KR102212208B1 - Data Driving Circuit Device for Display Device and Display Device having the same - Google Patents

Abstract

A data driving device for a display device and a display device including the same, comprising: a remote frame buffer, which is a still image data storage unit for storing still image data, in a data driving circuit of the display device. When a function such as PSR (Panel Self-Refresh) is activated while still image is output, power consumption compared to general PSR by additionally deactivating the operation of the transmitter of the timing controller and the receiver of the data driving circuit of the display device. There is an effect that can further reduce

Description

Data driving circuit device for display device and display device having the same

The present invention relates to a data driving device for a display device and a display device including the same. In particular, when a still image is displayed for a certain period of time, the power consumption of the display device can be reduced, for example, a panel self-refresh. -Refresh; hereinafter also referred to as'PSR'), a data driving device and a display device including the same.

As the information society develops, demands for display devices for displaying images are increasing in various forms, and in recent years, liquid crystal displays (LCDs), plasma display panels (PDPs), organic electric fields Various display devices such as an OLED (Organic Light Emitting Diode Display Device) are being used.

Such a display device includes a display panel, a gate driving circuit as a driving circuit for driving it, a timing controller (T-con), a data driving circuit, etc., and the display device includes an external application processor ( After receiving source data related to an image signal from an application processor (AP), the image is displayed by outputting it to the gate line and the data line of the display panel.

Meanwhile, as a standard technology that defines an interface method for connecting between chips and chips of electronic devices including display devices or between products and products, a Display Port (DP) interface established by the Video Electronics Standards Association (VESA) There is. This DP interface is an interface method that can be connected to one by integrating Low Voltage Differential Signaling (LVDS), an existing internal interface standard, and Digital Visual Interface (DVI), an external connection standard.

In addition, recently, VESA has additionally defined an embedded display port (eDP) standard as a new version of DP. This eDP is defined for electronic devices with built-in display devices such as notebook PCs, tablets, and smartphones. It is an interface standard. Among them, eDP version 1.3 uses panel self-refresh (PSR) technology to reduce system power consumption of devices including display devices and extend battery life in a portable device environment.

This PSR technology is a technology that can greatly increase the battery usage time in a portable PC environment by minimizing power consumption and displaying the screen as it is by utilizing the memory installed in the display.

The general PSR operation outline is as follows.

A display device capable of PSR operation includes a source unit and a sink unit, and the source unit indicates a system that controls the entire device, and includes an eDP transmitter, and the sink unit indicates a display panel unit including a display device. Includes a display.

The timing controller includes an eDP receiver and a remote frame buffer (hereinafter, referred to as'RFB'), and the source and sink communicate with each other through an eDP interface.

Such a display device activates the PSR function when a still image without a screen change is input for a certain period of time, and deactivates the PSR drive for moving pictures other than still images. When PSR drive is activated, still image data is transmitted from the eDP transmitter to the eDP receiver and then stored in the RFB.

Subsequently, the operating power of the source unit is turned off, and in this state, still image data stored in the RFB is applied to the display unit. Until the RFB is updated by the new still image data, the operating power of the source unit is maintained in an off state, and the display unit continuously displays the data previously stored in the RFB.

That is, when the PSR drive is activated, the same screen is automatically implemented by data stored in the RFB even when the operating power of the source unit is turned off. As a result, power consumption is reduced and battery usage time is increased.

As described above, in a device including a display panel, the source unit including the eDP transmitting unit becomes an application processor, and the sink unit including the eDP receiving unit and the remote frame buffer RFB becomes a timing controller.

Meanwhile, in the above-described configuration, the display unit generally includes a display panel such as an LCD or OLED, and a data driving circuit for providing a video source signal to a data line formed on the display panel.

Such a data driving circuit, also referred to as D-IC, receives a signal related to image data from a timing controller and generates a data output signal or a source output signal to be provided to the data line of the display panel based on the received signal to the corresponding data line. It performs the function of printing.

Therefore, when the above-described PSR is operated in such a display device, the power of the transmission unit of the system side (application processor) and the reception unit of the timing controller are turned off, thus contributing a certain portion to power consumption, but the logic unit of the timing controller , There is a disadvantage in that power consumption of the transmission unit of the timing controller and the reception unit of the data driving circuit are still ON, so there is a slight limitation in power consumption.

Against this background, an object of the present invention is to further improve power consumption reduction by PSR in electronic equipment including a display device.

Another object of the present invention is to include a remote frame buffer in a data driving circuit of the display device in a display device connected to the system side, so that when the PSR is activated, the transmission unit and data of the timing controller of the display device The object of the present invention is to significantly reduce power consumption by turning off the operation of the receiving unit of the driving circuit.

Another object of the present invention is to provide hardware for PSR operation compared to the prior art in which a large-capacity buffer must be used by including a remote frame buffer having a small capacity in each of the data driving circuits divided into two or more mounted on one display panel. It aims to be easier to implement.

In order to achieve the above object, an embodiment of the present invention provides a display panel, a data driving device mounted inside or outside the display panel to provide a data output signal to a data line formed inside the display panel, and a data driving device. And a timing controller that transmits control signals and still image data to the device, and the data driving device temporarily stores a driving data receiving unit that receives still image data from the timing controller, and the still image data received by the driving data receiving unit. The data driver extracts the still image data from the still image data storage unit, and generates a data output signal based on the still image data from the still image data storage unit when a still image is output for a certain period of time to the data line of the display panel. A display device including an output data driving control unit is provided.

In another embodiment of the present invention, as a data driving device that is mounted inside or outside the display panel and provides a data output signal to a data line formed inside the display panel, drive data receiving still image data from an external system unit or a timing controller A data driver for temporarily storing the still image data received by the receiving unit and the driving data receiving unit, and a still image data storage unit, and when a still image is output to the display panel for a certain period of time, the data driver corresponds to the still image data storage unit. A data driving circuit for a display device including a data driving control unit for extracting still image data, generating a data output signal based on the data, and outputting the data to a data line of the display panel is provided.

According to an embodiment of the present invention, by including a remote frame buffer, which is a still image data storage unit, in a data driving circuit of a display device connected to a system side including an application processor, while still image data is output In order to reduce power consumption, for example, when the Panel Self-Refresh (hereinafter referred to as'PSR') function is performed, the operation of the transmission unit of the timing controller of the display device and the driving data receiving unit of the data driving circuit are performed. By additionally deactivating, there is an effect that power consumption can be further reduced compared to a general PSR.

In addition, according to another embodiment of the present invention, a plurality of sub-data driving circuits divided into two or more in one display device each include a separate sub-remote frame buffer, so that a conventional large-capacity buffer must be used. Compared to the PSR function display device, it is effective to facilitate hardware implementation.

1 is an overall configuration diagram of an electronic device including a PSR driving display device according to a prior art to which an embodiment of the present invention can be applied.
2 is a block diagram for each function of a conventional electronic device capable of PSR operation to which an embodiment of the present invention can be applied.
FIG. 3 shows an operation flow when a PSR operation is activated and deactivated in the device of FIG. 2.
4 is an overall configuration diagram of a display device and an external system according to an embodiment of the present invention.
5 is a functional block diagram showing a detailed configuration of a display device according to an exemplary embodiment of the present invention.
6 shows whether each component operates and a data flow when an embodiment of the present invention is applied.
7 is a block diagram of a data driving circuit and a display panel of a display device according to another embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to elements of each drawing, the same elements may have the same numerals as possible even if they are indicated on different drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known configuration or function may obscure the subject matter of the present invention, a detailed description thereof may be omitted.

In addition, in describing the constituent elements of the present invention, terms such as first, second, A, B, (a), (b) may be used. These terms are only for distinguishing the component from other components, and the nature, order, order, or number of the component is not limited by the term. When a component is described as being "connected", "coupled" or "connected" to another component, the component may be directly connected or connected to that other component, but other components between each component It is to be understood that is "interposed", or that each component may be "connected", "coupled" or "connected" through other components.

1 is an overall configuration diagram of an electronic device including a PSR driving display device according to a prior art to which an embodiment of the present invention can be applied.

The entire electronic device including the conventional PSR drive capable display device to which the present invention can be applied is largely composed of an external system unit 100 and a display device 200 as shown in FIG. 1, and the external system unit is displayed such as an application processor. It refers to a system-side control unit for driving a device, and in this specification, an external system unit is used in the same sense as an “application processor (AP) unit”.

In addition, the display device 200 is again driven by an LCD, OLED method, etc., but generates a display panel 210 including a plurality of gate lines and data lines, and a gate output signal (or scan signal) of the display panel to generate a gate line. A gate driving unit 220 or a scan driving unit provided to the device, a data driving unit 230 that generates a data output signal or a source signal and provides the data to the corresponding data line, and a control signal for controlling the operation timing of the gate driving circuit and the data driving unit And a timing controller 240 that generates (gate control signals and data control signals) and provides them to the gate driver and the data driver.

At this time, the timing controller 240 is also expressed as a T-con, and in addition to the unique function of supplying a control signal to each of the above-described driving units, the timing controller 240 additionally includes a function for PSR. The detailed configuration of the 240 will be described in more detail below with reference to FIG. 2.

Meanwhile, the display panel 210 of FIG. 1 may be a liquid crystal display panel, but is not limited thereto, and an organic light emitting diode display device (OLED), a plasma display panel (PDP), etc. Other types of display panels may be used.

2 is a block diagram for each function of an electronic device capable of a conventional PSR operation to which an embodiment of the present invention can be applied.

As shown in FIG. 2, first, a display device 200 including a timing controller 240 and a display panel 210, and an AP unit for controlling the display device and providing an image related signal to the display device or It includes an external system unit 100.

The external system unit 100 may be expressed as an AP (Application Processor), a frame buffer (FB: 110), an FB controller 130, and an external system-side transmission unit that transmits signals or data to the display device side. (AP Tx; 120) may be included.

In addition, the timing controller 240 included in the display device 200 includes a timing controller receiving unit (T-con Rx) 242, a timing controller logic unit 244 that controls the overall operation of the timing controller, and a PSR operation. A remote frame buffer (RFB) 248 for temporarily storing still image data, and a timing controller transmitter (T-con Tx) 246 for transmitting image data or image signals to a data driver mounted on the display panel, and the like. Can be configured.

The timing controller logic unit 242 may perform a function unique to the timing controller, that is, a function of generating and providing various control signals to a driving unit, and processing an image signal.

When the image data received from the external system unit 100 for the PSR operation is still image data, the RFB 248 temporarily stores the still image data. When the PSR operation is activated, the timing controller logic unit 244 It performs a function of outputting the still image data stored according to the request to the timing controller logic unit 244. In this case, the timing controller logic unit 244 may perform a function of converting the still image data into a form that can be used by the data driver.

In addition, the still image data stored in the RFB 248 may be compressed and stored using a lossless compression method or the like, if necessary.

The timing controller transmission unit (T-con Tx) 246 transfers the image data received from the timing controller logic unit 244 to a data driving unit on the display panel side, more specifically, a source receiving unit (Source Rx) 232 included in the data driving unit. It performs the function of transmitting.

The display panel side includes a display unit 210 such as an LCD or OLED, and a source receiving unit 232 that may be a part of the data driving unit.

In fact, the data driver 230 may additionally include a data driving control unit or a D-IC logic unit that provides an image signal provided by the timing controller to a corresponding data line or source line in addition to the source receiving unit 232. For convenience, in FIG. 2, only a source receiving unit (Source Rx) 232 for receiving image data from the timing controller transmitting unit 246 is shown.

FIG. 3 shows an operation flow when a PSR operation is activated and deactivated in the device of FIG. 2.

Fig. 3(a) shows a case where the PSR is deactivated in the device as shown in Fig. 2, Fig. 3(b) shows a case where the PSR is activated, and the part indicated by the gray shade in Fig. 3 is turned on and driven In other words, it indicates an active state, and a white part without a shadow indicates that the component is in an inactive state that is not used, and an arrow indicates the flow of image data.

In the normal mode operation in which the PSR does not operate because the image provided from the external system unit 100 is not a still image as shown in FIG. 3A, the external system unit is controlled by the FB controller 120. After the image data stored in the frame buffer 110 of 100 is extracted, it is transmitted to the timing controller of the display device through an external system-side transmitter (AP Tx) 120.

When the timing controller receiver (T-con Rx) 242 receives the image data and transmits it to the timing controller logic unit 244, the timing controller logic unit 244 converts the image data and then converts the image data to the data driver of the display panel. It transmits to the included source receiving unit 232, and the data driver generates a data output signal or a source output signal based on the image data and then supplies it to a corresponding data line or source line.

Therefore, as shown in (a) of FIG. 3, in a normal mode operation in which the PSR does not operate, all components except for the RFB 248 of the timing controller must be activated and operated, thus increasing power consumption.

On the other hand, as shown in (b) of FIG. 3, when the image data provided for a certain time from the external system is a still image, the aforementioned PSR mode is activated. In the PSR mode, the corresponding still image data is stored in the remote frame buffer of the timing controller. It is stored in the (RFB) 248, and thus all components of the external system unit 100 are in an inactive state in which they do not operate.

In addition, the timing controller receiving unit (T-con Rx; 242) is also turned off and inactivated because there is no need to receive image data from an external system unit, and the timing controller logic unit 244 is stored in the RFB 248 of the timing controller. The still image data is extracted and transmitted to the source receiving unit 232 of the display device through the timing controller transmission unit (T-con Tx) 246 and supplied to the display panel.

Therefore, in the PSR mode, as shown in Fig. 3B, the RFB 248 of the timing controller, the timing controller logic unit 244, the timing controller transmitter (T-con Tx) 246, and the source receiving unit in the data driver ( Source Rx; 232), etc. are turned ON to operate.

As described above, in a conventional display device for a PSR operation, the operation states and image data flows of each component in the PSR deactivation state and the PSR activation state are summarized in Table 1 below.

System Side Display Side PSR OFF Video Source → AP Tx → T- con Rx → T- con Logic → T- con Tx → Source Rx → Panel PSR ON X → X → X → RFB → T- con Logic → T- con Tx → Source Rx → Panel

As shown in FIG. 3 and Table 1, in a general PSR capable display device, even if the PSR operation is activated to reduce power consumption, the source receiving unit included in the timing controller transmitting unit (T-con Tx) 246 and the data driving unit 230 is Since Rx; 232) must still be turned on and operated, there is a limit to power consumption reduction.

The embodiment of the present invention focuses on this point, and a data driver for temporary storage of still image data for a PSR on a data driver or a data driver circuit mounted inside or outside the display panel D-IC Remote Frame Buffer) to turn off the operation of the timing controller transmitter and the drive data receiver on the data driving circuit during the PSR operation, thereby further reducing power consumption.

The configuration of an embodiment of the present invention will be described in more detail. As a data driving device that is mounted inside or outside the display panel and provides a data output signal to a data line formed inside the display panel, the data driving device is an external system unit or a timing device. A driving data receiving unit that receives still image data from the controller, a data driving unit that temporarily stores the still image data received by the driving data receiving unit, a D-IC Remote Frame Buffer, and a panel self-refresh (PSR) operation. When this is activated, the data driving unit may include a data driving logic unit (D-IC Logic) that extracts the corresponding still image data from the remote frame buffer and generates and outputs a data output signal based thereon.

In addition, in another embodiment of the present invention, a display device including a display panel including the data driving circuit as described above, and a timing controller for transmitting data control signals and still image data to the data driving circuit can be provided. .

Hereinafter, detailed configurations of embodiments of the present invention will be described in detail with reference to FIG. 4.

4 is an overall configuration diagram of a display device and an external system according to an embodiment of the present invention.

The display device 500 according to an embodiment of the present invention is a display device that receives and displays image data from an external system.

The display device includes a data driving circuit (Drive IC) as a data driving device that provides a data output signal to the display panel 510 and a data line (DL) mounted inside or outside the display panel and formed inside the display panel in detail. It may be configured to include a D-IC; 530, and a timing controller 540 for transmitting various control signals and still image data to the data driving circuit 530.

In addition, the data driving circuit 530 includes a driving data receiving unit 532, which is a receiving unit that receives various control signals and still image data from a timing controller, and a data driving unit that temporarily stores still image data received by the driving data receiving unit. A data driver remote frame buffer 534 (D-IC Remote Frame Buffer; hereinafter referred to as'D-IC RFB') as a data storage unit may be included.

In addition, the data driving circuit 530 is used to reduce power consumption while a still image is displayed on the display panel for a certain period of time. For example, when the PSR operation is activated, the corresponding still image data is received from the D-IC FRB 534. A data driving logic unit 536 (D-IC Logic) as a data driving control unit for extracting and generating a data output signal based on the data output to the corresponding data line may be further included.

In the following specification, as a configuration for reducing power consumption when still image data is output to the display panel for a certain period of time, a means for temporarily storing still image data included in the data driving device is defined as a data driving unit and still image data storage unit. As an implementation form thereof, a data driver remote frame buffer (D-IC FRB) is illustrated.

In addition, in the following specification, a data driving circuit called a drive IC (D-IC) is described as an example of a data driving device, but is not limited thereto, and all types of output signals capable of generating and supplying an image related output signal to the display panel It may include a driving device.

In addition, as an example of the data driving control unit included in the data driving device, a data driving logic unit is represented and described, but is not limited to such terms, and transmitting and receiving a PSR control signal with the timing controller control unit, and performing a PSR operation. The concept includes any type of control unit or controller capable of extracting the corresponding still image data from the remote frame buffer of the data driver and generating a data output signal based on the data and supplying it to the data line or source line of the display panel.

In addition, a receiving unit included in the data driving apparatus and receiving all data from the outside is defined as a driving data receiving unit, but the expression is not limited thereto, and other expressions such as a source data receiving unit may be used. The driving data receiving unit is included in the data driving circuit and performs a function of receiving all signals such as a data control signal (DCS) and image source data from a timing controller.

The display panel 510 in the embodiment as shown in FIG. 4 may be a liquid crystal display panel, but is not limited thereto, and an organic light emitting diode display device (OLED), a plasma display device (PDP) Panel) and other types of display panels.

That is, the method of the display panel is not limited to a specific type as long as the data driving circuit according to the exemplary embodiment of the present invention can be used.

However, for convenience of understanding, a display panel according to an exemplary embodiment of the present invention will be described below by representing a liquid crystal display panel.

The liquid crystal panel, which is the display panel 510, includes an array substrate as a lower substrate on which a plurality of gate lines GL or scan lines, data lines DL or source lines, and a plurality of thin film transistors are formed, a color filter and a black matrix (BM). ) And the like, as an upper substrate, and a liquid crystal layer injected therebetween.

In the display panel 510, a plurality of pixels P defined as an intersection area between the gate line GL and the data line DL are formed. That is, data lines and gate lines cross the lower array substrate, and pixels composed of m × n (m,n are positive integers) liquid crystal cells (Clc) or pixels are formed in a matrix form by the cross structure. do.

Each of the pixels includes a thin film transistor (TFT), a pixel electrode connected to the TFT, a storage capacitor, and the like. The pixel is driven by a voltage difference between the pixel electrode charging the data voltage through the TFT and the common electrode to which the common voltage Vcom is applied to adjust the transmission amount of incident light to implement a display image corresponding to the image data.

Meanwhile, a black matrix, a color filter, and a common electrode are formed on the upper glass substrate of the display panel 510. The common electrode is formed on the upper glass substrate in a vertical electric field driving method such as the TN mode and the VA mode, and may be formed on the lower glass substrate together with the pixel electrode in a horizontal electric field driving method such as the IPS mode and the FFS mode.

Meanwhile, as a circuit or driver for driving the display panel 510, a gate driving circuit 520 for driving a gate line, a data driving circuit 530 for driving a data line, and a timing controller 540 are included. can do.

In this specification, the display panel 510, the gate driving circuit 520, and the data driving circuit 530 are described as having separate configurations. However, in some cases, at least one of the driving circuits may include various driving elements It may follow a chip-on-glass (COG) method formed directly on the device, and in this case, the display panel 510 should be interpreted as a concept including some or all of the driving circuits.

For example, among the above-described configurations, the gate driving circuit 520 for providing the gate output signal Vout to the gate line is a TFT array according to the Gate-In-Panel (hereinafter referred to as'GIP') method. It may be formed directly on the lower substrate of the display panel through a process. That is, the gate driving circuit may be formed in the non-display area NAA outside the display area AA of the display panel 510 and may be symmetrically formed on both left and right (or upper and lower) sides of the panel, but is limited thereto. It is not.

In addition, the timing controller 540 controls the data driving circuit 530 based on the functions of a basic timing controller, that is, a vertical/horizontal synchronization signal input from a host system or an external system, and external timing signals such as image data and clock signals. A function of generating and outputting a data control signal (DCS) for controlling the gate driving circuit 520 and a gate control signal (GCS) for controlling the gate driving circuit 520, and an image input from the external system 400 A function of converting data into a data signal format used by the data driving circuit 530 and supplying the converted image data to the data driving circuit 530 may be performed.

In addition, the timing controller 540 has additional configurations and functions according to an embodiment of the present invention, which will be described in more detail below with reference to FIG. 5.

The data driving circuit 530 of FIG. 4 is a function of a basic data driver, that is, in response to the data control signal DCS input from the timing controller 540 and the converted image data, the image data is a voltage value corresponding to the gray scale value. It converts into a data signal (analog pixel signal or data voltage) and supplies it to the data line DL.

The gate driver 520 sequentially supplies a scan signal (a gate pulse or a scan pulse or a gate on signal) to the gate line GL in response to the gate control signal GCS input from the timing controller 540.

5 is a functional block diagram showing a detailed configuration of a display device 500 according to an exemplary embodiment of the present invention.

As shown in FIG. 5, the display device 500 according to an embodiment of the present invention is a device that receives image data from an external system 400 and displays an image, and includes a timing controller 540 side and a panel side display panel. It may be configured to include 510 and a data driving circuit 530.

The external system unit 400 may be expressed as an application processor (AP), and again, a frame buffer (FB: 410) for temporarily storing various image data in a memory, and an FB controller that controls the frame buffer ( 440, and an external system-side transmitter (AP Tx) 420 that transmits image data to the display device.

In addition, the timing controller 540 included in the display device 500 according to an embodiment of the present invention is again a timing controller receiving unit (T-) for receiving image data or an image signal from an external system-side transmitting unit (AP Tx) 420. con Rx; 542, a timing controller logic unit (T-con Logic) 544 for controlling the overall operation of the timing controller, and a data driving circuit 530 mounted on a display panel for image data or image signals. It may be configured to include a timing controller transmission unit (T-con Tx) 546 for transmission to the driving data receiving unit 532 included in the data driving circuit.

In addition, when the timing controller 540 supports the PSR operation according to the conventional configuration, the timing controller 540 may include a timing controller remote frame buffer (T-con RFB) for temporarily storing still image data transmitted from an external system; 548) may be further included.

The data driving circuit 530 included in the display device 500 according to an embodiment of the present invention includes a driving data receiving unit 532 for receiving image data from the timing controller 540 and a driving data receiving unit. A data driver that temporarily stores received still image data may include a data driver remote frame buffer 536 (D-IC Remote Frame Buffer; hereinafter referred to as'D-IC RFB') as a still image data storage unit. .

In addition, when the panel self-refresh (PSR) operation of the method according to the embodiment of the present invention is activated, the corresponding still image data is extracted from the D-IC RFB 536, and a data output signal is generated and output therefrom. A data driving logic unit (D-IC Logic) for controlling all operations provided to the data line may be additionally included.

According to the embodiment as shown in FIG. 5, by including the D-IC RFB 536, which is a separate frame buffer, inside the data driving circuit 530, the source part in the eDP standard becomes the timing controller 540, and the remote for PSR It may be understood that the sink unit including the frame buffer becomes the data driving circuit 530.

That is, in the existing PSR, the external system is the source part of the eDP standard and the timing controller of the display device including the RFB becomes the sink part. In the embodiment of the present invention, the data driving circuit 530 is a new method for PSR. It is possible to provide a PSR, whereby, as will be described further with reference to FIG. 6 below, there is an effect of further reducing the power consumption of the device.

6 shows whether each component operates and a data flow when an embodiment of the present invention is applied.

FIG. 6(a) is a view provided to contrast with the embodiment of the present invention, and shows a case in which PSR in the same manner as in FIG. 3 is performed, and FIG. 6(b) shows an embodiment of the present invention. It is applied, but the external system 400 and the timing controller 540 is a case that supports the existing PSR standard, Figure 6 (c) is applied to the embodiment of the present invention, the external system 400 and the timing controller 540 A case where the existing PSR standard is not supported is shown.

Similar to FIG. 3, in FIG. 6, the components indicated by gray shades represent the ON and driven state (active state), and the white part without the shade is OFF to indicate that the component is in an inactive state that is not in use. Indicates the flow of image data.

As shown in (a) of FIG. 6, when the new PSR according to the embodiment of the present invention is not applied, that is, in the PSR operation mode according to the conventional method, the timing controller logic unit T- Con Logic) extracts the still image data from the RFB and transmits it to the display panel, so the timing controller transmitter (T-con Tx) and the source receiver (Source Rx) of the data driving circuit are still ON and operated, thus reducing power consumption. There are limits to

On the other hand, as shown in (b) of FIG. 6, when the PSR of the method according to the embodiment of the present invention is applied, but the external system and the timing controller support the PSR mode operation according to the conventional method as shown in FIG. When the image continues for a certain period of time, since still image data is temporarily stored in the D-IC RFB in advance, it is sufficient for the data driving circuit to drive the data line based on the still image data.

Therefore, as shown in (b) of FIG. 6, in the device according to the embodiment of the present invention, when the PSR is operated, only the D-IC RFB is activated on the display panel side, and the timing controller transmitter (T-con Tx) and the data driving circuit are Since the driving data receiving unit 532 is deactivated, power consumption can be further reduced.

At this time, the timing controller logic unit (T-con logic) must always be in the ON state because it must perform the gate control signal generation/output operation regardless of the PSR mode.

6(c) shows a case in which the embodiment of the present invention as shown in FIG. 5 is applied, but the external system and the timing controller do not support the PSR according to the conventional method. In this case, the PSR mode according to the embodiment of the present invention operates. Even so, the external system, the timing controller receiver (T-con Rx), and the timing controller logic unit (T-con Logic) must be turned ON to operate. However, even in this case, since still image data need only be provided directly from the D-IC RFB inside the display panel, the operation of the timing controller transmission unit (T-con Tx) and the driving data receiving unit 532 of the data driving circuit are turned off. It is possible to reduce power consumption to some extent.

Table 2 below summarizes whether components are activated (ON/OFF) and image data flow in the case of FIGS. 6A to 6C.

System Side Display Side PSR OFF Memory → AP Tx → T- con Rx → T- con Logic → T- con Tx → Drive data Rx → Panel Of the present invention PSR ON
( AP , T- con Support this PSR) OFF → OFF → OFF → T- con Logic → OFF → OFF → Panel Of the present invention PSR ON
( AP , T- con This PSR is not supported) Memory → AP Tx → T- con Rx → T- con Logic → OFF → OFF → Panel

7 is a block diagram of a data driving circuit and a display panel of a display device according to another embodiment of the present invention.

In the display device according to the exemplary embodiment of FIG. 7, configurations of an external system and a timing controller are the same as those of FIGS. 4 to 6, but differ only in the data driving circuit.

In the embodiment illustrated in FIG. 7, the data driving circuit 700 includes n (n=N/k, a natural number of n≥2) connected to k data lines out of the N data lines formed on the display panel. Including driving circuits 710, 720, 730, each sub data driving circuit 710, 720, 730 is a sub driving data receiving unit 712, 722, 732 that receives still image data from an external system unit or a timing controller Wow, Sub D-IC Remote Frame Buffer (Sub D-IC Remote Frame Buffer; 716, 726, 736) that temporarily stores the still image data received by the sub drive data receiver, and the panel self-refresh (PSR) operation is activated. If so, it may include sub data driving logic units 714, 724, and 726 that extract corresponding still image data from the sub data driver remote frame buffer and generate and output a data output signal based thereon.

That is, in the embodiments of Figs. 4 to 6, the data driving circuit is implemented as a single circuit to control all N data lines at once, whereas in the embodiment of Fig. 7 the data driving circuit drives a plurality (n) of sub-data. It is implemented by dividing into circuits, but each sub-data driving circuit has a structure including a sub-D-IC RFB separately.

In FIG. 7, there are a total of N data lines, and each of the sub data driving circuits 710, 720, and 730 is connected to each of k data lines to drive the data lines. As a result, the total number of sub data driving circuits An example in which n is M/k is shown, but is not limited to this configuration.

According to the embodiment of FIG. 7, when the PSR operation according to the present invention is performed, the timing controller transmission unit (not shown; T-con Tx) as well as the sub driving data receiving units 712, 722, and 732 of each sub data driving circuit The power consumption can be reduced because the operation of the device can be turned off.

In addition, when compared with the embodiments of FIGS. 4 to 6, when the embodiment of FIG. 7 is used, the capacity of the sub data driver remote frame buffer (Sub D-IC RFB) is a single data driver remote according to FIGS. 4 to 6 It only needs to have a size of 1/n compared to the capacity of the frame buffer (D-IC RFB).

In fact, there has been a hardware limitation in that the capacity of the RFB must be considerably large because a fairly large capacity of still image data must be buffered for the PSR operation. In order to overcome or avoid the capacity limitation of the RFB, various methods of compressing still image data or deactivating the PSR operation when the capacity of the still image data to be buffered is large have been proposed.

According to the embodiment of FIG. 7, since the capacity of the sub D-IC RFBs 716, 726, and 736 included in the sub data driving circuit can be relatively small, various problems due to the aforementioned buffer capacity limit can be solved. It works.

That is, according to the embodiment of FIG. 7, each of a plurality of sub-data driving circuits divided into two or more arranged in one display device separately includes a sub-remote frame buffer having a small capacity, so that a large-capacity buffer must be used. Compared to the conventional PSR function display device, there is an effect of facilitating hardware implementation.

8 shows a control signal signaling process between a timing controller (source unit) and a data driving circuit for a PSR operation according to an embodiment of the present invention.

That is, FIG. 8 is a preliminary check process performed between a timing controller that is a source unit of the eDP standard and a data driver circuit that is a sink unit of the eDP standard for the PSR mode operation according to an embodiment of the present invention. More specifically, it may be a control signal signaling process for a PSR performed between a timing controller control unit included in the timing controller and a data driving control unit included in the data driving device D-IC.

First, the timing controller reads the "sink PSR Capability DPCD (Display Port Configuration Data) register" included in the data driving circuit to determine whether PSR is possible (Step A).

In the "sink PSR Capability DPCD register", information indicating whether the data driving circuit serving as the sink unit can perform the PSR operation according to the present invention is recorded. The data driving circuit returns "sink PSR Capability" information to the timing controller in response to the request from the timing controller (Step B).

Next, the timing controller checks the "sink PSR Capability" information and updates the "sink PSR configuration DPCD register" included in the data driving circuit to "Source transmitter state in PSR active", "CRC verification in PSR active" and Set the same state as "Frame capture indication" (Step C).

When the update is made, the data driving circuit, which is the sink unit, transmits an "ACK" signal to the timing controller. (Step D) Then, the data driving circuit performs the PSR function recorded in the "sink PSR configuration DPCD register" at the request of the timing controller. After activation, the "ACK" signal is sent to the timing controller (steps E, F).

Next, the timing controller as the source unit transmits the still image data to the driving data receiving unit of the data driving circuit so that it can be stored in the data driving unit remote frame buffer (D-IC RFB). (Step G)

Using the embodiment of the present invention as described above, a data driver for temporary storage of still image data for a PSR on a data driver or data driver circuit mounted inside or outside the display panel D-IC Remote Frame Buffer ), there is an effect that additional power consumption can be reduced by turning off the operation of the timing controller transmitter and the driving data receiver on the data driving circuit during the PSR operation.

That is, in the conventional PSR operation mode in which the remote frame buffer is provided inside the timing controller, the timing controller logic unit (T-con Logic) must extract the still image data from the RFB and transmit it to the display panel in the process of performing the PSR. , The timing controller transmission unit (T-con Tx) and the source receiving unit (Source Rx) of the data driving circuit are still ON and operated, so there is a limit to power consumption reduction, but according to an embodiment of the present invention, when the PSR is operated, it is displayed On the panel side, only the D-IC RFB is activated, and power consumption can be further reduced by deactivating the timing controller transmitter (T-con Tx) and the receiver of the data driving circuit.

In addition, according to another embodiment of the present invention, each of a plurality of sub-data driving circuits divided into two or more arranged in one display device separately includes a sub-remote frame buffer having a small capacity, so that a large-capacity buffer must be used. Compared to the conventional PSR function display device, it also has the effect of facilitating hardware implementation.

The description above and the accompanying drawings are merely illustrative of the technical idea of the present invention, and those of ordinary skill in the technical field to which the present invention pertains, combinations of configurations without departing from the essential characteristics of the present invention Various modifications and variations, such as separation, substitution, and alteration, will be possible. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain the technical idea, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

400: external system (AP) 500: display device
510: display panel 520: gate driving circuit
530: data driving circuit (D-IC) 532: driving data receiving unit
534: data driving logic unit (D-IC logic)
536: Data driver remote frame buffer (D-IC RFB)
540: timing controller (T-con)
542: Timing controller receiver (T-con Rx)
544: timing controller logic unit (T-con Logic)
546: Timing controller transmitter (T-con Tx)
548: Timing controller remote frame buffer (T-con RFB)
710, 720, 730: sub data driving circuit
712, 722, 732: sub drive data receiver
714, 724, 734: sub data driving logic unit (D-IC logic)
716, 726, 736: sub data driver remote frame buffer (D-IC RFB)

Claims (14)

As a display device that receives and displays image data from an external system,
Display panel;
A data driving device mounted inside or outside the display panel to provide a data output signal to a data line formed inside the display panel;
A timing controller receiving unit (T-con Rx) for transmitting control signals and still image data to the data driving device and receiving image data from the external system, a timing controller logic unit, and the image data of the data driving device. Includes; a timing controller including a timing controller transmission unit for transmitting to the drive data receiving unit,
The data driving device includes a driving data receiving unit for receiving still image data from the timing controller, a data driving unit for temporarily storing still image data received by the driving data receiving unit, a still image data storage unit, and a still image for a predetermined time. In the case of output, a data driving control unit for extracting the corresponding still image data from the still image data storage unit of the data driving unit, generating a data output signal based thereon, and outputting a data output signal to the data line of the display panel,
The display device, wherein the timing controller transmitting unit and the driving data receiving unit of the data driving device are turned off while a panel self-refresh in which a still image is output is performed to reduce power consumption. The method of claim 1,
The data driving unit still image data storage unit is a data driving unit remote frame buffer (D-IC RFB) as a storage device included in the data driving circuit, and the data driving unit remote frame buffer is a still image for a predetermined time. And outputting the still image data stored while the output panel self-refresh is performed. delete The method of claim 1,
The timing controller further comprises a timing controller remote frame buffer (T-con RFB) for temporarily storing still image data among image data received from an external system. The method of claim 2,
And while the panel self-refresh is being performed, the data driving control unit extracts the corresponding still image data from the remote frame buffer of the data driving unit and generates and outputs a data output signal based thereon. The method of claim 1,
The data driving device includes n sub-data driving circuits (n=N/k, a natural number of n≥2) each connected to k data lines among the N data lines formed on the display panel,
The sub data driving circuit includes a sub driving data receiving unit receiving still image data from the external system or a timing controller, and a sub data driving unit remote frame buffer (Sub D) temporarily storing still image data received by the sub driving data receiving unit. -IC Remote Frame Buffer) and during the panel self-refresh (PSR) operation, extracts the corresponding still image data from the remote frame buffer of the sub data driver, generates a data output signal based on it, and outputs it to the corresponding data line. And a sub-data driving logic unit (D-IC Logic). The method of claim 6,
Wherein the sub data driver remote frame buffer (Sub D-IC RFB) has a size of 1/n of the capacity of a single data driver remote frame buffer (D-IC RFB). The method of claim 2,
The data driving control unit transmits and receives a PSR control signal between the timing controller logic unit and extracts the corresponding still image data from the remote frame buffer of the data driving unit while the PSR operation is being performed, and generates a data output signal based thereon. A display device, characterized in that. A data driving device that is mounted inside or outside a display panel and provides a data output signal to a data line formed inside the display panel,
A driving data receiving unit for receiving still image data from an external system or a timing controller;
A data driving unit still image data storage unit for temporarily storing still image data received by the driving data receiving unit;
When a still image is output on the display panel for a certain period of time, the data driving unit extracts the corresponding still image data from the still image data storage unit, generates a data output signal based on it, and outputs the data to the data line of the display panel. It includes a control unit,
The timing controller transmits a control signal and still image data to the data driving device, and transmits a timing controller receiver (T-con Rx) for receiving image data from the external system, a timing controller logic unit, and the image data. And a timing controller transmitting unit for transmitting to the driving data receiving unit of the data driving device,
A data driving device for a display device, characterized in that power consumption is reduced by turning off the timing controller transmitting unit and the driving data receiving unit of the data driving device while a panel self-refresh in which a still image is output is being performed. . The method of claim 9,
The data driving unit still image data storage unit is a data driving unit remote frame buffer (D-IC RFB) as a storage device included in the data driving circuit, and the data driving unit remote frame buffer is a still image for a predetermined time. The data driving apparatus for a display device, characterized in that to output the still image data stored while the output panel self-refresh is performed. The method of claim 10,
While the panel self-refresh operation is being performed, the data driving control unit extracts the corresponding still image data from the remote frame buffer of the data driving unit, and generates and outputs a data output signal based thereon. Device. The method of claim 10,
The data driving device includes n sub-data driving circuits (n=N/k, a natural number of n≥2) each connected to k data lines among the N data lines formed on the display panel,
The sub data driving circuit includes a sub driving data receiving unit receiving still image data from the external system or a timing controller, and a sub data driving unit remote frame buffer (Sub D) temporarily storing still image data received by the sub driving data receiving unit. -IC Remote Frame Buffer) and sub data driving logic that extracts the corresponding still image data from the remote frame buffer of the sub data driver while the panel self-refresh (PSR) operation is being performed, and generates and outputs a data output signal based thereon A data driving device for a display device, comprising: a unit (D-IC Logic). The method of claim 12,
The data driving apparatus for a display device, wherein the sub data driving unit remote frame buffer (Sub D-IC RFB) has a size of 1/n of a capacity of a single data driving unit remote frame buffer (D-IC RFB). The method of claim 10,
The data driving control unit transmits and receives a PSR control signal between the timing controller logic unit and extracts the corresponding still image data from the remote frame buffer of the data driving unit while the PSR operation is being performed, and generates a data output signal based thereon. A data driving device for a display device, characterized in that.

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