.
A display device may include a display panel and a display panel driver to produce an image based on image data. The display device may employ a current control technique to prevent an overcurrent in the display device. The current control technique may determine a current control value by analyzing current frame data, and may apply the current control value when the display device displays an image based on next frame data. Thus, a frame delay may exist between determining the current control value and applying the current control value. Accordingly, when a low gray image (eg., a black image) is displayed in a previous frame period, and a high gray image (e.g., a white image) is displayed in a current frame period, a current control value corresponding to the low gray image may be applied in the current frame period, rather than a current control value corresponding to the high gray image, and thus, the overcurrent may occur
Some embodiments of the present inventive concept provide a display device capable of controlling a current on a line-by-line basis.
Some embodiments of the present inventive concept provide a method of operating a display device capable of controlling a current on a line-by-line basis.
According to embodiments of the present inventive concept, there is provided a display device including: a display panel including first through N-th pixel rows, where N is an integer greater than 1; and a panel driver configured to sequentially receive first through N-th line data for the first through the N-th pixel rows in each frame period, and to drive the display panel based on the first through the N-th line data, the panel driver including: a current control circuit configured to determine a current control value for a (K+1)-th pixel row based on the first through K-th line data for the first through K-th pixel rows received in a current frame period and (K+1)-th through the N-th line data for the (K+1)-th through the N-th pixel rows received in a previous frame period, where K is an integer greater than 0 and less than or equal to N; and a data correction circuit configured to correct the (K+1)-th line data for the (K+1)-th pixel row based on the current control value in the current frame period.
The current control circuit is configured to: determine an average panel luminance level based on the first through the K-th line data received in the current frame period and the (K+1)-th through the N-th line data received in the previous frame period; and determine the current control value based on the average panel luminance level.
The current control circuit decreases the current control value as the average panel luminance level increases
The current control circuit includes: a gray-luminance converter configured to convert gray levels represented by pixel data included in the first through N-th line data for the first through the N-th pixel rows into pixel luminances for each of the first through the N-th pixel rows; a line luminance calculator configured to calculate a line luminance for each of the first through the N-th pixel rows by summing the pixel luminances for each of the first through the N-th pixel rows; an average luminance level determiner configured to store line luminances for the first through the N-th pixel rows in a first-in first-out (FIFO) manner, and to determine an average panel luminance level based on the line luminances for the first through the N-th pixel rows; a luminance domain scale factor determiner configured to determine a luminance domain scale factor corresponding to the average panel luminance level; and a gray domain scale factor determiner configured to convert the luminance domain scale factor into a gray domain scale factor as the current control value.
The gray-luminance converter converts a gray level represented by each pixel data into a pixel luminance by using an equation 350 “PXLUM = (Gray)^Gamma”, where PXLUM represents the pixel luminance, Gray represents the gray level, and Gamma represents a gamma value of the display device.
The gray-luminance converter includes a gray-luminance lookup table that stores a plurality of pixel luminances corresponding to a plurality of gray levels, and wherein the gray-luminance converter converts a gray level represented by each pixel data into a pixel luminance by using the gray-luminance lookup table.
The average luminance level determiner includes: a FIFO memory configured to store the line luminances for the first through the N-th pixel rows, the FIFO memory configured to remove a previous line luminance for a current pixel row stored in the previous frame period while storing a current line luminance for the current pixel row in the current frame period; and an average luminance level calculator configured to calculate a panel luminance by summing the line luminances stored in the FIFO memory, and to determine the average panel luminance level by dividing the panel luminance by a maximum panel luminance.
The luminance domain scale factor determiner is configured to: determine the luminance domain scale factor as a maximum luminance domain scale factor when the average panel luminance level is less than a reference luminance level; and decrease the luminance domain scale factor as the average panel luminance level increases when the average panel luminance level is greater than or equal to the reference luminance level.
The gray domain scale factor determiner converts the luminance domain scale factor into the gray domain scale factor by using an equation 550 “GDSF = (LDSF)^(1/Gamma)”, where GDSF represents the gray domain scale factor, LDSF represents the luminance domain scale factor, and Gamma represents a gamma value of the display device.
The gray domain scale factor determiner includes a luminance-gray scale factor lookup table that stores a plurality of gray domain scale factors corresponding to a plurality of luminance domain scale factors, and wherein the gray domain scale factor determiner converts the luminance domain scale factor into the gray domain scale factor by using the luminance-gray scale factor lookup table.
The data correction circuit is configured to: receive a gray domain scale factor as the current control value; and multiply pixel data included in the (K+1)-th line data by the gray domain scale factor to correct the (K+1)-th line data.
The current control circuit is configured to: calculate a scaled panel luminance based on line luminances for the first through the N-th pixel rows and luminance domain scale factors for the first through the N-th pixel rows; compare the scaled panel luminance with a panel luminance limit value; and decrease the current control value when the scaled panel luminance exceeds the panel luminance limit value.
In a case where the scaled panel luminance exceeds the panel luminance limit value when the K-th line data are received, the current control circuit determines the current control values for the (K+1)-th through the N-th pixel rows in the current frame period as a minimum current control value.
In a case where the scaled panel luminance exceeds the panel luminance limit value when the K-th line data are received, the current control circuit decreases the current control values for the (K+1)-th through the N-th pixel rows in the current frame period to a target current control value.
The current control circuit includes: a gray-luminance converter configured to convert gray levels represented by pixel data included in the first through N-th line data for the first through the N-th pixel rows into pixel luminances for each of the first through the N-th pixel rows; a line luminance calculator configured to calculate a line luminance for each of the first through the N-th pixel rows by summing the pixel luminances for each of the first through the N-th pixel rows; an average luminance level determiner configured to store line luminances for the first through the N-th pixel rows in a first-in first-out (FIFO) manner, and to determine an average panel luminance level based on the line luminances for the first through the N-th pixel rows; a luminance domain scale factor determiner configured to determine a luminance domain scale factor corresponding to the average panel luminance level; a scaled panel luminance calculator configured to multiply the line luminances for the first through the N-th pixel rows by luminance domain scale factors for the first through the N-th pixel rows, respectively, and to calculate a scaled panel luminance by summing results of the multiplication; an overcurrent protector configured to compare the scaled panel luminance with a panel luminance limit value, and to decrease the luminance domain scale factor output from the luminance domain scale factor determiner when the scaled panel luminance exceeds the panel luminance limit value; and a gray domain scale factor determiner configured to convert the luminance domain scale factor output from the overcurrent protector into a gray domain scale factor as the current control value.
According to embodiments of the present inventive concept, there is provided a display device including: a display panel including first through N-th pixel rows, where N is an integer greater than 1; and a panel driver configured to sequentially receive first through N-th line data for the first through the N-th pixel rows in each frame period, and to drive the display panel based on the first through the N-th line data, the panel driver including: a current control circuit configured to determine an average panel luminance level based on the first through K-th line data for the first through K-th pixel rows received in a current frame period and (K+1)-th through the N-th line data for (K+1)-th through the N-th pixel rows received in a previous frame period, and to determine a scale factor for the (K+1)-th pixel row based on the average panel luminance level, where K is an integer greater than 0 and less than or equal to N; and a data correction circuit configured to correct the (K+1)-th line data for the (K+1)-th pixel row based on the scale factor in the current frame period.
The current control circuit decreases the scale factor as the average panel luminance level increases.
The data correction circuit multiplies pixel data included in the (K+1)-th line data by the scale factor to correct the (K+1)-th line data.
According to embodiments of the present inventive concept, there is provided a method of operating a display device, the method including: receiving K-th line data for a K-th pixel row among first through N-th pixel rows in a current frame period, where N is an integer greater than 1, and K is an integer greater than 0 and less than or equal to N; determining a current control value for a (K+1)-th pixel row based on first through the K-th line data for the first through the K-th pixel rows received in the current frame period and (K+1)-th through N-th line data for the (K+1)-th through the N-th pixel rows received in a previous frame period; receiving the (K+1)-th line data for the (K+1)-th pixel row among the first through the N-th pixel rows in the current frame period; correcting the (K+1)-th line data based on the current control value in the current frame period; and driving the (K+1)-th pixel row based on the corrected (K+1)-th line data.
The method further including: calculating a scaled panel luminance based on line luminances for the first through the N-th pixel rows and luminance domain scale factors for the first through the N-th pixel rows; comparing the scaled panel luminance with a panel luminance limit value; and decreasing the current control value when the scaled panel luminance exceeds the panel luminance limit value
According to embodiments of the present inventive concept, there is provided a display device including: a display panel including a plurality of pixel rows arranged in sequence; and a panel driver configured to sequentially receive a plurality of line data for the pixel rows in each frame period, and to drive the display panel based on the line data, the panel driver including: a current control circuit configured to determine a current control value for a specific pixel row based on line data received for the pixel rows arranged before the specific pixel row in a current frame period, line data received for the specific pixel row in a previous frame period and line data received for pixel rows arranged after the specific pixel row in the previous frame period; and a data correction circuit configured to correct the line data for the specific pixel row based on the current control value in the current frame period.
As described above, in a display device and a method of operating the display device according to embodiments of the present inventive concept, when K-th line data for a K-th pixel row are received, a current control value for a (K+1)-th pixel row may be determined based on first through K-th line data received in a current frame period and (K+1)-th through N-th line data received in a previous frame period, and (K+ 1)-th line data may be corrected based on the current control value. Accordingly, an overcurrent caused by a delay between determining the current control value and applying the current control value may be prevented.
Illustrative, non-limiting embodiments of the present inventive concept will be more clearly understood from the following detailed description in conjunction with the accompanying drawings.
Hereinafter, embodiments of the present inventive concept will be explained in detail with reference to the accompanying drawings.
Referring to
The display panel 110 may include first through N-th pixel rows PXR1, PXR2, ..., PXRN each including the plurality of pixels PX, where N is an integer greater than 1. Here, each pixel row PXR1, PXR2, ..., PXRN may be the same row of the pixels PX, and may be one line or one row of the pixels PX receiving the same scan signal SS. In some embodiments of the present inventive concept, each pixel PX may include at least two transistors, at least one capacitor and a light emitting element, and the display panel 110 may be a light emitting display panel. For example, the light emitting element may be an organic light emitting diode (OLED), and the display panel 110 may be an OLED display panel. In other examples, the light emitting element may be a light emitting diode (LED), a quantum dot (QD) light emitting diode, a micro light emitting diode, an inorganic light emitting diode, or any other light emitting element. In other embodiments of the present inventive concept, each pixel PX may include a switching transistor, and a liquid crystal capacitor coupled to the switching transistor, and the display panel 110 may be a liquid crystal display (LCD) panel. However, the display panel 110 is not limited to the light emitting display panel and the LCD panel, and may be any other display panel.
The scan driver 130 may generate the scan signals SS based on a scan control signal SCTRL received from the controller 150, may sequentially provide the scan signals SS to the plurality of pixels PX on a pixel row basis. In some embodiments of the present inventive concept, the scan control signal SCTRL may include, but is not limited to, a scan start signal and a scan clock signal. In some embodiments of the present inventive concept, the scan driver 130 may be integrated or formed in a peripheral region of the display panel 110. In other embodiments of the present inventive concept, the scan driver 130 may be implemented with one or more integrated circuits.
The data driver 140 may generate the data signals DS based on output image data ODAT and a data control signal DCTRL received from the controller 150, and may provide the data signals DS to the plurality of pixels PX. In some embodiments of the present inventive concept, the data control signal DCTRL may include, but is not limited to, a horizontal start signal and a load signal. In some embodiments of the present inventive concept, the data driver 140 and the controller 150 may be implemented with a single integrated circuit, and the single integrated circuit may be referred to as a timing controller embedded data driver (TED). In other embodiments of the present inventive concept, the data driver 140 and the controller 150 may be implemented with separate integrated circuits.
The controller 150 (e.g., a timing controller (TCON)) may receive input image data IDAT and a control signal CTRL from an external host processor (e.g., an application processor (AP), a graphics processing unit (GPU), a graphics card, etc.). The input image data IDAT may include first through N-th line data LD1, LD2, ..., LDN for the first through the N-th pixel rows PXR1, PXR2, ..., PXRN, and the controller 150 may sequentially receive the first through the N-th line data LD1 through LDN in each frame period. In some embodiments of the present inventive concept, 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 master clock signal, etc. The controller 150 may generate the output image data ODAT, the data control signal DCTRL, and the scan control signal SCTRL based on the input image data IDAT and the control signal CTRL. The controller 150 may control an operation of the data driver 140 by providing the output image data ODAT and the data control signal DCTRL to the data driver 140, and may control an operation of the scan driver 130 by providing the scan control signal SCTRL to the scan driver 130.
In the display device 100, the panel driver 120 may sequentially receive the first through the N-th line data LD1 through LDN for the first through the N-th pixel rows PXR1 through PXRN in each frame period, and may perform a current control operation on a line-by-line basis or a pixel row-by-pixel row basis. In some embodiments of the present inventive concept, the panel driver 120 may generate a current control value CCV for next line data when current line data are received, and may correct the next line data based on the current control value CCV. To perform this operation, the controller 150 of the panel driver 120 may include a current control block 160 and a data correction block 170. The current control block 160 and the data correction block 170 may each be implemented in a circuit.
The current control block 160 may generate the current control value CCV for the next line data when the current line data are received. For example, as illustrated in
In some embodiments of the present inventive concept, as described below with reference to
The data correction block 170 may correct the (K+1)-th line data LDK+1 for the (K+1)-th pixel row based on the current control value CCV in the current frame period CFP. In some embodiments of the present inventive concept, the data correction block 170 may receive a gray domain scale factor as the current control value CCV from the current control block 160, and may multiply pixel data included in the (K+1)-th line data LDK+1 by the gray domain scale factor to correct the (K+1)-th line data LDK+1. For example, the current control value CCV, or the gray domain scale factor may be greater than or equal to 0 and less than or equal to 1, and the corrected (K+1)-th line data LDK+1 may be decreased compared with the original (K+1)-th line data LDK+1. Thus, a current of the (K+1)-th pixel row driven based on the corrected (K+1)-th line data LDK+1 may be decreased compared with a current of the (K+1)-th pixel row driven based on the original (K+1)-th line data LDK+1.
In a conventional display device, a current control operation is performed with a period (or cycle) of one frame on a frame-by-frame basis. For example, as illustrated in
According to an embodiment of the present inventive concept, there is provided a display device 100 including: a display panel 110 including first through N-th pixel rows (PXR1-PXRN), where N is an integer greater than 1; and a panel driver 120 configured to sequentially receive first through N-th line data (LD1-LDN) for the first through the N-th pixel rows (PXR1-PXRN) in each frame period, and to drive the display panel 110 based on the first through the N-th line data (LD1-LDN), the panel driver 120 including: a current control block (or circuit) 160 configured to determine a current control value CCV for a (K+1)-th pixel row based on the first through K-th line data for the first through K-th pixel rows received in a current frame period CFP and (K+1)-th through the N-th line data for the (K+1)-th through the N-th pixel rows received in a previous frame period PFP, where K is an integer greater than 0 and less than or equal to N; and a data correction block (or circuit) 170 configured to correct the (K+1)-th line data for the (K+1)-th pixel row based on the current control value CCV in the current frame period CFP.
Referring to
The gray-luminance converter 210 may convert gray levels represented by pixel data PXD included in line data LD for each pixel row into pixel luminances PXLUM for each pixel row.
In other embodiments of the present inventive concept, as illustrated in
The line luminance calculator 220 may calculate a line luminance LLUM for each pixel row by summing the pixel luminances PXLUM for each pixel row. Since first through N-th line data for first through N-th pixel rows are sequentially received, the line luminance calculator 220 may sequentially calculate first through N-th line luminances LLUM for the first through the N-th line data, and may sequentially output the first through the N-th line luminances LLUM.
The average luminance level determiner 230 may store the line luminances LLUM for the first through the N-th pixel rows in a first-in first-out (FIFO) manner. For example, the average luminance level determiner 230 may sequentially receive and store the N line luminances LLUM for the first through the N-th pixel rows, and may maintain the N line luminances LLUM by removing the oldest line luminance LLUM while storing newest line luminance LLUM. Further, the average luminance level determiner 230 may determine an average panel luminance level APL based on the N line luminances LLUM for the first through the N-th pixel rows. In some embodiments of the present inventive concept, the average panel luminance level APL may be referred to as an average picture level.
In some embodiments of the present inventive concept, as illustrated in
The luminance domain scale factor determiner 240 may determine a luminance domain scale factor LDSF corresponding to the average panel luminance level APL. For example, the luminance domain scale factor determiner 240 may decrease the luminance domain scale factor LDSF as the average panel luminance level APL increases. In the alternative, the luminance domain scale factor determiner 240 may increase the luminance domain scale factor LDSF as the average panel luminance level APL decreases Further, the luminance domain scale factor LDSF determined by the luminance domain scale factor determiner 240 may have, but is not limited to, a value greater than or equal to 0 and less than or equal to 1.
In some embodiments of present inventive concept, as illustrated in
The gray domain scale factor determiner 250 may receive the luminance domain scale factor LDSF from the luminance domain scale factor determiner 240, may convert the luminance domain scale factor LDSF into a gray domain scale factor GDSF, and may output the gray domain scale factor GDSF as the current control value CCV. In some embodiments of the present inventive concept, the current control value CCV, or the gray domain scale factor GDSF may have a value greater than or equal to 0 and less than or equal to 1.
In other embodiments of the present inventive concept, as illustrated in
Referring to
In some embodiments of the present inventive concept, a gray-luminance converter 210 may convert gray levels represented by pixel data PXD included in the K-th line data into pixel luminances PXLUM for the K-th pixel row, and a line luminance calculator 220 may calculate a line luminance LLUM for the K-th pixel row by summing the pixel luminances PXLUM for the K-th pixel row (S640). An average luminance level determiner 230 may store the line luminance LLUM for the K-th pixel row in a FIFO manner (S650). For example, the average luminance level determiner 230 may remove the line luminance LLUM for the K-th pixel row stored in the previous frame period while storing the line luminance LLUM for the K-th pixel row in the current frame period. Further, the panel driver 120 may sequentially receive the first through the N-th line data LD1 through LDN for first through N-th pixel rows PXR1 through PXRN in each frame period, and the average luminance level determiner 230 may maintain N line luminances LLUM by storing the N line luminances LLUM for the first through the N-th pixel rows PXR1 through PXRN in the FIFO manner. The average luminance level determiner 230 may determine an average panel luminance level APL based on the N line luminances LLUM for the first through the N-th pixel rows PXR1 through PXRN (S660). A luminance domain scale factor determiner 240 may determine a luminance domain scale factor LDSF corresponding to the average panel luminance level APL (S670). A gray domain scale factor determiner 250 may convert the luminance domain scale factor LDSF into a gray domain scale factor GDSF, and may output the gray domain scale factor GDSF as the current control value CCV for the (K+1)-th pixel row (S680).
Thereafter, the panel driver 120 may receive the (K+1)-th line data for the (K+1)-th pixel row in the current frame period (S610), may correct the (K+1)-th line data based on the current control value CCV for the (K+1)-th pixel row determined when the K-th line data are received in the current frame period (S620), and may drive the (K+1)-th pixel row based on the corrected (K+1)-th line data (S630). Further, when the (K+1)-th line data for the (K+1)-th pixel row are received, the panel driver 120 may determine a current control value CCV for a (K+2)-th pixel row based on the first line data LD1 through the (K+1)-th line data received in the current frame period and (K+2)-th line data through the N-th line data LDN received in the previous frame period (S640 through S680).
This way, the panel driver 120 may sequentially receive the first through the N-th line data LD1 through LDN for the first through the N-th pixel rows PXR1 through PXRN in each frame period (S610), may correct current line data for a current pixel row based on a current control value CCV determined when previous line data for a previous pixel row are received (S620), and may sequentially drive the first through the N-th pixel rows PXR1 through PXRN based on the corrected first through N-th line data LD1 through LDN (S630). Further, the panel driver 120 may determine a current control value CCV for a next pixel row when the current line data for the current pixel row are received (S640 through S680), and may apply the current control value CCV to next line data for the next pixel row (S620). Thus, in the method of operating the display device 100 according to embodiments of the present inventive concept, there may be a delay of only one line or only one pixel row between determining the current control value CCV and applying the current control value CCV, and an overcurrent or a rush current caused by the delay between determining the current control value CCV and applying the current control value CCV may be prevented.
Referring to
The gray-luminance converter 210 may convert gray levels represented by pixel data PXD included in line data LD for each pixel row into pixel luminances PXLUM for each pixel row. The line luminance calculator 220 may calculate a line luminance LLUM for each pixel row by summing the pixel luminances PXLUM for each pixel row. The average luminance level determiner 230 may store line luminances LLUM for first through N-th pixel rows in a FIFO manner, and may determine an average panel luminance level APL based on the line luminances LLUM for the first through the N-th pixel rows. The luminance domain scale factor determiner 240 may determine a luminance domain scale factor LDSF corresponding to the average panel luminance level APL.
The scaled panel luminance calculator 260 may multiply the line luminances LLUM for the first through the N-th pixel rows by luminance domain scale factors LDSF for the first through the N-th pixel rows, respectively, and may calculate a scaled panel luminance SPL by summing results of the multiplication. For example, the luminance domain scale factor determiner 240 may output the luminance domain scale factor LDSF for a current pixel row when line data LD for a previous pixel row are received, the line luminance calculator 220 may output the line luminance LLUM for the current pixel row when the line data LD for the current pixel row are received, and the scaled panel luminance calculator 260 may multiply the line luminance LLUM for the current pixel row by the luminance domain scale factor LDSF for the current pixel row. Further, the luminance domain scale factor determiner 240 may output the luminance domain scale factor LDSF for a next pixel row when the line data LD for the current pixel row are received, the line luminance calculator 220 may output the line luminance LLUM for the next pixel row when the line data LD for the next pixel row are received, and the scaled panel luminance calculator 260 may multiply the line luminance LLUM for the next pixel row by the luminance domain scale factor LDSF for the next pixel row. This way, the scaled panel luminance calculator 260 may store N multiplication results for the first through the N-th pixel rows in a FIFO manner, and may calculate the scaled panel luminance SPL by summing the N multiplication results when each line data LD are received.
The overcurrent protector 270 may receive the scaled panel luminance SPL from the scaled panel luminance calculator 260, and may compare the scaled panel luminance SPL with a panel luminance limit value. When the scaled panel luminance SPL is less than or equal to the panel luminance limit value, the overcurrent protector 270 may output the luminance domain scale factor LDSF generated by the luminance domain scale factor determiner 240 as an overcurrent-protected scale factor OCPSF. Alternatively, when the scaled panel luminance SPL exceeds the panel luminance limit value, the overcurrent protector 270 may generate the overcurrent-protected scale factor OCPSF by decreasing the luminance domain scale factor LDSF output from the luminance domain scale factor determiner 240.
The gray domain scale factor determiner 250′ may convert the overcurrent-protected scale factor OCPSF output from the overcurrent protector 270 into a gray domain scale factor GDSF, and may output the gray domain scale factor GDSF as a current control value CCV.
In some embodiments of the present inventive concept, in a case where the scaled panel luminance SPL exceeds the panel luminance limit value when the line data LD for the current pixel row are received, the overcurrent protector 270 may determine the overcurrent-protected scale factors OCPSF for pixel rows from the next pixel row to the last pixel row such that the current control values CCV for the pixel rows may become a minimum current control value. In some embodiments of the present inventive concept, the minimum current control value may be, but is not limited to, about 0. For example, as illustrated in
In other embodiments of the present inventive concept, in a case where the scaled panel luminance SPL exceeds the panel luminance limit value when the line data LD for the current pixel row are received, the overcurrent protector 270 may determine the overcurrent-protected scale factors OCPSF for the pixel rows from the next pixel row to the last pixel row such that the current control values CCV for the pixel rows are gradually decreased to a target current control value. In some embodiments of the present inventive concept, the target current control value may be a current control value CCV corresponding to the white image 710. For example, the target current control value may be, but is not limited to, about 0.2. For example, as illustrated in
A method illustrated in
Referring to
Further, when each line data LD are received, a scaled panel luminance calculator 260 may multiply line luminances LLUM for the first through the N-th pixel rows PXR1 through PXRN by luminance domain scale factors LDSF for the first through the N-th pixel rows PXR1 through PXRN, respectively, and may calculate a scaled panel luminance SPL by summing results of the multiplication (S672). For example, the scaled panel luminance calculator 260 may receive the line luminances LLUM from a line luminance calculator 220 and the luminance domain scale factors LDSF from a luminance domain scale factor determiner 240. When the scaled panel luminance SPL is less than or equal to the panel luminance limit value (S674: NO), a gray domain scale factor determiner 250′ may output, as the current control value CCV, a gray domain scale factor GDSF corresponding to a luminance domain scale factor LDSF generated by a luminance domain scale factor determiner 240 (S680).
Alternatively, when the scaled panel luminance SPL exceeds the panel luminance limit value (S674: YES), an overcurrent protector 270 may decrease the luminance domain scale factor LDSF to a minimum luminance domain scale factor (e.g., of about 0) corresponding to a minimum current control value (e.g., of about 0), and may output the minimum luminance domain scale factor as an overcurrent-protected scale factor OCPSF until a current frame period ends (S676). The gray domain scale factor determiner 250′ may convert the minimum luminance domain scale factor into a gray domain scale factor GDSF, and may output the minimum current control value as the current control value CCV (S680).
For example, as illustrated in
A method illustrated in
Referring to
Further, when each line data LD are received, a scaled panel luminance calculator 260 may multiply line luminances LLUM for the first through the N-th pixel rows PXR1 through PXRN by luminance domain scale factors LDSF for the first through the N-th pixel rows PXR1 through PXRN, respectively, and may calculate a scaled panel luminance SPL by summing results of the multiplication (S672). When the scaled panel luminance SPL is less than or equal to the panel luminance limit value (S674: NO), a gray domain scale factor determiner 250′ may output, as the current control value CCV, a gray domain scale factor GDSF corresponding to a luminance domain scale factor LDSF generated by a luminance domain scale factor determiner 240 (S680).
Alternatively, when the scaled panel luminance SPL exceeds the panel luminance limit value (S674: YES), an overcurrent protector 270 may gradually decrease the luminance domain scale factor LDSF to a target luminance domain scale factor corresponding to a target current control value (eg., of about 0.2), and may output the gradually decreased luminance domain scale factor as an overcurrent-protected scale factor OCPSF until a current frame period ends (S678). The gray domain scale factor determiner 250′ may convert the gradually decreased luminance domain scale factor into a gray domain scale factor GDSF, and may output the current control value CCV that is gradually decreased to the target current control value (S680).
For example, as illustrated in
Referring to
The processor 1110 may perform various computing functions or tasks. The processor 1110 may be an application processor (AP), a micro processor, a central processing unit (CPU), etc. The processor 1110 may be coupled to other components via an address bus, a control bus, a data bus, etc. Further, in some embodiments of the present inventive concept, the processor 1110 may be further coupled to an extended bus such as a peripheral component interconnection (PCI) bus.
The memory device 1120 may store data for operations 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 resistance 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.
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 supply power for operations of the electronic device 1100. The display device 1160 may be coupled to other components through the buses or other communication links.
In the display device 1160, when K-th line data for a K-th pixel row are received, a current control value for a (K+1)-th pixel row may be determined based on first through K-th line data received in a current frame period and (K+1)-th through N-th line data received in a previous frame period, and (K+1)-th line data may be corrected based on the current control value. Accordingly, an overcurrent caused by a delay between determining the current control value and applying the current control value may be prevented.
Embodiments of the present inventive concept may be applied any electronic device 1100 including the display device 1160. For example, the embodiments may be applied to a television (TV), a digital TV, a three-dimensional (3D) TV, a smart phone, a wearable electronic device, a tablet computer, a mobile phone, a personal computer (PC), a home appliance, a laptop computer, a personal digital assistant (PDA), a portable multimedia player (PMP), a digital camera, a music player, a portable game console, a navigation device, etc.
The foregoing is illustrative of embodiments of the present inventive concept and is not to be construed as limiting thereof. Although a few embodiments have been described, those skilled in the art will readily appreciate that many modifications are possible without departing from the scope of the present inventive concept. Accordingly, all such modifications are intended to be included within the scope of the present inventive concept as set forth in the claims.
Number | Date | Country | Kind |
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10-2021-0157564 | Nov 2021 | KR | national |