This application claims priority under 35 USC § 119 to Korean Patent Application No. 10-2019-0056399, filed on May 14, 2019 in the Korean Intellectual Property Office (KIPO), the contents of which are incorporated by reference herein in its entirety.
Example embodiments relate generally to a display device. More particularly, embodiments of the present inventive concept relate to a display device that prevents a product liability (PL) accident that can occur as an overcurrent flows in a display panel.
Display devices are found in televisions, computers, mobile electronics, and automobiles, among other examples. Automotive display devices can display images related to radio control, climate control, speed, navigation or diagnostics. Some display devices are susceptible to overcurrent, leading to possible display damages and safety concerns.
Overcurrent is a current load in excess of specific safety ratings that can lead to a circuit overload, short circuit, or a ground fault. The result of overcurrent can be an excessive amount of heat in a display, increasing fire or damage risk to the display panel. For example, excessive heat to a display panel can cause a display panel to be non-operational, increasing the risk of vehicle accidents. Additionally, if heat is very high, there are possible fire risks, putting life in immediate danger. Therefore, there is an opportunity to improve the design of the display device to prevent vehicle accidents due to the damages of the display panel, while continuously operating the display panel.
Some example embodiments provide a display device that can prevent damages of a display panel and/or a product liability accident due to the damages of the display panel while continuously operating the display panel when an overcurrent flows in the display panel.
According to an aspect of example embodiments, a display device may include a display panel configured to display an image, a display panel driving circuit configured to drive the display panel by generating a gate signal based on a clock signal, a first driving voltage corresponding to a gate-on voltage, and a second driving voltage corresponding to a gate-off voltage, by generating a data signal based on input data, and by providing the gate signal and the data signal to the display panel, a driving control circuit configured to control the display panel driving circuit by providing the clock signal and the input data to the display panel driving circuit and by providing at least one control signal to the display panel driving circuit, a power management integrated circuit configured to provide the first driving voltage and the second driving voltage to the display panel driving circuit through a first output terminal and a second output terminal, respectively, and a display panel protection circuit configured to monitor the first driving voltage of the first output terminal, to determine at least one frame following a current frame as a masking frame according to a masking ratio when the first driving voltage is out of a first reference voltage range, and to prevent the driving control circuit from providing the clock signal and the input data to the display panel driving circuit during the masking frame.
In example embodiments, the display panel protection circuit may determine whether the driving control circuit is to provide the clock signal and the input data to the display panel driving circuit by monitoring the first driving voltage in normal frames during which the image is displayed.
In example embodiments, the masking ratio may indicate a ratio of a number of the masking frames during a period of a masking driving to a number of normal frames that during the period. In addition, the masking ratio may be stored in a mapping table form in a memory device and may be referred to by the display panel protection circuit.
In example embodiments, the masking ratio may be constant regardless of a magnitude of the first driving voltage. In example embodiments, the masking ratio may be changed according to a magnitude of the first driving voltage.
In example embodiments, the masking ratio may increase as an amount by which the first driving voltage is out of the first reference voltage range increases, and a driving frequency of the display panel may decrease as the masking ratio increases.
In example embodiments, the masking ratio may decrease as an amount by which the first driving voltage is out of the first reference voltage range decreases, and a driving frequency of the display panel may increase as the masking ratio decreases.
According to another aspect of example embodiments, a display device may include a display panel configured to display an image, a display panel driving circuit configured to drive the display panel by generating a gate signal based on a clock signal, a first driving voltage corresponding to a gate-on voltage, and a second driving voltage corresponding to a gate-off voltage, by generating a data signal based on input data, and by providing the gate signal and the data signal to the display panel, a driving control circuit configured to control the display panel driving circuit by providing the clock signal and the input data to the display panel driving circuit and by providing at least one control signal to the display panel driving circuit, a power management integrated circuit configured to provide the first driving voltage and the second driving voltage to the display panel driving circuit through a first output terminal and a second output terminal, respectively, and a display panel protection circuit configured to monitor the second driving voltage of the second output terminal, to determine at least one frame following a current frame as a masking frame according to a masking ratio when the second driving voltage is out of a second reference voltage range, and to prevent the driving control circuit from providing the clock signal and the input data to the display panel driving circuit during the masking frame.
In example embodiments, the display panel protection circuit may determine whether the driving control circuit is to provide the clock signal and the input data to the display panel driving circuit by monitoring the second driving voltage in normal frames during which the image is displayed.
In example embodiments, the masking ratio may indicate a ratio of a number of the masking frames during a period of a masking driving to a number of normal frames that during the period. In addition, the masking ratio may be stored in a mapping table form in a memory device and may be referred to by the display panel protection circuit.
In example embodiments, the masking ratio may be constant regardless of a magnitude of the second driving voltage. In example embodiments, the masking ratio may be changed according to a magnitude of the second driving voltage.
In example embodiments, the masking ratio may increase as an amount by which the second driving voltage is out of the second reference voltage range increases, and a driving frequency of the display panel may decrease as the masking ratio increases.
In example embodiments, the masking ratio may decrease as an amount by which the second driving voltage is out of the second reference voltage range decreases, and a driving frequency of the display panel may increase as the masking ratio decreases.
According to still another aspect of example embodiments, a display device may include a display panel configured to display an image, a display panel driving circuit configured to drive the display panel by generating a gate signal based on a clock signal, a first driving voltage corresponding to a gate-on voltage, and a second driving voltage corresponding to a gate-off voltage, by generating a data signal based on input data, and by providing the gate signal and the data signal to the display panel, a driving control circuit configured to control the display panel driving circuit by providing the clock signal and the input data to the display panel driving circuit and by providing at least one control signal to the display panel driving circuit, a power management integrated circuit configured to provide the first driving voltage and the second driving voltage to the display panel driving circuit through a first output terminal and a second output terminal, respectively, and a display panel protection circuit configured to monitor at least one selected from a first current flowing through the first output terminal and a second current flowing through the second output terminal, to determine at least one frame following a current frame as a masking frame according to a masking ratio when the at least one selected from the first current and the second current is judged to be an overcurrent, and to prevent the driving control circuit from providing the clock signal and the input data to the display panel driving circuit during the masking frame.
In example embodiments, the display panel protection circuit may determine whether the driving control circuit is to provide the clock signal and the input data to the display panel driving circuit by monitoring the at least one selected from the first current and the second current in normal frames during which the image is displayed.
In example embodiments, the masking ratio may indicate a ratio of a number of the masking frames during a period of a masking driving to a number of a normal frame that is implemented during the period. In addition, the masking ratio may be stored in a mapping table form in a memory device and may be referred to by the display panel protection circuit.
In example embodiments, the masking ratio may be constant regardless of a magnitude of the overcurrent. In example embodiments, the masking ratio may be changed according to a magnitude of the overcurrent.
In example embodiments, the masking ratio may increase as the overcurrent increases, and a driving frequency of the display panel may decrease as the masking ratio increases. In addition, the masking ratio may decrease as the overcurrent decreases, and the driving frequency of the display panel may increase as the masking ratio decreases.
Therefore, a display device according to example embodiments may monitor a driving voltage (e.g., a first driving voltage corresponding to a gate-on voltage and/or a second driving voltage corresponding to a gate-off voltage) that is provided from a power management integrated circuit to a display panel driving circuit, may determine at least one frame following a current frame as a masking frame according to a masking ratio when the driving voltage is out of a specific reference voltage range, and may control a driving control circuit not to provide a clock signal and input data to the display panel driving circuit during the masking frame. Thus, the display device may minimize damages of the display panel due to an overcurrent flowing in the display panel while continuously displaying an image on the display panel by reducing only the number of a normal frame (i.e., reducing only a driving frequency of the display panel) according to the masking ratio when the overcurrent flows in the display panel. As a result, the display device may prevent the damages of the display panel and/or a product liability accident due to the damages of the display panel while continuously operating the display panel when the overcurrent flows in the display panel.
In addition, a display device according to example embodiments may monitor a current flowing between a power management integrated circuit and a display panel driving circuit, may determine at least one frame following a current frame as a masking frame according to a masking ratio when the current is out of a specific reference current range (i.e., when the current is judged to be an overcurrent), and may control a driving control circuit not to provide a clock signal and input data to the display panel driving circuit during the masking frame. Thus, the display device may minimize damages of the display panel due to an overcurrent flowing in the display panel while continuously displaying an image on the display panel by reducing only the number of a normal frame (i.e., reducing only a driving frequency of the display panel) according to the masking ratio when the overcurrent flows in the display panel. As a result, the display device may prevent the damages of the display panel and/or a product liability accident due to the damages of the display panel while continuously operating the display panel when the overcurrent flows in the display panel.
According to another aspect of the inventive concept, a method of operating a display device is described. The method may include monitoring electric power provided to a display panel; identifying an overcurrent condition based on the monitoring, wherein the overcurrent condition comprises a current exceeding a current threshold or a voltage exceeding a voltage threshold; and reducing a display frequency of the display panel based on identifying the overcurrent condition.
In some examples, reducing the display frequency further comprises identifying a masking ratio based on the overcurrent condition; identifying one or more masking frames based on the masking ratio; and preventing a signal from being provided to the display panel during the one or more masking frames.
Illustrative, non-limiting example embodiments will be more clearly understood from the following detailed description in conjunction with the accompanying drawings.
When an overcurrent flows in a display panel of a display device, the display panel may be damaged, and thus a product liability accident such as an explosion, ignition, or fire of the display panel may occur due to excessive heat of the display panel. In some cases, a display device in an overcurrent event performs a function to disable the display panel. For example, if the display unit of a vehicle does not operate due to an overcurrent event, a vehicle accident may occur. Additionally, a vehicle display may also ignite and injury a user if the display is not disabled.
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 a plurality of pixels 111. The display panel 110 may display an image based on color lights output from the pixels 111. In an example embodiment, the pixels 111 may include red color display pixels that output a red color light, green color display pixels that output a green color light, and blue color display pixels that output a blue color light. In another example embodiment, the pixels 111 may include red color display pixels that output a red color light, green color display pixels that output a green color light, blue color display pixels that output a blue color light, and white color display pixels that output a white color light. The pixels 111 may be arranged in various forms (e.g., a matrix form, etc.) in the display panel 110. The display panel driving circuit 120 may drive the display panel 110. To this end, the display panel driving circuit 120 may include a gate driver, a data driver, etc.
The display panel 110 may be electrically connected to the gate driver via a plurality of gate-lines and to the data driver via a plurality of data-lines. The gate driver may provide a gate signal GS to the display panel 110 via the gate-lines. The gate driver may generate the gate signal GS based on a clock signal CLK, a first driving voltage VGH corresponding to a gate-on voltage, and a second driving voltage VGL corresponding to a gate-off voltage.
The data driver may provide a data signal DS to the display panel 110 via the data-lines. The data driver may generate the data signal DS based on input data SDI. The display panel driving circuit 120 may drive the display panel 110 by providing the gate signal GS and the data signal DS to the display panel 110. The driving control circuit 130 may control the display panel driving circuit 120 by providing at least one control signal CTL to the display panel driving circuit 120. For example, the driving control circuit 130 may control the gate driver, the data driver, etc by generating and providing at least one control signal CTL to the gate driver, the data driver, etc.
In some example embodiments, the driving control circuit 130 may perform a processing function (e.g., image data compensation, etc) on image data input from an external component. In addition, the driving control circuit 130 may be integrated with the display panel driving circuit 120 as one integrated chip. The driving control circuit 130 may provide the clock signal CLK and the input data SDI to the display panel driving circuit 120. For example, the driving control circuit 130 may provide the clock signal CLK to the gate driver to generate the gate signal GS. The gate driver may be included in the display panel driving circuit 120. Additionally, the driving control circuit 130 may provide the input data SDI to the data driver to generate the data signal DS. The data driver may be included in the display panel driving circuit 120.
The power management integrated circuit 140 may provide the display panel 110 with power POW for operations of the display panel 110. The power management integrated circuit 140 may provide the first driving voltage VGH corresponding to the gate-on voltage to the display panel driving circuit 120 through a first output terminal and may provide the second driving voltage VGL corresponding to the gate-off voltage to the display panel driving circuit 120 through a second output terminal. Thus, the gate driver included in the display panel driving circuit 120 may generate the gate signal GS using the first driving voltage VGH, the second driving voltage VGL, the clock signal CLK. The first driving voltage VGH may be a constant-voltage. The second driving voltage VGL may also be a constant-voltage. Therefore, a first voltage level of the gate signal GS (i.e., the gate-on voltage) may be a voltage level of the first driving voltage VGH (e.g., a positive voltage level). Additionally, a second voltage level of the gate signal GS (i.e., the gate-off voltage) may be a voltage level of the second driving voltage VGL (e.g., a negative voltage level or a ground voltage level).
When the overcurrent flows in the display panel 110, the display panel protection circuit 150 may minimize damages of the display panel 110 due to an overcurrent flowing in the display panel 110 while continuously displaying an image on the display panel 110 by reducing, for example, a driving frequency of the display panel 110. The luminance of the display panel 110 may be lowered as the number of normal frames is reduced. Generally, when a short circuit and the like of wirings included in the display panel 110 occur, the overcurrent may flow in the display panel 110. Thus, due to the overcurrent flows between the power management integrated circuit 140 and the display panel driving circuit 120, the display panel protection circuit 150 may determine whether the overcurrent flows in the display panel 110 by monitoring whether the overcurrent flows between the power management integrated circuit 140 and the display panel driving circuit 120 (i.e., indicated by MTS). In addition, when the overcurrent flows in the display panel 110 as the short circuit and the like of the wirings included in the display panel 110 occur, the first driving voltage VGH and/or the second driving voltage VGL that the power management integrated circuit 140 provides to the display panel driving circuit 120 may be changed.
For example, a voltage level of the first driving voltage VGH having a positive voltage level may be decreased, and a voltage level of the second driving voltage VGL having a negative voltage level or a ground voltage level may be increased. Thus, the display panel protection circuit 150 may determine whether the overcurrent flows in the display panel 110 by monitoring whether the first driving voltage VGH and/or the second driving voltage VGL that the power management integrated circuit 140 provides to the display panel driving circuit 120 may be changed (i.e., indicated by MTS).
In example embodiments, the display panel protection circuit 150 may determine a portion of frames as a masking frame MF when the overcurrent flows in the display panel 110 and may control the driving control circuit 130 not to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 during the masking frame MF (i.e., indicated by PCTL). As a result, the damages of the display panel 110 may be prevented due to no current flows in the display panel 110 during the masking frame MF. Because a portion of charges stored in a storage capacitor of the pixel 111 during the normal frame NF is maintained during the masking frame MF, a fully black image may not be displayed on the display panel 110 during the masking frame MF.
In an example embodiment, the display panel protection circuit 150 may monitor the first driving voltage VGH of the first output terminal of the power management integrated circuit 140. Additionally, the display panel protection circuit 150 may determine at least one frame following a current frame as the masking frame MF according to a masking ratio when the first driving voltage VGH is outside of the first reference voltage range. The display panel protection circuit 150 may also control the driving control circuit 130 not to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 during the masking frame MF. An embodiment will be described in detail with reference to
In another example embodiment, the display panel protection circuit 150 may monitor the second driving voltage VGL of the second output terminal of the power management integrated circuit 140. Additionally, the display panel protection circuit 150 may determine at least one frame following a current frame as the masking frame MF according to a masking ratio when the second driving voltage VGL is outside of the second reference voltage range. The display panel protection circuit 150 may also control the driving control circuit 130 not to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 during the masking frame MF. An embodiment will be described in detail with reference to
In still another example embodiment, the display panel protection circuit 150 may monitor at least one selected from a first current flowing through the first output terminal of the power management integrated circuit 140 and a second current flowing through the second output terminal of the power management integrated circuit 140. Additionally, the display panel protection circuit 150 may determine at least one frame following a current frame as the masking frame MF according to a masking ratio when the at least one selected from the first current and the second current is judged to be the overcurrent. The display panel protection circuit 150 may also control the driving control circuit 130 not to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 during the masking frame MF. An embodiment will be described in detail with reference to
The display panel protection circuit 150 may determine at least one frame following a current frame as the masking frame MF, according to the masking ratio, when the overcurrent flows in the display panel 110. The display panel protection circuit 150 may also control the display panel 110 not to operate by controlling the clock signal CLK and the input data SDI not to be provided to the display panel driving circuit 120 during the masking frame MF. As a result, since the number of normal frames NF is reduced by the number of masking frames MF, the damages of the display panel 110 may be minimized. Damage of the display panel 110 may be minimized by reducing the number of times the display panel 110 displays an image. Thus, the display panel 110 may safely and continuously operate at a reduced driving frequency.
As described above, the display panel protection circuit 150 may reduce the number of normal frames NF by determining at least one frame following a current frame as the masking frame MF according to the masking ratio when the overcurrent flows in the display panel 110. The display panel protection circuit 150 may determine whether the driving control circuit 130 is to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 by monitoring whether the overcurrent flows in the display panel 110 in each normal frame NF that implements an image. In the masking frame MF, the display panel protection circuit 150 may not monitor whether the overcurrent flows in the display panel 110. In an example embodiment, the masking ratio may indicate a ratio of the number of the masking frames MF implemented during a period PR of a masking driving to the number of normal frames NF implemented during a period PR of the masking driving.
Thus, a method of operating a display device may include monitoring electric power provided to a display panel 110; identifying an overcurrent condition based on the monitoring, wherein the overcurrent condition comprises a current exceeding a current threshold or a voltage exceeding a voltage threshold; and reducing a display frequency of the display panel 110 based on identifying the overcurrent condition.
In some examples, reducing the display frequency further comprises identifying a masking ratio based on the overcurrent condition; identifying one or more masking frames MF based on the masking ratio; and preventing a signal from being provided to the display panel 110 during the one or more masking frames MF.
For example,
For example,
For example,
In example embodiments, the masking ratio may be stored in a mapping table form in a memory device and may be referred to by the display panel protection circuit 150. For example, the memory device that stores the masking ratio may be located inside the display panel protection circuit 150. For example, the memory device that stores the masking ratio may be located outside the display panel protection circuit 150. In an example embodiment, when the overcurrent flows in the display panel 110, the masking ratio may be constant, regardless of the magnitude of the overcurrent. For example, when the display panel protection circuit 150 monitors the first driving voltage VGH that the power management integrated circuit 140 provides to the display panel driving circuit 120, the masking ratio may be constant regardless of the magnitude of the first driving voltage VGH. For example, when the display panel protection circuit 150 monitors the second driving voltage VGL that the power management integrated circuit 140 provides to the display panel driving circuit 120, the masking ratio may be constant regardless of the magnitude of the second driving voltage VGL. For example, the masking ratio may be constant, regardless of the magnitude of the overcurrent, when the display panel protection circuit 150 monitors an overcurrent flowing between the power management integrated circuit 140 and the display panel driving circuit 120. In another example embodiment, the masking ratio may be changed according to a magnitude of the overcurrent when the overcurrent flows in the display panel 110. For example, when the display panel protection circuit 150 monitors the first driving voltage VGH that the power management integrated circuit 140 provides to the display panel driving circuit 120, the masking ratio may be changed according to a magnitude of the first driving voltage VGH. For example, when the display panel protection circuit 150 monitors the second driving voltage VGL that the power management integrated circuit 140 provides to the display panel driving circuit 120, the masking ratio may be changed according to a magnitude of the second driving voltage VGL. For example, the masking ratio may be changed according to a magnitude of the overcurrent when the display panel protection circuit 150 monitors an overcurrent flowing between the power management integrated circuit 140 and the display panel driving circuit 120.
In an example embodiment, the masking ratio may increase as an overcurrent flowing in the display panel 110 increases, and the driving frequency of the display panel 110 may decrease as the masking ratio increases. In addition, the masking ratio may decrease as an overcurrent flowing in the display panel 110 decreases, and the driving frequency of the display panel 110 may increase as the masking ratio decreases. The masking ratio may be stored in the mapping table form in the memory device. For example, as illustrated in
When the detection value that the display panel protection circuit 150 detects belongs to a first range RANGE(1), the display panel protection circuit 150 may determine that the overcurrent does not flow in the display panel 110. Thus, the display panel protection circuit 150 may not perform the masking driving (i.e., indicated by OFF). In other words, the display panel protection circuit 150 may not perform the masking driving when the register data is ‘00000’. In addition, when the detection value that the display panel protection circuit 150 detects belongs to a second range RANGE(2), a third range RANGE(3), and a fourth range RANGE(4), the display panel protection circuit 150 may determine that the overcurrent flows in the display panel 110. Thus, the display panel protection circuit 150 may perform the masking driving by setting the masking ratio to be 1:1 when the detection value belongs to the second range RANGE(2). Additionally, the display panel protection circuit 150 may perform the masking driving by setting the masking ratio to be 1:2 when the detection value belongs to the third range RANGE(3). The display panel protection circuit 150 may also perform the masking driving by setting the masking ratio to be 1:3 when the detection value belongs to the fourth range RANGE(4). In other words, the display panel protection circuit 150 may perform the masking driving by setting the masking ratio to be 1:1 when the register data is ‘00001’. Additionally, the display panel protection circuit 150 may perform the masking driving by setting the masking ratio to be 1:2 when the register data is ‘00010’ and may perform the masking driving by setting the masking ratio to be 1:3 when the register data is ‘00011’.
Further, when the detection value that the display panel protection circuit 150 detects belongs to a (32)th range RANGE(32), the display panel protection circuit 150 may determine that a serious overcurrent flows in the display panel 110. Thus, the display panel protection circuit 150 may shut down the display panel immediately (i.e., indicated by SHUT DOWN) without performing the masking driving to protect the display panel 110 quickly. In other words, the display panel protection circuit 150 may shut down (or power off) the display panel driving circuit 120 when the register data is ‘11111’. Since the setting of the masking ratio illustrated in
In brief, the display device 100 may monitor a driving voltage provided from the power management integrated circuit 140 to the display panel driving circuit 120. Monitoring a driving voltage may include the first driving voltage VGH corresponding to the gate-on voltage and/or the second driving voltage VGL corresponding to the gate-off voltage. Additionally, the display device 100 may determine at least one frame following a current frame as the masking frame MF, according to the masking ratio, when the driving voltage is outside of a reference voltage range. The display device 100 may also control the driving control circuit 130 not to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 during the masking frame MF.
In addition, the display device 100 may monitor a current flowing between the power management integrated circuit 140 and the display panel driving circuit 120 (e.g., the first current flowing through the first output terminal of the power management integrated circuit 140 and/or the second current flowing through the second output terminal of the power management integrated circuit 140). Additionally, the display device 100 may determine at least one frame following a current frame as the masking frame MF, according to the masking ratio, when the current is outside of a reference current range. The display device 100 may also control the driving control circuit 130 not to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 during the masking frame MF. Thus, the display device 100 may minimize the damages of the display panel 110 due to the overcurrent flowing in the display panel 110 while continuously displaying an image on the display panel 110. The display device 100 may minimize the damages of the display panel 110 by reducing the number of normal frames, according to the masking ratio, when the overcurrent flows in the display panel 110. Reducing the number of normal frames NF may include reducing the driving frequency of the display panel 110. As a result, the display device 100 may prevent the damages of the display panel 110 and/or the product liability accident due to the damages of the display panel 110 while continuously operating the display panel 110 when the overcurrent flows in the display panel 110.
Thus, when the display device 100 is implemented in a vehicle, the display device 100 may prevent a situation in which driving the vehicle becomes difficult as the display panel 110 may not operate properly. Additionally, the display device 100 may prevent a product liability situation, such as an explosion, ignition, or fire, as the display panel 110 operates under poor conditions.
Referring to
Conversely, when the first driving voltage VGH is within the first reference voltage range, the display panel protection circuit 150 may determine that the first driving voltage VGH is within a normal range and may perform the normal driving that implements each frame (S140). In example embodiments, the first reference voltage range (e.g., a range between REF and REV1) corresponding to the normal range of the first driving voltage VGH may be set in various ways according to requirements. In addition, the display panel protection circuit 150 may determine whether the driving control circuit 130 is to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 by monitoring the first driving voltage VGH in each normal frame NF during which an image is displayed.
For example, as illustrated in
Subsequently, the display panel protection circuit 150 may determine that the first driving voltage VGH is outside of the first reference voltage range (e.g., the range between REF and REV1) in a third frame 3F (i.e., indicated by DEC2). Thus, the display panel protection circuit 150 may perform the masking driving due to the determination that an overcurrent flows in the display panel 110 during the third frame 3F. Since the first driving voltage VGH has a voltage level between the first voltage level REV1 and the second voltage level REV2, the display panel protection circuit 150 may determine a fourth frame 4F following a current frame (i.e., the third frame 3F) as the masking frame MF according to the masking ratio of 1:1.
Next, the display panel protection circuit 150 may determine that the first driving voltage VGH is outside of the first reference voltage range (e.g., the range between REF and REV1) in a fifth frame 5F (i.e., indicated by DEC3). Thus, the display panel protection circuit 150 may perform the masking driving due to the determination that an overcurrent flows in the display panel 110 during the fifth frame 5F. Since the first driving voltage VGH has a voltage level between the first voltage level REV1 and the second voltage level REV2, the display panel protection circuit 150 may determine a sixth frame 6F following a current frame (i.e., the fifth frame 5F) as the masking frame MF according to the masking ratio of 1:1. For example, the display panel protection circuit 150 may monitor the first driving voltage VGH in each normal frame NF among the first through sixth frames 1F through 6F. The display panel protection circuit 150 may also perform the masking driving based on the masking ratio of 1:1, which is determined according to a magnitude of the first driving voltage VGH. For example, the driving frequency of the display panel 110 is reduced to ½ of the normal driving frequency of the display panel 110.
Subsequently, the display panel protection circuit 150 may determine that the first driving voltage VGH is outside of the first reference voltage range (e.g., the range between REF and REV1) in a seventh frame 7F (i.e., indicated by DEC4). Thus, the display panel protection circuit 150 may perform the masking driving due to the determination that an overcurrent flows in the display panel 110 during the seventh frame 7F. Since the first driving voltage VGH has a voltage level lower than the second voltage level REV2, the display panel protection circuit 150 may determine an eighth frame 8F and a ninth frame 9F following a current frame (i.e., the seventh frame 7F) as the masking frame MF, according to the masking ratio of 1:2. Next, the display panel protection circuit 150 may determine that the first driving voltage VGH is outside of the first reference voltage range (e.g., the range between REF and REV1) in a tenth frame 10F (i.e., indicated by DEC5). Thus, the display panel protection circuit 150 may perform the masking driving due to the determination that an overcurrent flows in the display panel 110 during the tenth frame 10F. Since the first driving voltage VGH has a voltage level lower than the second voltage level REV2, the display panel protection circuit 150 may determine an eleventh frame 11F and a twelfth frame 12F following a current frame (i.e., the tenth frame 10F) as the masking frame MF, according to the masking ratio of 1:2. For example, the display panel protection circuit 150 may monitor the first driving voltage VGH in each normal frame NF among the seventh through twelfth frames 7F through 12F. The display panel protection circuit 150 may also perform the masking driving based on the masking ratio of 1:2 which is determined according to a magnitude of the first driving voltage VGH. For example, the driving frequency of the display panel 110 is reduced to ⅓ of the normal driving frequency of the display panel 110.
Although it is described above that an overcurrent flows in the display panel 110 during the first frame 1F, during the third frame 3F, during the fifth frame 5F, during the seventh frame 7F, and during the tenth frame 10F, it may be determined that an overcurrent does not flow in the display panel 110 at some detection times after the first detection time (i.e., DEC1). Overcurrent flows in the display panel 110 at certain detection times (i.e., DEC2, DEC3, DEC4, and DEC5) after the first detection time (i.e., DEC1) due to overcurrent flows in the display panel 110 from a short circuit of wirings included in the display panel 110.
Referring to
Conversely, when the second driving voltage VGL is within the second reference voltage range, the display panel protection circuit 150 may determine that the second driving voltage VGL is within a normal range and may perform the normal driving that implements each frame (S240). In example embodiments, the second reference voltage range (e.g., a range between REF and REV1) corresponding to the normal range of the second driving voltage VGL may be set in various ways according to requirements. In addition, the display panel protection circuit 150 may determine whether the driving control circuit 130 is to provide the clock signal CLK and the input data SDI to the display panel driving circuit 120 by monitoring the second driving voltage VGL in each normal frame NF during which an image is displayed.
For example, as illustrated in
Subsequently, the display panel protection circuit 150 may determine that the second driving voltage VGL is outside of the second reference voltage range (e.g., the range between REF and REV1) in a seventh frame 7F (i.e., indicated by DEC4). Thus, the display panel protection circuit 150 may perform the masking driving because it is determined that an overcurrent flows in the display panel 110 during the seventh frame 7F. Since the second driving voltage VGL has a voltage level higher than the second voltage level REV2, the display panel protection circuit 150 may determine an eighth frame 8F and a ninth frame 9F following a current frame (i.e., the seventh frame 7F) as the masking frame MF according to the masking ratio of 1:2. Next, the display panel protection circuit 150 may determine that the second driving voltage VGL is outside of the second reference voltage range (e.g., the range between REF and REV1) in a tenth frame 10F (i.e., indicated by DEC5). Thus, the display panel protection circuit 150 may perform the masking driving because it is determined that an overcurrent flows in the display panel 110 during the tenth frame 10F. Since the second driving voltage VGL has a voltage level higher than the second voltage level REV2, the display panel protection circuit 150 may determine an eleventh frame 11F and a twelfth frame 12F following a current frame (i.e., the tenth frame 10F) as the masking frame MF according to the masking ratio of 1:2. For example, the display panel protection circuit 150 may monitor the second driving voltage VGL in each normal frame NF among the seventh through twelfth frames 7F through 12F and may perform the masking driving based on the masking ratio of 1:2 which is determined according to a magnitude of the second driving voltage VGL (i.e., the driving frequency of the display panel 110 is reduced to ⅓ of the normal driving frequency of the display panel 110). Although it is described above that an overcurrent flows in the display panel 110 during the first frame 1F, during the third frame 3F, during the fifth frame 5F, during the seventh frame 7F, and during the tenth frame 10F, it may be determined that an overcurrent does not flow in the display panel 110 at some detection times after the first detection time (i.e., DEC1). However, because an overcurrent flows in the display panel 110 due to a short circuit and the like of wirings included in the display panel 110, it may be natural that an overcurrent flows in the display panel 110 at certain detection times (i.e., DEC2, DEC3, DEC4, and DEC5) after the first detection time (i.e., DEC1).
Referring to
For example, as illustrated in
Since the first current and/or the second current have a current level higher than the reference current level REF, the display panel protection circuit 150 may determine a sixth frame 6F following a current frame (i.e., the fifth frame 5F) as the masking frame MF according to the masking ratio of 1:1. Next, the display panel protection circuit 150 may determine that the first current and/or the second current is the overcurrent in a seventh frame 7F (i.e., indicated by DEC3). Thus, the display panel protection circuit 150 may perform the masking driving because it is determined that an overcurrent flows in the display panel 110 during the seventh frame 7F. Since the first current and/or the second current have a current level higher than the reference current level REF, the display panel protection circuit 150 may determine an eighth frame 8F following a current frame (i.e., the seventh frame 7F) as the masking frame MF according to the masking ratio of 1:1. For example, the display panel protection circuit 150 may monitor the first current and/or the second current in each normal frame NF and may perform the masking driving based on the masking ratio of 1:1. A masking ratio of 1:1 is determined according to a magnitude of the first current and/or the second current (i.e., the driving frequency of the display panel 110 is reduced to ½ of the normal driving frequency of the display panel 110). An overcurrent may flow in the display panel 110 at certain detection times (i.e., DEC2 and DEC3) after the first detection time (i.e., DEC1) when an overcurrent flows in the display panel 110 due to a short circuit and the like of wirings included in the display panel 110,
Referring to
The processor 1010 may perform various computing functions. The processor 1010 may be a microprocessor, a central processing unit (CPU), an application processor (AP), etc. The processor 1010 may be coupled to other components via an address bus, a control bus, a data bus, etc. Further, the processor 1010 may be coupled to an extended bus such as a peripheral component interconnection (PCI) bus. The memory device 1020 may store data for operations of the electronic device 1000. For example, the memory device 1020 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 DRAM device, etc. The storage device 1030 may include a solid-state drive (SSD) device, a hard disk drive (HDD) device, a CD-ROM device, etc. The I/O device 1040 may include an input device such as a keyboard, a keypad, a mouse device, a touch-pad, a touch-screen, etc, and an output device such as a printer, a speaker, etc. The power supply 1050 may provide power for operations of the electronic device 1000.
The display device 1060 may be coupled to other components via the buses or other communication links. In some example embodiments, the display device 1060 may be included in the I/O device 1040. As described above, the display device 1060 may minimize damages of a display panel due to an overcurrent flowing in the display panel while continuously displaying an image on the display panel by reducing the number of a normal frame (i.e., reducing a driving frequency of the display panel) according to a masking ratio when the overcurrent flows in the display panel.
The display device 1060 may include a display panel, a display panel driving circuit, a first driving voltage, a second driving voltage, a driving control circuit, a power management integrated circuit, and a display panel protection circuit. The display panel displays an image. The display panel driving circuit drives the display panel by generating a gate signal based on a clock signal. The first driving voltage corresponds to a gate-on voltage and a second driving voltage corresponds to a gate-off voltage. The first driving voltage and the second driving voltage generate a data signal based on input data and by providing the gate signal and the data signal to the display panel. The driving control circuit controls the display panel driving circuit by providing the clock signal and the input data to the display panel driving circuit and by providing at least one control signal to the display panel driving circuit. The power management integrated circuit provides the first driving voltage and the second driving voltage to the display panel driving circuit through a first output terminal and a second output terminal, respectively. The display panel protection circuit performs a masking driving on the display panel when an overcurrent flows in the display panel.
In an example embodiment, the display panel protection circuit may monitor a driving voltage provided from the power management integrated circuit to the display panel driving circuit. For example, the first driving voltage corresponding to the gate-on voltage and/or the second driving voltage corresponding to the gate-off voltage. Additionally, the display panel protection circuit may determine at least one frame following a current frame as the masking frame according to the masking ratio when the driving voltage is outside of a reference voltage range. The display panel protection circuit may also control the driving control circuit not to provide the clock signal and the input data to the display panel driving circuit during the masking frame.
In another example embodiment, the display panel protection circuit may monitor a current flowing between the power management integrated circuit and the display panel driving circuit. Additionally, the display panel protection circuit may determine at least one frame following a current frame as the masking frame according to the masking ratio when the current is outside of a reference current range (i.e., when the current is judged to be an overcurrent). The display panel protection circuit may also control the driving control circuit not to provide the clock signal and the input data to the display panel driving circuit during the masking frame. Since these are described above, a duplicated description related thereto will not be repeated.
The present inventive concept may be applied to a display device and an electronic device including the display device. For example, the present inventive concept may be applied to a car navigation system, a car display unit, a car side mirror, a car rear mirror, a cellular phone, a smartphone, a video phone, a smart pad, a smartwatch, a tablet PC, a television, a computer monitor, a laptop, a head-mounted display (HMD) device, etc.
The foregoing is illustrative of example embodiments and is not to be construed as limiting thereof. Although a few example embodiments have been described, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from the novel teachings and advantages of the present inventive concept. Accordingly, all such modifications are intended to be included within the scope of the present inventive concept as defined in the claims. Therefore, it is to be understood that the foregoing is illustrative of various example embodiments and is not to be construed as limited to the specific example embodiments disclosed and that modifications to the disclosed example embodiments, as well as other example embodiments, are intended to be included within the scope of the appended claims.
Number | Date | Country | Kind |
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10-2019-0056399 | May 2019 | KR | national |