Display device

Abstract

The present invention provides a display device comprising a data driver that generates sampling voltage and temperature data, and a timing control unit that supplies a bias control signal and image data to the data driver and varies the bias control signal based on the sampling voltage and temperature data.

Description

Technology Field

[0001] The present invention relates to a display device. Background Technology

[0002] As the information society develops, the demand for display devices to display images is increasing in various forms. Accordingly, various display devices such as Liquid Crystal Displays (LCDs), Plasma Display Panels (PDPs), and Organic Light Emitting Displays (OLEDs) are being utilized in recent years.

[0003] Among display devices, organic light-emitting diodes (OLEDs) are self-emissive and offer superior viewing angles and contrast ratios compared to liquid crystal displays (LCDs). Furthermore, they do not require a separate backlight, enabling lightweight and thin designs, and offer the advantage of lower power consumption. Additionally, OLEDs can be driven at low DC voltages, feature fast response speeds, and, notably, have the advantage of low manufacturing costs.

[0004] The display device includes a display panel that displays an image and a data driver that supplies data voltage to the display panel. At this time, the load of the display panel may vary depending on the physical conditions of the display panel. For example, the load of the display panel may vary depending on the size of the display panel.

[0005] As the load on the display panel changes, the slew rate of the data driver may change. Specifically, when the data driver supplies data voltage to the display panel, the speed at which the display panel responds to the data voltage and outputs an image may be delayed. Alternatively, the data voltage input to the display panel may be smaller than the voltage required to drive the display panel. Consequently, the display panel may not operate stably, and the quality of the display panel may deteriorate.

[0006] Alternatively, even if data voltage is stably supplied to the display panel, the temperature of the data driver may not satisfy constant conditions. In this case, the data driver may not operate stably. Furthermore, if the display device is an organic light-emitting display, the organic light-emitting diodes constituting the organic light-emitting display are susceptible to degradation, so the display panel may not operate stably.

[0007] To improve this, there is the inconvenience of having to directly measure the magnitude of the data voltage suitable for the load of the display panel and the temperature of the data driver to directly verify the conditions of the data voltage and the temperature of the data driver. The problem to be solved

[0008] The present invention aims to provide a display device capable of automatically setting the output voltage and temperature of a data driving unit, and a method for driving the same. means of solving the problem

[0009] The present invention provides a display device comprising a display panel including a plurality of pixels, a data driving unit that supplies a data voltage to the display panel and generates a sampling voltage and temperature data, a timing control unit that supplies a bias control signal and image data to the data driving unit and varies the bias control signal based on the sampling voltage and temperature data, wherein the data driving unit comprises an output amplifier unit that generates an amplifier voltage based on the bias control signal and image data, a sampling unit that samples the amplifier voltage at a preset period and outputs a sampling voltage, and a temperature sensor that measures the temperature of the data driving unit and generates temperature data.

[0010] In addition, the present invention provides a driving method for a display device comprising the steps of: a data driver generating an amplifier voltage and sampling the amplifier voltage based on a bias voltage and an analog data signal; a temperature of the data driver and / or the surroundings of the data driver at a preset period to generate temperature data; a step of determining whether the amplifier voltage has reached a target voltage at the time of sampling the amplifier voltage; a step of determining whether the temperature data has reached a target temperature; and a step of resetting a bias control signal that controls the magnitude of the bias voltage according to the determination result of the amplifier voltage and the target voltage and the determination result of the temperature data and the target temperature. Effects of the invention

[0011] According to the present invention, by automatically setting the optimal value of the output voltage of the data driving unit and the optimal value of the temperature of the data driving unit, the data driving unit is stably driven and the quality of the display panel is improved. Brief explanation of the drawing

[0012] FIG. 1 is a block diagram of a display device according to one embodiment of the present invention. Figure 2 is a circuit diagram of the pixel of Figure 1. FIG. 3 is a block diagram of a data driving unit and a timing control unit according to an embodiment of the present invention. FIG. 4 is a block diagram of a data drive IC according to one embodiment of the present invention. FIG. 5 is a circuit diagram of an output amplifier section according to one embodiment of the present invention. FIG. 6 is a flowchart showing a method of driving a display device according to one embodiment of the present invention. FIGS. 7 to 10 are graphs of amplifier voltage and temperature data according to one embodiment of the present invention. Specific details for implementing the invention

[0013] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0014] The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining embodiments of the present invention are exemplary, and therefore the present invention is not limited to the depicted details. Throughout the specification, the same reference numerals refer to the same components.

[0015] Furthermore, in describing the present invention, if it is determined that a detailed description of related known technology may unnecessarily obscure the essence of the present invention, such detailed description is omitted.

[0016] Where terms such as 'includes,' 'have,' and 'consists of' are used in this specification, other parts may be added unless 'only' is used. Where a component is expressed in the singular, it includes cases where it is in the plural unless specifically stated otherwise. In interpreting a component, it is interpreted to include an error range even without separate explicit description.

[0017] In the case of describing a positional relationship, for example, when the positional relationship between two parts is described using expressions such as 'on,' 'upper,' 'lower,' or 'next to,' one or more other parts may be located between the two parts unless 'immediately' or 'directly' is used.

[0018] In the case of an explanation of a temporal relationship, for example, when a temporal sequence is explained using 'after', 'following', 'next', 'before', etc., it may include cases where the sequence is not continuous unless 'immediately' or 'directly' is used.

[0019] The features of each of the various embodiments of the present invention may be combined or combined with one another, either partially or wholly, and may technically enable various interlocking and operation. Each embodiment may be implemented independently of one another or may be implemented together in an associated relationship.

[0020] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0021] FIG. 1 is a block diagram of a display device (1000) according to one embodiment of the present invention.

[0022] Referring to FIG. 1, the display device (1000) may include a display panel (100), a gate driving unit (200), a data driving unit (300), and a timing control unit (400).

[0023] Hereinafter, the display device according to the present invention will be described assuming that it is an organic light-emitting display device. However, it is not limited thereto, and the display device according to the present invention may be a display device other than an organic light-emitting display device.

[0024] The display panel (100) may include a display area for displaying images and a non-display area provided on the outer edge of the display area. The non-display area may be provided to surround the display area, but is not limited thereto.

[0025] The display area may be provided with a plurality of gate lines (GL1 to GLm, where m is a natural number greater than 1) and a plurality of data lines (DL1 to DLn, where n is a natural number greater than 1). The plurality of gate lines (GL) and the plurality of data lines (DL) may intersect.

[0026] Multiple pixels (P) may be provided in an area where multiple gate lines (GL) and multiple data lines (DL) intersect. That is, the multiple pixels (P) may be arranged in a matrix form consisting of multiple rows and columns. Additionally, each of the multiple pixels (P) may receive a scan signal through the multiple gate lines (GL) and receive a data signal through the multiple data lines (DL).

[0027] The gate driver (200) can receive a gate driver control signal (GCS) from the timing control unit (400). The gate driver (200) can supply a scan signal to the gate line (GL) according to the gate driver control signal (GCS).

[0028] Additionally, the gate driver (200) may be provided in a non-display area on one or both sides of the display area of ​​the display panel (100) in a GIP (gate driver in panel) manner, but is not limited thereto.

[0029] The data driver (300) can receive a data driver control signal (DCS) and image data (IDATA) from the timing control unit (200). The data driver (300) can convert the image data (IDATA) into a data voltage according to the data driver control signal (DCS). Additionally, the data driver (300) can supply the converted data voltage to the data line (DL).

[0030] The timing controller (200) can control the operation timing of the gate driver (200) and the data driver (300). The timing controller (200) can generate a gate driver control signal (GCS), a data driver control signal (DCS), and image data (IDATA) according to the timing signal supplied from the host system.

[0031] The timing controller (200) can supply a gate driver control signal (GCS) to the gate driver (200) and supply a data driver control signal (DCS) and image data (IDATA) to the data driver (300).

[0032] The timing controller (200) can receive sensing data (SEN) from the data driver (300). The sensing data (SEN) can be generated using temperature data and voltage data from the data driver (300). The timing controller (200) can set the data driver control signal (DCS) and image data (IDATA) to be supplied to the data driver (300) through the sensing data (SEN). A detailed description of the temperature data and voltage data of the data driver (300) will be provided later.

[0034] Figure 2 is a diagram showing an example of a circuit diagram of a pixel (P) of Figure 1.

[0035] As described above, the display panel (100) may include a plurality of pixels (P). The plurality of pixels (P) may be arranged in a matrix form consisting of a plurality of rows and columns. FIG. 2 illustrates a circuit diagram of one of the pixels (P).

[0036] Referring to FIG. 2, a pixel (P) may include a pixel driver (PD) and a light-emitting element (ED). The pixel driver (PD) may be a circuit for driving the light-emitting element (ED). Additionally, the pixel driver (PD) may include a driving transistor (DT), a switching transistor (ST), and a capacitor (C).

[0037] A driving transistor (DT) may be provided between a high potential voltage line (VDDL) and a light-emitting element (ED). The driving transistor (DT) can control the driving current. Specifically, the driving transistor (DT) can control the current flowing from the high potential voltage line (VDDL) to the light-emitting element (ED) according to the voltage difference between the gate electrode and the source electrode.

[0038] The gate electrode of the driving transistor (DT) is connected to the first electrode of the switching transistor (ST), the first electrode (source electrode or drain electrode) is connected to the anode electrode of the light-emitting element (ED), and the second electrode (drain electrode or source electrode) can be connected to a high potential voltage line (VDDL) to which a high potential voltage (VDD) is supplied.

[0039] The switching transistor (ST) can be driven by the scan signal (SC) of the gate line (GL). When the switching transistor (ST) is turned on by the scan signal (SC), the switching transistor (ST) can supply the data voltage (V_data) of the data line (DL) to the gate electrode of the driving transistor (DT).

[0040] Additionally, the gate electrode of the switching transistor (ST) can be connected to the gate line (GL), the first electrode can be connected to the gate electrode of the driving transistor (DT), and the second electrode can be connected to the data line (DL).

[0041] A capacitor (C) may be provided between the gate electrode and the source electrode of a driving transistor (DT). The capacitor (C) can store the voltage difference between the gate voltage and the source voltage of the driving transistor (DT).

[0042] FIG. 2 illustrates that the driving transistor (DT) and the switching transistor (ST) are formed as N-type MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), but is not limited thereto. For example, the driving transistor (DT) and the switching transistor (ST) may be P-type MOSFETs.

[0043] Additionally, the first electrode may be a source electrode and the second electrode may be a drain electrode, but is not limited thereto. For example, the first electrode may be a drain electrode and the second electrode may be a source electrode.

[0044] The light-emitting element (ED) can emit light depending on the current supplied through the driving transistor (DT). The anode electrode of the light-emitting element (ED) is connected to the source electrode of the driving transistor (DT), and the cathode electrode of the light-emitting element (ED) can be connected to a low potential voltage line (VSSL) to which a low potential voltage (VSS) is supplied. The low potential voltage (VSS) can be a voltage lower than the high potential voltage (ELVDD).

[0045] When the light-emitting element (ED) is an organic light-emitting diode (OLED), the light-emitting element (ED) may include an anode electrode, a hole transporting layer, an emitting layer, an electron transporting layer, and a cathode electrode. When voltage is applied to the anode electrode and the cathode electrode by a pixel driver (PD), holes and electrons move to the emitting layer through the hole transporting layer and the electron transporting layer, respectively, and holes and electrons can combine with each other in the emitting layer. Accordingly, the light-emitting element (ED) can emit light.

[0047] FIG. 3 is a block diagram of a data driving unit (300) and a timing control unit (400) according to an embodiment of the present invention.

[0048] Referring to FIG. 3, the data driving unit (300) may include at least one data drive IC (310).

[0049] The data drive IC (310) can receive a data drive unit control signal (DCS) and image data (IDATA) from the timing control unit (400). Additionally, the data drive IC (310) can generate a data voltage (V_data) corresponding to the image data (IDATA). Additionally, the data drive IC (310) can supply the data voltage (V_data) to the display panel (100).

[0050] If the data driving unit (300) includes a single data drive IC (310), the data drive IC (310) may be identical to the data driving unit (300). In this case, multiple data lines (DL) may all be connected to a single data drive IC (310). Alternatively, if the data driving unit (300) includes multiple data drive ICs (310), the multiple data lines (DL) may be grouped, and each data line group may be connected to a corresponding data drive IC (310).

[0051] The timing control unit (400) can be connected to each data drive IC (310) via a data drive unit control signal line (DCSL). That is, the timing control unit (410) can supply a data drive unit control signal (DCS) corresponding to each data drive IC (310) via the data drive unit control signal line (DCSL).

[0052] For example, the method by which the timing control unit (400) is connected to the data drive IC (310) through the data drive unit control signal line (DCSL) may be a point-to-point method.

[0053] The timing control unit (400) can be connected to each data drive IC (310) via an image data line (IDATAL). The timing control unit (400) can supply image data (IDATA) corresponding to each data drive IC (310) via the image data line (IDATAL).

[0054] For example, the method by which the timing control unit (400) is connected to the data drive IC (310) through the image data line (IDATAL) may be a point-to-point method.

[0055] The timing control unit (400) can be connected to each data drive IC (310) via a sensing data line (SENL). That is, the timing control unit (410) can receive sensing data (SEN) corresponding to each data drive IC (310) via the sensing data line (SENL).

[0056] For example, the method by which the timing control unit (400) is connected to the data drive IC (310) via the sensing data line (SENL) may be a point-to-point method.

[0057] FIG. 4 is a block diagram of a data drive IC (310) according to one embodiment of the present invention.

[0058] As described above, the timing control unit (400) supplies a data drive unit control signal (DCS) and image data (IDATA) to the data drive IC (310), and the data drive IC (310) can supply sensing data (SEN) to the timing control unit (400).

[0059] Referring to FIG. 4, the data drive IC (310) may include a receiver (RX), a logic unit (LOGIC), a digital-to-analog converter (DAC), an output amplifier unit (OA), a sampling unit (SAM), an analog-to-digital converter (ADC), a storage unit (MEM), a temperature sensor (TEM), and a transmitter (TX).

[0060] The receiver (RX) can receive a data driver control signal (DCS) and image data (IDATA) from the timing control unit (400). The receiver (RX) can optimize the data driver control signal (DCS) and image data (IDATA) into a format that the data drive IC (310) can process.

[0061] At this time, the data driver control signal (DCS) and the optimized image data (IDATA) optimized by the receiver (RX) can be referred to as the optimization signal (S_opt). That is, the receiver (RX) receives the data driver control signal (DCS) and the image data (IDATA) as inputs and can output the optimization signal (S_opt). The receiver (RX) can supply the optimization signal (S_opt) to the logic unit (LOGIC).

[0062] The logic unit (LOGIC) may receive an optimization signal (S_opt) from the receiver unit (RX). The optimization signal (S_opt) may include a serial data signal (S_data_s), a bias control signal (S_bias), and a sampling unit control signal (S_sam). The serial data signal (S_data_s) may be optimized image data (IDATA). Additionally, the bias control signal (S_bias) may be a signal that controls the operation of the output amplifier unit (OA), and the sampling unit control signal (S_sam) may be a signal that controls the operation of the sampling unit (SAM).

[0063] The logic section (LOGIC) can supply different signals to the digital-to-analog converter (DAC), output amplifier section (OA), and sampling section (SAM), respectively.

[0064] The logic unit (LOGIC) can convert a serial data signal (S_data_s) into a parallel data signal (S_data_p). Additionally, the logic unit (LOGIC) can supply the parallel data signal (S_data_p) to a digital-to-analog converter (DAC). By converting the serial data signal (S_data_s) into a parallel data signal (S_data) by the logic unit (LOGIC), the logic unit (LOGIC) can simultaneously apply data signals to the digital-to-analog converter (DAC).

[0065] The logic unit (LOGIC) can supply a bias control signal (S_bias) to the output amplifier unit (OA). Additionally, the logic unit (LOGIC) can supply a sampling unit control signal (S_sam) to the sampling unit (SAM).

[0066] A digital-to-analog converter (DAC) can receive a parallel data signal (S_data_p) from a logic unit (LOGIC). The parallel data signal (S_data_p) may be a digital signal. Accordingly, the digital-to-analog converter (DAC) can convert the parallel data signal (S_data_p) into an analog signal.

[0067] In this case, the parallel data signal (S_data_p) converted into an analog signal can be referred to as the analog data signal (S_data_a). That is, the digital-to-analog converter (DAC) receives the parallel data signal (S_data_p) as input and can output the analog data signal (S_data_a). The digital-to-analog converter (DAC) can supply the analog data signal (S_data_a) to the output amplifier section (OA).

[0068] The output amplifier section (OA) receives a bias control signal (S_bias) from the logic section (LOGIC) and can receive an analog data signal (S_data_a) from the digital-to-analog converter (DAC). Through the bias control signal (S_bias) and the analog data signal (S_data_a), the output amplifier section (OA) can generate an amplifier voltage (V_amp). The amplifier voltage (V_amp) becomes the output voltage of the data drive IC (310), and the amplifier voltage (V_amp) can be used as the data voltage (V_data).

[0069] In addition, the output amplifier section (OA) can transmit the amplifier voltage (V_amp) to the sampling section (SAM). Meanwhile, the driving process of the output amplifier section (OA) will be described in detail in FIG. 5.

[0070] The sampling unit (SAM) receives an amplifier voltage (V_amp) from the output amplifier unit (OA) and can receive a sampling unit control signal (S_sam) from the logic unit (LOGIC). The sampling unit (SAM) can sample the amplifier voltage (V_amp) according to the sampling unit control signal (S_sam).

[0071] Specifically, when the sampling unit (SAM) is turned on by the sampling unit control signal (S_sam), the sampling unit (SAM) can measure the amplifier voltage (V_amp) at a specific point in time. In this case, the amplifier voltage (V_amp) sampled by the sampling unit (SAM) can be called the sampling voltage (V_sam). That is, the sampling unit (SAM) receives the amplifier voltage (V_amp) and the sampling unit control signal (S_sam) as inputs and can output the sampling voltage (V_sam). Additionally, the sampling unit (SAM) can supply the sampling voltage (V_sam) to an analog-to-digital converter (ADC).

[0072] An analog-to-digital converter (ADC) can convert an analog signal, the sampling voltage (V_sam), into a digital signal, the digital sampling voltage (V_sam_d). The analog-to-digital converter (ADC) can supply the digital sampling voltage (V_sam_d) to a storage unit (MEM).

[0073] The storage unit (MEM) can receive a digital sampling voltage (V_sam_d) from an analog-to-digital converter (ADC). The storage unit (MEM) can store the digital sampling voltage (V_sam_d). Specifically, while the temperature sensor (TEM) generates temperature data (T_data), the storage unit (MEM) can maintain the value of the digital sampling voltage (V_sam_d). Additionally, the storage unit (MEM) can supply the digital sampling voltage (V_sam_d) to the transmitter (TX).

[0074] The temperature sensor (TEM) can measure the temperature inside the data drive IC (310) and in an area adjacent to the data drive IC (310). The temperature sensor (TEM) can generate temperature data (T_data) using the measured temperature. Similar to the storage unit (MEM), the temperature sensor (TEM) can supply the temperature data (T_data) to the transmitter (TX). Additionally, the temperature sensor (TEM) can use various commonly used temperature sensing elements.

[0075] The transmitter (TX) can receive a digital sampling voltage (V_sam_d) from the storage unit (MEM) and temperature data (T_data) from the temperature sensor (TEM). The transmitter (TX) can convert the digital sampling voltage (V_sam_d) and the temperature data (T_data) into a format that can be processed by the timing control unit (400).

[0076] At this time, a signal including a digital sampling voltage (V_sam_d) and temperature data (T_data) converted by a transmitter (TX) can be referred to as sensing data (SEN). That is, the transmitter (TX) receives the digital sampling voltage (V_sam_d) and temperature data (T_data) as inputs and can output sensing data (SEN). The transmitter (TX) can supply the sensing data (SEN) to a timing control unit (400).

[0077] Accordingly, the timing control unit (400) supplies a data drive unit control signal (DCS) and image data (IDATA) to the data drive IC (310), and finally receives sensing data (SEN) from the data drive IC (310).

[0079] FIG. 5 is a circuit diagram of an output amplifier section (OA) according to one embodiment of the present invention.

[0080] As described above, the output amplifier section (OA) receives a bias control signal (S_bias) from the logic section (LOGIC) and can receive an analog data signal (S_data_a) from the digital-to-analog converter (DAC).

[0081] Referring to FIG. 5, the output amplifier section (OA) may include a bias circuit (BIAS), an amplifier (AMP), and an output section (OUT).

[0082] The bias circuit (BIAS) can receive a bias control signal (S_bias) from the logic unit (LOGIC). Depending on the bias control signal (S_bias), the bias circuit (BIAS) can output a bias voltage (V_bias). That is, if the value of the bias control signal (S_bias) changes, the value of the bias voltage (V_bias) can change.

[0083] The amplifier (AMP) receives an analog data signal (S_data_a) from a digital-to-analog converter (DAC) and a bias voltage (V_bias) from a bias circuit (BIAS). Depending on the analog data signal (S_data_a) and the bias voltage (V_bias), the amplifier (AMP) can generate an amplifier voltage (V_amp). Additionally, the amplifier (AMP) may be implemented as a differential amplifier or may include a differential amplifier.

[0084] Specifically, the first input terminal of the amplifier (AMP) can be connected to an analog data signal (S_data_a), and the second input terminal of the amplifier (AMP) can be connected to a bias voltage (V_bias). Additionally, the amplifier (AMP) can generate an amplifier voltage (V_amp) and output the amplifier voltage (V_amp) through the output terminal of the amplifier (AMP).

[0085] At this time, depending on the value of the bias voltage (V_bias), the magnitude of the analog data signal (S_data_a) is amplified and can be output as an amplifier voltage (V_amp). That is, the value of the bias voltage (V_bias) is determined by the bias control signal (S_bias), and the slew rate and the amplifier voltage (V_amp) can be determined by the bias voltage (V_bias).

[0086] The output section (OUT) can receive the amplifier voltage (V_amp) from the amplifier (AMP). The output section (OUT) functions as a buffer and can stabilize the amplifier voltage (V_amp). That is, the output section (OUT) can minimize the impact of the load from the display panel (100) on the amplifier (AMP). Accordingly, the amplifier voltage (V_amp) generated in the output amplifier section (OA) can be stably output through the output section (OUT). In addition, the output section (OUT) can transmit the amplifier voltage (V_amp) to the sampling section (SAM).

[0087] The output section (OUT) may include a first transistor (T1) and a second transistor (T2). The first transistor (T1) and the second transistor (T2) may be connected in series. Additionally, the gate electrode of the first transistor (T1) and the gate electrode of the second transistor (T2) may be connected to an amplifier voltage (V_amp). The gate electrode of the first transistor (T1) may be connected to the amplifier (AMP), the first electrode may be connected to a high potential voltage (VDD), and the second electrode may be connected to the second transistor (T2). Additionally, the gate electrode of the second transistor (T2) may be connected to the amplifier (AMP), the first electrode may be connected to the first transistor (T1), and the second electrode may be connected to a low potential voltage (VSS).

[0088] Figure 5 illustrates that the first transistor (T1) is a P-type MOSFET and the second transistor (T2) is an N-type MOSFET, but is not limited thereto.

[0089] In addition, in FIG. 5, the circuit of the output section (OUT) is configured using the first transistor (T1) and the second transistor (T2), but it is not limited thereto. For example, the output section (OUT) may include a buffer circuit using additional transistors in addition to the first transistor (T1) and the second transistor (T2).

[0091] FIG. 6 is a flowchart showing a method of driving a display device according to one embodiment of the present invention.

[0092] Typically, a display device can be driven on a frame basis. A single frame may include an initialization period, a sampling period, a programming period, and a light emission period. Additionally, within a single frame, the initialization period, the sampling period, the programming period, and the light emission period may proceed sequentially.

[0093] The initialization period may be a period for initializing various signals supplied to the display panel (100). Specifically, during the initialization period, the values ​​of the scan signal (SC) and data voltage (V_data) described in FIG. 2 may be initialized. Accordingly, various elements included in the pixel may also be initialized.

[0094] The sampling period may be a period for setting the values ​​of various signals supplied to the display panel (100). Specifically, the sampling period may be a period during which the driving process of the data driving unit (300) described in FIGS. 4 and FIGS. 5 takes place. That is, during the sampling period, the data driving unit (300) generates an amplifier voltage (V_amp), the timing control unit (400) receives sensing data (SEN), and finally, the data driving unit (300) can output the amplifier voltage (V_amp).

[0095] The programming period may be a period for supplying a set signal to the display panel (100). Specifically, the amplifier voltage (V_amp) set during the sampling period is supplied to the data line (DL), and the amplifier voltage (V_amp) may function as the data voltage (V_data).

[0096] The light emission period may be the period during which the display panel (100) displays an image. Specifically, the light-emitting element (ED) described in FIG. 2 may emit light during the light emission period.

[0097] Accordingly, FIG. 6 illustrates the driving method of the data driving unit (300) and the timing control unit (400) during the sampling period.

[0099] Referring to FIG. 6, in the first step (S1), a bias control signal (S_bias) can be supplied to the data driving unit (300).

[0100] Specifically, as described above in FIGS. 4 and 5, based on the data driving unit control signal (DCS) of the timing control unit (400), the data driving unit (300) can receive a bias control signal (S_bias).

[0101] The timing control unit (400) can set a bias control signal (S_bias) so that the power used in the output amplifier unit (OA) of the data driving unit (300) has a minimum value. For example, the bias control signal (S_bias) can determine the magnitude of the bias voltage (V_bias) that is output from the bias circuit (BIAS) and provided to the amplifier (AMP). For example, the bias voltage (V_bias) can be set so that the minimum value of the power used in the output amplifier unit (OA) is 1.5W, but is not limited thereto.

[0102] In the second step (S2), the data driver (300) can generate an amplifier voltage (V_amp) and sample the amplifier voltage (V_amp).

[0103] Specifically, as described above in FIGS. 4 and 5, based on a bias control signal (S_bias) and an analog data signal (S_data_a), the output amplifier section (OA) of the data driving unit (300) can generate an amplifier voltage (V_amp). In particular, since the power used in the output amplifier section (OA) is determined according to the bias control signal (S_bias), the slew rate of the amplifier (AMP) can be determined according to the bias control signal (S_bias). Additionally, since the slew rate of the amplifier (AMP) is determined according to the bias control signal (S_bias), the magnitude of the amplifier voltage (V_amp) can also be determined.

[0104] The sampling unit (SAM) can sample the generated amplifier voltage (V_amp). Specifically, when the sampling unit (SAM) is turned on by the sampling unit control signal (S_sam), the sampling unit (SAM) can measure the amplifier voltage (V_amp) at a specific point in time.

[0105] In the third step (S3), the temperature sensor (TEM) can generate temperature data (T_data). Specifically, the temperature sensor (TEM) can measure the temperature inside the data drive IC (310) and in an area adjacent to the data drive IC (310). Then, the temperature sensor (TEM) can generate temperature data (T_data) using the measured temperature.

[0106] In the fourth step (S4), it can be determined whether the amplifier voltage (V_amp) has reached the target voltage (V_target).

[0107] Specifically, the timing control unit (400) can compare the sampled amplifier voltage (V_amp) with the target voltage (V_target). The target voltage (V_target) may be a voltage value pre-set within the timing control unit (400). In particular, the target voltage (V_target) may be an optimal voltage value for stably driving the display panel (100) to which the data driving unit (300) is connected. If the digital sampling voltage (V_sam_d) does not reach the target voltage (V_target), the display panel (100) is not stably driven, and the quality of the display panel (100) may be degraded.

[0108] The target voltage (V_target) may have different values ​​depending on the physical conditions of the display panel (100). For example, the target voltage (V_target) may have different values ​​depending on the size of the display panel (100).

[0109] When the amplifier voltage (V_amp) reaches the target voltage (V_target), the 5th step (S5) can be entered.

[0110] In step 5 (S5), it can be determined whether the temperature data (T_data) has reached the target temperature (T_target).

[0111] Specifically, the timing control unit (400) can compare temperature data (T_data) with a target temperature (T_target). The target temperature (T_target) may be a temperature value pre-set within the timing control unit (400). In particular, the target temperature (T_target) may be an optimal temperature value for driving the display panel (100) to which the data driving unit (300) is connected. If the temperature data (T_data) does not reach the target temperature (T_target), the display panel (100) is not driven stably, and the quality of the display panel (100) may be degraded.

[0112] The target temperature (T_target) may have different values ​​depending on the physical conditions of the display panel (100). For example, the target temperature (T_target) may have different values ​​depending on the size of the display panel (100) or the electrical components constituting the display panel (100).

[0113] Alternatively, the target temperature (T_target) may have different values ​​depending on the physical conditions of the data driving unit (300). For example, the target temperature (T_target) may have different values ​​depending on the guaranteed temperature of the data drive IC (310) of the data driving unit (300).

[0114] When the temperature data (T_data) reaches the target temperature (T_target), the timing control unit (400) can supply the current data driver control signal (DCS) to the data driver (300). That is, the data driver (300) can receive the current bias control signal (S_bias). Accordingly, the data driver (300) can maintain the current amplifier voltage (V_amp) and the current temperature data (T_data).

[0115] On the other hand, if the amplifier voltage (V_amp) does not reach the target voltage (V_target) in the fourth step (S4), entry into the sixth step (S6) may be performed. Alternatively, even if the amplifier voltage (V_amp) reaches the target voltage (V_target) in the fourth step (S4), entry into the sixth step (S6) may be performed if the temperature data (T_data) does not reach the target temperature (T_target) in the fifth step (S5).

[0116] In step 6 (S6), the timing control unit (400) can reset the data driver control signal (DCS). Since the data driver control signal (DCS) is reset, the bias control signal (S_bias) generated based on the data driver control signal (DCS) can also be reset.

[0117] Specifically, the bias control signal (S_bias) can be reset so that the bias voltage (V_bias) increases. For example, the timing control unit (400) can reset the bias control signal (S_bias) so that the output of the output amplifier unit (OA) increases in steps. Accordingly, the magnitude of the amplifier voltage (V_amp) can also increase in steps. For example, the timing control unit (400) can reset the bias control signal (S_bias) so that the output of the output amplifier unit (OA) increases by 0.03W compared to the existing output value, but is not limited thereto.

[0118] When the 6th step (S6) is finished, the 1st step (S1) can be entered again. That is, a reset bias control signal (S_bias) can be supplied to the data driving unit (300).

[0119] In the second step (S2), the data driver (300) is driven according to the reset bias control signal (S_bias), and the output amplifier (OA) can generate a new amplifier voltage (V_amp). Additionally, in the third step (S3), the temperature sensor (TEM) can also generate new temperature data (T_data) according to the new amplifier voltage (V_amp).

[0120] When the new amplifier voltage (V_amp) reaches the target voltage (V_target) and the new temperature data (T_data) reaches the target temperature (T_target), the timing control unit (400) can supply the current data driver control signal (DCS) to the data driver (300). That is, the data driver (300) can receive the current bias control signal (S_bias). Accordingly, the data driver (300) can maintain the current amplifier voltage (V_amp) and the current temperature data (T_data).

[0121] On the other hand, if the new amplifier voltage (V_amp) does not reach the target voltage (V_target) or the new temperature data (T_data) does not reach the target temperature (T_target), the process can enter the 6th step (S6) again.

[0123] FIGS. 7 to 10 are graphs of amplifier voltage and temperature data according to one embodiment of the present invention.

[0124] FIGS. 7 to 10 do not show specific simulation results or measured values ​​of the amplifier voltage (V_amp) and temperature data (T_data). FIGS. 7 to 10 illustrate the process in which the amplifier voltage (V_amp) and temperature data (T_data) change according to the driving of the timing driving unit (400) of the data driving unit (300) described in FIG. 6.

[0125] As described above in FIG. 6, based on the bias control signal (S_bias) and the analog data signal (S_data_a), the data driving unit (300) can generate an amplifier voltage (V_amp).

[0126] Figure 7 illustrates the process of performing the first fourth step (S4-1).

[0127] The amplifier (AMP) of the output amplifier section (OA) has a first slew rate (SR1) and can generate a first amplifier voltage (V_amp1). When a sampling section control signal (S_sam) is input to the sampling section (SAM), the sampling section (SAM) can sample the first amplifier voltage (V_amp1). The sampling section (SAM) can generate a first sampling voltage (V_sam1) by sampling the first amplifier voltage (V_amp1).

[0128] In the first fourth step (S4-1), the timing control unit (400) can determine whether the first sampling voltage (V_sam1) has reached the target voltage (V_target). As shown in FIG. 7, if the first sampling voltage (V_sam1) has not reached the target voltage (V_target), the sixth step (S6) can be entered.

[0129] As described above, in step 6 (S6), the timing control unit (400) can reset the data driver control signal (DCS). Since the data driver control signal (DCS) is reset, the bias control signal (S_bias) generated based on the data driver control signal (DCS) can also be reset. Due to the reset bias control signal (S_bias), the bias voltage (V_bias) supplied to the output amplifier unit (OA) of the data driver (300) can be increased. Meanwhile, the image data (IDATA) may remain the same.

[0130] After performing the 6th step (S6), the data driving unit (300) performs the 1st step (S1), the 2nd step (S2), and the 3rd step (S4), and can enter the second 4th step (S4-2). FIG. 8 illustrates the process of performing the second 4th step (S4-2).

[0131] The amplifier (AMP) of the output amplifier section (OA) has a second slew rate (SR2) and can generate a second amplifier voltage (V_amp2). Due to the reset bias control signal (S_bias), the second slew rate (SR2) may be greater than the first slew rate (SR1). Accordingly, the second amplifier voltage (V_amp2) may be greater than the first amplifier voltage (V_amp1).

[0132] When a sampling unit control signal (S_sam) is input to the sampling unit (SAM), the sampling unit (SAM) can sample the second amplifier voltage (V_amp2). The sampling unit (SAM) can generate a second sampling voltage (V_sam2) by sampling the second amplifier voltage (V_amp2).

[0133] In the second fourth step (S4-2), the timing control unit (400) can determine whether the second sampling voltage (V_sam2) has reached the target voltage (V_target). As shown in FIG. 7, if the first sampling voltage (V_sam1) has not reached the target voltage (V_target), the sixth step (S6) can be entered.

[0134] As described above, in step 6 (S6), the timing control unit (400) can reset the data driver control signal (DCS). Since the data driver control signal (DCS) is reset, the bias control signal (S_bias) generated based on the data driver control signal (DCS) can also be reset. Due to the reset bias control signal (S_bias), the bias voltage (V_bias) supplied to the output amplifier unit (OA) of the data driver (300) can be increased. Meanwhile, the image data (IDATA) may remain the same.

[0135] After performing the 6th step (S6), the data driving unit (300) performs the 1st step (S1), the 2nd step (S2), and the 3rd step (S4), and can enter the third 4th step (S4-3). FIG. 9a illustrates the process of performing the third 4th step (S4-3).

[0136] The amplifier (AMP) of the output amplifier section (OA) has a third slew rate (SR3) and can generate a third amplifier voltage (V_amp3). Due to the reset bias control signal (S_bias), the third slew rate (SR3) may be greater than the second slew rate (SR2). Accordingly, the third amplifier voltage (V_amp3) may be greater than the second amplifier voltage (V_amp2).

[0137] When a sampling unit control signal (S_sam) is input to the sampling unit (SAM), the sampling unit (SAM) can sample the third amplifier voltage (V_amp3). The sampling unit (SAM) can generate the third sampling voltage (V_sam3) by sampling the third amplifier voltage (V_amp3).

[0138] In the third fourth step (S4-3), the timing control unit (400) can determine whether the third sampling voltage (V_sam3) has reached the target voltage (V_target). As shown in FIG. 9a, if the third sampling voltage (V_sam3) has reached the target voltage (V_target), the system can enter the fifth step (S5) without entering the sixth step (S6).

[0139] FIG. 9b illustrates the process of performing the first fifth step (S5-1). In the first fifth step (S5-1), the timing control unit (400) can determine whether the first temperature data (T_data1) has reached the target temperature (T_target). As shown in FIG. 9b, if the first temperature data (T_data) has not reached the target temperature (T_target), the process can enter the sixth step (S6) again.

[0140] As described above, in step 6 (S6), the timing control unit (400) can reset the data driver control signal (DCS). Since the data driver control signal (DCS) is reset, the bias control signal (S_bias) generated based on the data driver control signal (DCS) can also be reset. Due to the reset bias control signal (S_bias), the bias voltage (V_bias) supplied to the output amplifier unit (OA) of the data driver (300) can be increased. Meanwhile, the image data (IDATA) may remain the same.

[0141] After performing the 6th step (S6), the data driving unit (300) performs the 1st step (S1), the 2nd step (S2), and the 3rd step (S4), and can enter the third 4th step (S4-3). FIG. 10a illustrates the process of performing the fourth 4th step (S4-4).

[0142] The amplifier (AMP) of the output amplifier section (OA) has a fourth slew rate (SR4) and can generate a fourth amplifier voltage (V_amp4). Due to the reset bias control signal (S_bias), the fourth slew rate (SR4) may be greater than the third slew rate (SR3). Accordingly, the fourth amplifier voltage (V_amp4) may be greater than the third amplifier voltage (V_amp3). When a sampling section control signal (S_sam) is input to the sampling section (SAM), the sampling section (SAM) can sample the fourth amplifier voltage (V_amp4). The sampling section (SAM) can generate a fourth sampling voltage (V_sam4) by sampling the fourth amplifier voltage (V_amp4).

[0143] In the fourth step 6 (S6-4), the timing control unit (400) can determine whether the fourth sampling voltage (V_sam4) has reached the target voltage (V_target). As shown in FIG. 10a, if the fourth sampling voltage (V_sam4) has reached the target voltage (V_target), the second step 5 (S5-2) can be entered.

[0144] FIG. 10b illustrates the process of performing the second fifth step (S5-2). In the second fifth step (S5-2), the timing control unit (400) can determine whether the second temperature data (T_data2) has reached the target temperature (T_target). Due to the reset bias control signal (S_bias), the amplifier (AMP) increases the slew rate and amplifier voltage (V_amp), and the second temperature data (T_data2) may be greater than the first temperature data (T_data1).

[0145] As illustrated in FIG. 10b, when the second temperature data (T_data2) reaches the target temperature (T_target), the timing control unit (400) can supply the current data driving unit control signal (DCS) to the data driving unit (300). Accordingly, the data driving unit (300) can maintain the current amplifier voltage (V_amp) and the current temperature data (T_data).

[0146] In conclusion, the timing control unit (400) can reset the bias control signal (S_bias) until the amplifier voltage (V_amp) reaches the target voltage (V_target) and simultaneously the temperature data (T_data) reaches the target temperature (T_target). Accordingly, the timing control unit (400) can reset the bias control signal (S_bias) and control the output amplifier unit (OA) of the data driving unit (300). Thus, the data driving unit (300) can be driven stably by checking the optimal value of the bias voltage (V_bias) inside the display device and automatically setting the bias voltage (V_bias) to the optimal value.

[0147] Typically, the load of the display panel (100) may vary depending on the physical conditions of the display panel (100) to which the data driving unit (300) is connected. For example, the load of the display panel (100) may vary depending on the size of the display panel (100).

[0148] In this case, the slew rate of the data driver (300) connected to the display panel (100) may change. In particular, the slew rate of the amplifier (AMP) of the output amplifier section (OA) of the data driver (300) may change.

[0149] Specifically, when the amplifier voltage (V_amp) output from the data driving unit (300) functions as the data voltage (V_data), the speed at which the display panel (100) responds to the data voltage (V_data) and outputs an image may be delayed. Alternatively, the data voltage (V_data) input to the display panel (100) may be smaller than the voltage required to drive the display panel (100). Accordingly, the display panel (100) may not be driven stably, and the quality of the display panel (100) may be degraded.

[0150] Alternatively, even if the amplifier voltage (V_amp) output from the data driving unit (300) functions smoothly as the data voltage (V_data), the temperature data (T_data) may not satisfy certain conditions. In this case, the data driving unit (300) may not operate stably, and the quality of the display panel (100) may be degraded.

[0151] To improve this, it was necessary to adjust the output of the output amplifier section (OA) of the data driving unit (300) while directly checking the magnitude of the amplifier voltage (V_amp) of the data driving unit (300) and the temperature data (T_data) of the data driving unit (300).

[0152] However, the present invention allows the timing control unit (400) to automatically reset the bias control signal (S_bias) until the amplifier voltage (V_amp) reaches the target voltage (V_target) and simultaneously the temperature data (T_data) reaches the target temperature (T_target). Accordingly, even if the physical conditions of the display panel (1000) change, the timing control unit (400) can automatically set the amplifier voltage (V_amp) to an optimal value and the temperature data (T_data) to an optimal value.

[0153] Accordingly, depending on the physical conditions of the display panel (1000), the data driving unit (300) can be stably driven and the quality of the display panel (100) can be improved even without setting the data driving unit (300) externally.

[0155] Although embodiments of the present invention have been described in more detail with reference to the attached drawings, the present invention is not necessarily limited to these embodiments and may be modified in various ways within the scope of the technical spirit of the present invention. Accordingly, the embodiments disclosed in the present invention are intended to explain, not limit, the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of protection of the present invention shall be interpreted by the claims, and all technical spirits within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0157] 100: Display panel 200: Gate drive unit 300: Data driver 400: Timing control unit TX: Transmitter RX: Receiving part LOGIC: Logic part OA: Output amplifier section SAM: Sampling unit TEM: Temperature sensor

Claims

Claim 1 A display device comprising: a display panel including a plurality of pixels; a data driver that supplies a data voltage to the display panel and generates a sampling voltage and temperature data; and a timing control unit that supplies a bias control signal and image data to the data driver and varies the bias control signal based on the sampling voltage and the temperature data, wherein the data driver includes: an output amplifier unit that generates an amplifier voltage based on the bias control signal and the image data; a sampling unit that samples the amplifier voltage at a preset period and outputs a sampling voltage; and a temperature sensor that measures the temperature of the data driver and generates the temperature data. Claim 2 A display device according to claim 1, wherein when the sampling voltage is smaller than a preset target voltage, the timing control unit adjusts the bias control signal so that the bias voltage supplied to the output amplifier unit increases. Claim 3 A display device according to claim 1, wherein when the temperature data is smaller than a preset target temperature, the timing control unit adjusts the bias control signal so that the bias voltage supplied to the output amplifier unit is increased. Claim 4 A display device according to claim 1, wherein if the sampling voltage is smaller than a preset target voltage or the temperature data is smaller than a preset target temperature, the bias voltage supplied to the output amplifier increases. Claim 5 A display device according to claim 1, wherein the data driving unit further comprises: a logic unit that converts a serial data signal provided from the timing control unit into a parallel data signal; and a digital-to-analog converter that converts the parallel data signal into an analog data signal. Claim 6 In claim 5, the output amplifier comprises: a bias circuit that outputs a bias voltage in response to the bias control signal; an amplifier that generates the amplifier voltage based on the analog data signal and the bias voltage; and an output unit that stabilizes the amplifier voltage, the display device. Claim 7 In claim 6, the amplifier comprises: a first input terminal connected to the analog data signal; a second input terminal connected to the bias voltage; and an output terminal that outputs the amplifier voltage and transmits the amplifier voltage to the output unit, the display device. Claim 8 In claim 6, the output unit comprises a first transistor and a second transistor, and the gate electrode of the first transistor and the gate electrode of the second transistor are connected to the amplifier voltage, a display device. Claim 9 A display device according to claim 1, wherein the data driving unit further includes an analog-to-digital converter that converts the sampling voltage into a digital signal and outputs a digital sampling voltage. Claim 10 In claim 9, the display device further comprises a storage unit that stores the digital sampling voltage, wherein the data driving unit further comprises the data driving unit. Claim 11 A method for driving a display device, comprising: a step of generating an amplifier voltage and sampling the amplifier voltage by a data driver based on a bias voltage and an analog data signal; a step of generating temperature data by measuring the temperature of the data driver and / or the surroundings of the data driver at a preset period; a step of determining whether the amplifier voltage has reached a target voltage at the time of sampling the amplifier voltage; a step of determining whether the temperature data has reached a target temperature; and a step of resetting a bias control signal that controls the magnitude of the bias voltage according to the determination result of the amplifier voltage and the target voltage and the determination result of the temperature data and the target temperature. Claim 12 A driving method for a display device according to claim 11, wherein if the amplifier voltage does not reach the target voltage, the bias control signal is reset and provided to the data driving unit. Claim 13 A driving method for a display device according to claim 12, wherein the bias voltage increases in response to the reset bias control signal. Claim 14 A driving method for a display device according to claim 12, wherein if the temperature data does not reach the target temperature, the bias control signal is reset and the bias voltage is increased. Claim 15 A driving method for a display device according to claim 11, wherein when the amplifier voltage reaches the target voltage and the temperature data reaches the target temperature, the bias control signal corresponding to the bias voltage is supplied to the data driving unit.

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