KR20170065088A

KR20170065088A - Display-device, apparatus and method for processing spread spectrum signal of the display-device

Info

Publication number: KR20170065088A
Application number: KR1020150171020A
Authority: KR
Inventors: 김백환
Original assignee: 엘지디스플레이 주식회사
Priority date: 2015-12-02
Filing date: 2015-12-02
Publication date: 2017-06-13

Abstract

The present invention relates to a display apparatus and an apparatus and method for processing a spread spectrum signal of the display apparatus, and in applying a spread spectrum to an externally input clock signal (CLK) to improve electromagnetic interference (EMI) A clock signal CLK is modulated according to a modulation frequency and a modulation rate different from each other according to a pattern of data and a control signal is generated using a modulated spectrum clock signal (Spectrum CLK) In the case of a weak image data pattern, wobble noise recognized in a specific image data pattern can be improved while the effect of improving electromagnetic interference (EMI) is reduced by reducing the swing of the scan signal by the spread spectrum.

Description

TECHNICAL FIELD [0001] The present invention relates to a spread spectrum signal processing apparatus and method for a display apparatus, a display apparatus, and a spread spectrum signal processing apparatus.

The embodiments are directed to a display apparatus and an apparatus and method for processing a spread spectrum signal of the display apparatus.

2. Description of the Related Art [0002] As an information-oriented society develops, there have been various demands for a display device for displaying images. Recently, a liquid crystal display (LCD), a plasma display panel (PDP) And various display devices such as an organic light emitting display (OLED) device are used.

Such a display device includes a display panel in which pixels defined in a region where gate lines and data lines are arranged and which are defined in regions where gate lines and data lines cross each other, a gate driver for driving gate lines, A timing controller for controlling the timing of driving the gate driver and the data driver, and the like.

Here, the gate driver outputs a gate signal for driving each gate line in accordance with the control signal received from the timing controller, and the timing controller generates the above-described control signal using the clock signal received from the outside.

In this case, when the frequency of the clock signal increases in a high-resolution display device as the gate signal is outputted by the control signal generated by using the same clock signal, the energy level is concentrated and EMI (Electro-Magnetic Interference) This can reduce electromagnetic interference (EMI) by using a modulated clock signal by applying a spread spectrum.

However, due to the application of spread spectrum, as the scan signal fluctuates, the charging timing is regularly varied for each gate line, causing a problem of being recognized as Wavy Noise on the screen. This is recognized as a severe Wavy Noise in a specific pattern such as a white monochromatic pattern, and an improvement method is required.

It is an object of the present embodiments to provide a display device for preventing occurrence of Wavy Noise due to application of a spread spectrum while improving electromagnetic interference (EMI) by applying a spread spectrum, and a spread spectrum signal processing device And a method.

It is an object of the embodiments of the present invention to provide a display device capable of simultaneously solving electromagnetic interference (EMI) and waveleness noise by changing the modulation frequency and the frequency modulation rate of a spread spectrum in real time, and a spread spectrum And to provide a signal processing apparatus and method.

One embodiment includes a spread spectrum integrated circuit that receives a clock signal from the outside and modulates the received clock signal according to the stored modulation frequency and frequency modulation rate and outputs a modulated spectral clock signal, And a timing controller for generating a signal for controlling at least one of the data driver and the data driver, wherein the timing controller resets the modulation frequency and the frequency modulation rate according to the pattern of the input image data, And transmits the signal to a spectrum integrated circuit to update a value stored in the spread spectrum integrated circuit.

In a spread spectrum signal processing apparatus of such a display device, the spread spectrum integrated circuit can periodically check the stored modulation frequency and frequency modulation rate and modulate the received clock signal based on the stored modulation frequency and frequency modulation rate.

In the spread spectrum signal processing apparatus of such a display apparatus, the timing controller can reset a predetermined modulation frequency and a frequency modulation ratio to a value lower than a preset value according to a pattern of input image data, The modulation frequency and the frequency modulation rate corresponding to the value of the lookup table can be stored in the lookup table and the modulation frequency and the frequency modulation rate can be reset according to the value stored in the lookup table.

The timing controller can reset the modulation frequency and the modulation rate of the frequency to a value lower than a predetermined value if the input image data is low tone image data. If the temperature of the system is higher than a predetermined temperature, the modulation frequency and the modulation rate Can be reset to a value lower than a predetermined value.

In another embodiment, there is provided a method comprising: receiving a clock signal from the outside; modulating the received clock signal according to the modulation frequency and frequency modulation rate stored in the memory and outputting the modulated spectrum clock signal; Wherein the step of outputting the modulated spectral clock signal comprises the steps of resetting the modulation frequency and the frequency modulation rate stored in the memory according to the pattern of the input image data, The method of processing a spectrum signal of a display device that modulates a received clock signal according to the present invention.

Another embodiment is a display panel including a plurality of pixels arranged in an intersecting relationship with a plurality of gate lines and a plurality of data lines and arranged in a region where gate lines and data lines cross each other, A data driver for supplying a data voltage to a plurality of data lines and a timing controller for generating a control signal for controlling the driving of the gate driver and the data driver using a clock signal received from the outside, A control unit for modulating a clock signal received from the outside according to a predetermined modulation frequency and a modulation rate of the frequency and generating a control signal using the modulated spectrum clock signal, A display device for generating a control signal It may provide.

In this display device, the timing controller includes a memory for storing a modulation frequency and a frequency modulation ratio, a clock signal modulation unit for modulating a clock signal received from the outside according to a modulation frequency and a frequency modulation rate stored in the memory, And a spread spectrum setting unit for resetting the modulation frequency and the frequency modulation rate stored in the memory according to the pattern of the image data.

According to the present embodiments, a display device that improves electromagnetic interference (EMI) and simultaneously prevents a Wavy Noise by applying a spread spectrum modulation frequency and a frequency modulation ratio differently according to a specific pattern of image data, And a spread spectrum signal processing apparatus and method for the display apparatus.

According to the embodiments of the present invention, due to the functional expansion that changes the modulation frequency and the frequency modulation rate of the spread spectrum in real time, the spread spectrum integrated circuit can be flexibly applied to the product, and the electromagnetic interference (EMI) and the wavy noise A display apparatus for solving the problem simultaneously, and an apparatus and a method for processing a spread spectrum signal of the display apparatus.

1 is a diagram showing a schematic configuration of a display device according to the present embodiments.
2 is a diagram showing a schematic configuration of a display device including a spread spectrum integrated circuit according to the present embodiments.
3 is a diagram showing waveforms and energy levels of a clock signal to which a spread spectrum is not applied.
4 is a diagram showing an example of a modulation frequency and a frequency modulation ratio of a spread spectrum.
5 is a diagram showing a waveform and an energy level of a clock signal to which a spread spectrum is applied.
6 is a diagram showing an example of a scan signal to which a spread spectrum is applied.
7 is a diagram illustrating an example in which wavelet noise is generated by a scan signal to which a spread spectrum is applied.
8 is a diagram showing a configuration of a spread spectrum signal processing apparatus of a display apparatus according to the present embodiments.
9 is a diagram showing an example of a modulation frequency and a frequency modulation ratio of a spread spectrum reset according to the present embodiments.
10 is a diagram showing an example of a scan signal to which a spread spectrum reset according to the present embodiments is applied.
11 is a block diagram showing a configuration of a timing controller for processing a spread spectrum signal according to the present embodiments.
12 and 13 are flowcharts illustrating a process of a spread spectrum signal processing method of a display apparatus according to the present embodiments.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In the drawings, like reference numerals are used to denote like elements throughout the drawings, even if they are shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the components from other components, and the terms do not limit the nature, order, order, or number of the components. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; intervening "or that each component may be" connected, "" coupled, "or " connected" through other components.

FIG. 1 shows a schematic system configuration of a display apparatus 100 according to the present embodiments.

1, a display device 100 according to an embodiment of the present invention includes a display panel 100 in which a plurality of pixels (pixels 200) are arranged and a plurality of gate lines GL and a plurality of data lines DL are arranged A gate driver 120 for driving a plurality of gate lines GL and a data driver 130 for supplying a data voltage to a plurality of data lines DL, And a timing controller (T-CON, 140) for controlling the timing controller 130.

The gate driver 120 sequentially drives the plurality of gate lines GL by sequentially supplying scan signals to the plurality of gate lines GL.

The data driver 130 drives the plurality of data lines DL by supplying data voltages to the plurality of data lines DL.

The timing controller 140 supplies various control signals to the gate driver 120 and the data driver 130 to control the gate driver 120 and the data driver 130.

The timing controller 140 starts scanning according to the timing implemented in each frame, switches the input image data input from the outside according to the data signal format used by the data driver 130, and outputs the converted image data And controls the data driving at a proper time according to the scan.

The gate driver 120 sequentially supplies a scan signal of an ON voltage or an OFF voltage to the plurality of gate lines GL in accordance with the control of the timing controller 140, Respectively.

The gate driver 120 may be located on one side or both sides of the display panel 110 according to the driving method.

In addition, the gate driver 120 may include one or more gate driver integrated circuits.

Each gate driver integrated circuit may be connected to a bonding pad of the display panel 110 by a Tape Automated Bonding (TAB) method or a chip on glass (COG) method, or may be connected to a GIP (Gate In Panel) Type and may be disposed directly on the display panel 110. [ In addition, they may be integrated in the display panel 110, or may be implemented in a chip-on-film (COF) manner, which is mounted on a film connected to the display panel 110.

When the specific gate line GL is opened, the data driver 130 converts the image data received from the timing controller 140 into analog data voltages and supplies the data voltages to the plurality of data lines DL, .

The data driver 130 may include at least one source driver integrated circuit to drive a plurality of data lines DL.

Each source driver integrated circuit may be connected to a bonding pad of the display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) And may be integrated and disposed on the display panel 110. [

In addition, each source driver integrated circuit may be implemented in a chip-on-film (COF) manner. In this case, one end of each source driver integrated circuit is bonded to at least one source printed circuit board, and the other end is bonded to the display panel 110.

The timing controller 140 outputs various timing signals including a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input data enable (DE) signal, a clock signal CLK, (E.g., a host system).

The timing controller 140 may switch the input video data inputted from the outside according to the data signal format used by the data driver 130 and output the converted video data to the gate driver 120 and the data driver 130 A timing signal such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input data enable signal DE and a clock signal CLK to generate various control signals, (120) and the data driver (130).

For example, in order to control the gate driver 120, the timing controller 140 generates a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable signal GOE : Gate Output Enable), and the like.

Here, the gate start pulse GSP controls the operation start timing of one or more gate driver integrated circuits constituting the gate driver 120. The gate shift clock GSC is a clock signal commonly input to one or more gate driver integrated circuits, and controls the shift timing of the scan signal (gate pulse). The gate output enable signal GOE specifies the timing information of one or more gate driver ICs.

The timing controller 140 includes a source start pulse SSP, a source sampling clock SSC, a source output enable signal SOE, Output enable (DCS) data control signals.

Here, the source start pulse SSP controls the data sampling start timing of one or more source driver integrated circuits constituting the data driver 130. The source sampling clock SSC is a clock signal for controlling sampling timing of data in each of the source driver integrated circuits. The source output enable signal SOE controls the output timing of the data driver 130.

The timing controller 140 is connected to a source printed circuit board to which a source driver integrated circuit is bonded and a control printed circuit (not shown) connected via a connection medium such as a flexible flat cable (FFC) or a flexible printed circuit And may be disposed on a substrate (Control Printed Circuit Board).

A power controller (not shown) for controlling various voltages or currents to supply or supply various voltages or currents to the display panel 110, the gate driver 120, the data driver 130, . These power controllers are also referred to as power management integrated circuits.

The timing controller 140 generates a control signal for driving the gate driver 120 using a clock signal CLK having a constant waveform in generating a control signal for driving the gate driver 120. [ The gate driver 120 outputs a scan signal in accordance with a control signal of the timing controller 140 to drive each gate line GL.

At this time, when the timing controller 140 drives the high-resolution display device 100, the frequency of the clock signal CLK received from the outside is increased to increase instantaneous power consumption, thereby increasing electromagnetic interference (EMI) exist.

In order to prevent such electromagnetic interference (EMI) from occurring, the timing controller 140 generates a clock signal (hereinafter referred to as a "clock signal ") modulated by applying a spread spectrum without using the same clock signal CLK, Quot; spectrum clock signal (Spectrum CLK) ") to generate a control signal for driving the gate driver 120.

The spread spectrum is a technique for periodically modulating the frequency of a clock signal CLK input from the outside. When the frequency of the externally input clock signal (CLK) is modulated by the spread spectrum, the frequency band of the modulated spectrum clock signal (Spectrum CLK) spreads widely on the frequency axis. Electromagnetic interference (EMI) is usually concentrated at the maximum power of a frequency, so that by lowering the maximum power of the frequency through the spread spectrum, the level of electromagnetic interference (EMI) distributed over the maximum power of the frequency is also lowered.

The spread spectrum method includes a center spreading method and a down spreading method.

In the center spreading method, the frequency is modulated by the same magnitude up and down around the center frequency, and the down spreading method is a method of modulating the frequency around a frequency lower than the center frequency. In the present embodiments, a method of modulating the frequency by the center spreading method is described, but the present invention is not limited thereto.

It is possible to provide an effect of improving the electromagnetic interference (EMI) by dispersing the energy level of the scan signal by applying the spread spectrum described above.

2 shows a schematic configuration of a display device 100 including a spread spectrum integrated circuit according to the present embodiments.

2, the display device 100 according to the present embodiment includes a display panel 110, a gate driver 120, a data driver 130 and a timing controller 140, a timing controller 140, And a spread spectrum integrated circuit 150 that provides a modulated spectral clock signal (Spectrum CLK).

The timing controller 140 transfers the clock signal CLK received from the outside to the spread spectrum integrated circuit 150. [

The spread spectrum integrated circuit 150 receives the clock signal CLK from the timing controller 140 and outputs the received clock signal CLK to the modulation frequency of the spread spectrum integrated circuit 150, Modulation (or frequency deviation).

Here, the modulation frequency means the number of times the received clock signal (CLK) is modulated for a unit time, and is a reciprocal of the frequency modulation period.

The frequency modulation rate refers to the modulation rate of the maximum modulation frequency with respect to the center frequency of the modulated spectrum clock signal (Spectrum CLK) or the modulation rate of the minimum modulation frequency with respect to the center frequency of the modulated spectrum clock signal (Spectrum CLK). In this case, the frequency modulation rate is expressed in percentage units.

For example, if the center frequency is 100 kHz, the maximum modulation frequency is 105 kHz, and the minimum modulation frequency is 95 kHz, the frequency modulation rate is ± 5%. Accordingly, the frequency modulation rate means a ratio of the frequency of the modulated spectrum clock signal (Spectrum CLK) to the frequency of the input clock signal (CLK) and the frequency of the input clock signal (CLK).

In this specification, the modulation frequency and the frequency modulation rate are collectively referred to as "frequency modulation reference ".

The spread spectrum integrated circuit 150 transmits a spectrum clock signal (Spectrum CLK) obtained by modulating the clock signal (CLK) received from the timing controller 140 to the timing controller 140.

The timing controller 140 generates a control signal for driving the gate driver 120 using the spectrum clock signal (Spectrum CLK) received from the spread spectrum integrated circuit 150. Accordingly, the gate driver 120 outputs a scan signal according to a control signal generated using a frequency-modulated spectrum clock signal (Spectrum CLK) from the timing controller 140, thereby distributing the energy level to generate electromagnetic interference (EMI ) Should not occur.

The spread spectrum integrated circuit 150 may be disposed separately from the timing controller 140 as shown in FIG. 2, but may be disposed within the timing controller 140 to receive the clock signal input to the timing controller 140 Modulated and output.

Hereinafter, the spread spectrum integrated circuit 150 modulates the input clock signal CLK and the electromagnetic interference (EMI) improvement effect by frequency modulation and its problem will be described with reference to FIG. 3 to FIG.

3 shows the waveform and the energy level of the clock signal CLK received from the timing controller 140 from the outside, and shows a case in which the spread spectrum is not applied.

3, the timing controller 140 receives a clock signal CLK having a predetermined waveform from the outside and generates a control signal for driving the gate driver 120 using the received clock signal CLK . Since the control signal is generated using the clock signal CLK having a constant waveform, as the frequency of the clock signal CLK increases, the energy level is concentrated as shown in FIG. 3 and electromagnetic interference (EMI) is generated.

FIG. 4 shows an example of a spread spectrum modulation frequency and a frequency modulation ratio.

Referring to FIG. 4, FIG. 4 shows a spread spectrum center spreading method, in which f ₀ denotes a center frequency, a modulation frequency is 50 kHz, and a frequency modulation rate is ± 0.5%. Since the modulation frequency is 50 kHz, the frequency modulation period is 1 / 50,000 seconds.

That is, the maximum modulated frequency of the modulated spectrum clock signal (Spectrum CLK) modulates the input clock signal (CLK) with a modulation period of 1 / 50,000 seconds as the center frequency f ₀ is increased by 0.5% Is a frequency at which the center frequency f ₀ is reduced by 0.5%.

If the input clock signal CLK is modulated according to the modulation frequency and the frequency modulation rate shown in FIG. 4, the modulated spectrum clock signal (Spectrum CLK) is not a fixed waveform but a waveform that fluctuates regularly.

5 shows the waveform of the spectrum clock signal (Spectrum CLK) modulated by applying the spread spectrum and the distribution of the energy level thereof.

Referring to FIG. 5, the spectrum clock signal (Spectrum CLK) has a frequency different from that of the input clock signal CLK and has different waveforms as indicated by a dotted line in FIG.

Therefore, the energy level according to the spectrum clock signal (Spectrum CLK) is dispersed to lower the maximum power, thereby lowering the level of electromagnetic interference (EMI).

As described above, the spread spectrum integrated circuit 150 can provide the effect of improving the electromagnetic interference (EMI) by modulating the frequency of the clock signal CLK input from the outside, There is a problem that the charge time is regularly changed for each gate line GL due to the fluctuation d of the scan signal to be driven, and thus it is recognized as a Wavy Noise on the screen.

FIG. 6 shows an example of a scan signal output according to a control signal generated using a modulated spectrum clock signal (Spectrum CLK), and FIG. 7 shows an example of a scan signal generated by driving a gate line GL in accordance with the scan signal. (Wavy Noise) occurs.

6, the timing controller 140 generates a control signal by using a spectral clock signal (Spectrum CLK) whose frequency is not a clock signal CLK of a predetermined waveform, so that the control signal of the timing controller 140 The scan signal output according to the scan signal is shaken.

The scan signal fluctuates, so that the charging time periodically varies for each gate line GL. As a result, a Wavy Noise may occur on the screen as shown in FIG.

Therefore, the present embodiments reduce the electromagnetic interference (EMI) by generating the control signal using the modulated spectrum clock signal (Spectrum CLK), and at the same time, the problem of generating the wavelike noise due to the shaking of the scan signal And a spread spectrum signal processing apparatus and method for the display apparatus (100).

FIG. 8 shows a configuration of a spread spectrum signal processing apparatus according to the present embodiments.

The spread spectrum signal processing apparatus according to the present embodiment includes a timing controller 140 and a spread spectrum integrated circuit 150 in which the spread spectrum integrated circuit 150 is disposed separately from the timing controller 140 An embodiment will be described.

The present embodiments apply a spectrum spread to reduce electromagnetic interference (EMI) and generate a clock signal in accordance with a relaxed frequency modulation reference while avoiding electromagnetic interference (EMI) in a pattern vulnerable to Wavy Noise. (CLK) is modulated so that no Wavy Noise occurs.

That is, by modulating the clock signal (CLK) by applying a different modulation frequency and a frequency modulation rate according to a pattern of inputted image data instead of a fixed modulation frequency and a frequency modulation rate, electromagnetic interference (EMI) and Wavy Noise ) To solve all the problems.

Referring to FIG. 8, the timing controller 140 receives image data and a clock signal CLK from the outside.

Upon receipt of the image data from the outside, the timing controller 140 analyzes the pattern of the received image data to determine whether it is image data that is weak to the Wavy Noise.

For example, image data that is vulnerable to Wavy Noise includes low-tone image data such as a white monochromatic pattern. Also, if the temperature of the system is high, the jitter may increase and be recognized as a Wavy Noise.

That is, the timing controller 140 analyzes a pattern of image data input from the outside or a temperature of the system, and determines whether or not it is vulnerable to a wavy noise.

The timing controller 140 transmits the clock signal CLK input from the outside to the spread spectrum integrated circuit 150 in the manner described above in the case of image data that is not susceptible to Wavy Noise. The spread spectrum integrated circuit 150 modulates the received clock signal CLK according to the modulation frequency and the frequency modulation rate preset in the register and transmits the modulated spectrum clock signal Spectrum CLK to the timing controller 140 do.

When the image data received from the outside is image data weak to the Wavy Noise, the timing controller 140 resets the predetermined modulation frequency and the frequency modulation rate to a value lower than a predetermined value.

For example, when the predetermined modulation frequency is 50 kHz and the frequency modulation rate is ± 0.5%, the modulation frequency is reset to 40 kHz and the frequency modulation rate is reset to ± 0.25%.

In this case, the values to be reset can be stored in the lookup table, the modulation frequency and the modulation rate corresponding to the pattern of the image data, and the modulation frequency and the modulation rate can be reset according to the values stored in the lookup table. As shown in FIG.

Pattern Output frequency Frequency Deviation Modulation Frequency Normal Pattern 80MHz 0.5% 50 kHz Wavy Vulnerable Pattern 0.25% 40kHz

The look-up table may also be configured with a range of temperature of the system and modulation frequency and frequency modulation rate corresponding to each range.

The timing controller 140 transmits the reset modulation frequency and the frequency modulation rate to the spread spectrum integrated circuit 150 to update the modulation frequency and the frequency modulation rate stored in the register of the spread spectrum integrated circuit 150. [

The spread spectrum integrated circuit 150 periodically checks the modulation frequency and frequency modulation rate stored in the register and modulates the clock signal CLK received from the timing controller 140 according to the modulation frequency and frequency modulation rate stored in the register do. And transmits the modulated spectral clock signal (Spectrum CLK) to the timing controller 140.

Accordingly, when displaying image data weak to Wavy Noise, the timing controller 140 generates a control signal using a modulated spectrum clock signal (Spectrum CLK) by applying a relaxed frequency modulation reference do. Then, according to the generated control signal, the gate driver 120 outputs a scan signal so that the swing of the scan signal is reduced, thereby preventing a Wavy Noise from occurring.

At this time, in resetting the modulation frequency and the modulation factor, the timing controller 140 resets the modulation frequency and the modulation factor of the frequency within a range that maintains the effect of reducing electromagnetic interference (EMI). Therefore, even when the image data of a specific pattern is displayed, the effect of reducing the electromagnetic interference (EMI) can be maintained, and the Wavy noise can be prevented from occurring.

In addition, when the input image data is not vulnerable to Wavy Noise after resetting the modulation frequency and the modulation rate, the timing controller 140 sets the reset modulation frequency and the frequency modulation rate as initial values And transmits the reset modulation frequency and the frequency modulation rate to the spread spectrum integrated circuit 150 to update the value stored in the register of the spread spectrum integrated circuit 150. [

Therefore, by modulating the clock signal CLK according to the modulation frequency and the modulation rate set according to the pattern of the input image data, the electromagnetic interference (EMI) is reduced while the Wavy noise is not generated.

9 and 10 show an example of a relaxed frequency modulation reference and an example of a corresponding scan signal.

Referring to FIG. 9, it is shown that the modulation frequency is 40 kHz and the frequency modulation rate is ± 0.25%.

When the pattern of the video data received from the outside by the timing controller 140 is a pattern weak to the Wavy noise, as shown in FIG. 9, by setting the modulation frequency and the frequency modulation rate lower than a predetermined value The degree of modulation of the frequency of the clock signal CLK input from the outside can be reduced.

10, a scan signal is output in accordance with a control signal generated using a spectrum clock signal (Spectrum CLK) modulated according to the reset modulation frequency and the frequency modulation rate. Thus, the scan signal is supplied to the spread spectrum integrated circuit 150 (Fig. 6), the shaking is reduced.

Accordingly, since the shaking of the scan signal supplied to each gate line GL is reduced, even in the case of image data that is vulnerable to the Wavy noise, the Wavy noise can be prevented from being generated, (EMI) reduction effect.

11 shows an embodiment in which the function of the spread spectrum integrated circuit 150 according to the present embodiments is disposed inside the timing controller 140. [

11, a timing controller 140 for processing a spread spectrum signal according to the present embodiment includes a memory 141, a clock signal modulator 142, a spread spectrum setting unit 143, (144).

The memory 141 stores the modulation frequency and frequency modulation rate for applying the spread spectrum.

The modulation frequency and the frequency modulation rate can be stored as two or more different values depending on the pattern of input image data or the temperature of the system. At this time, the modulation frequency and the frequency modulation rate corresponding to the temperature of the system where the pattern of the image data weak to the Wavy Noise or the jitter of the system increases, are stored as values lower than the values corresponding to the general image data pattern .

The clock signal modulator 142 receives the clock signal CLK from the outside and modulates the received clock signal CLK in accordance with the modulation frequency and the frequency modulation rate stored in the memory 141. Then, the modulated spectrum clock signal (Spectrum CLK) is transmitted to the control signal generator 144.

The control signal generator 144 generates a control signal using the modulated spectrum clock signal (Spectrum CLK).

For example, a spectrum clock signal (Spectrum CLK) is used to generate a control signal for driving the gate driver 120, and transmits the control signal to the gate driver 120.

The gate driver 120 generates and outputs a scan signal in accordance with the output control signal. Therefore, the scan signal is output according to the control signal generated using the modulated spectral clock signal (Spectrum CLK), so that the scan signal is shaken and wavy noise is generated in the specific image data pattern.

Therefore, in the case of a video data pattern that is weak to the Wavy Noise, it is necessary to apply the modulation frequency and the frequency modulation rate differently, and this is made possible by the spread spectrum setting section 143.

Upon receiving image data from the outside, the spread spectrum setting unit 143 resets the modulation frequency and frequency modulation rate stored in the memory 141 according to the pattern of the received image data.

For example, when the received image data is low-tone image data such as a white monochromatic pattern, the modulation frequency and the frequency modulation rate are reset to values lower than a predetermined value. Alternatively, the modulation frequency and the frequency modulation rate can be reset to a value lower than a predetermined value even when the temperature of the system is equal to or higher than a predetermined value.

The spread spectrum setting unit 143 resets the modulation frequency and the frequency modulation rate stored in the memory 141 in accordance with the pattern of the image data and the clock signal modulating unit 142 modulates the modulation frequency stored in the memory 141 and the frequency modulation rate The spectral clock signal (Spectrum CLK) modulated differently according to the pattern of the image data input from the outside is output. The control signal generator 144 generates a control signal using a spectrum clock signal (Spectrum CLK) that is differently modulated.

That is, when the spread spectrum setting unit 143 is vulnerable to a wavy noise according to a pattern of image data input from the outside or a temperature of the system, the spread spectrum setting unit 143 applies the relaxed frequency modulation reference to the clock signal CLK Modulated and outputting a control signal so as to prevent electromagnetic interference (EMI) improvement while preventing a Wavy Noise.

Accordingly, the timing controller 140 according to the present exemplary embodiment generates a control signal using a clock signal CLK input from the outside, and generates a control signal based on a spectral clock signal differently modulated according to a pattern of image data input from the outside (Spectrum CLK), so that different control signals are output according to the pattern of the image data.

The driving timings of the gate driver 120 and the data driver 130 are determined according to control signals output from the timing controller 140. When the gate driver 120 drives the respective gate lines GL The data driver 130 supplies a voltage to the data line DL so that the image is displayed on the display panel 110.

The control signal output from the timing controller 140 is generated using a modulated spectrum clock signal (Spectrum CLK), and the spectrum clock signal (Spectrum CLK) is a signal differentially modulated according to a pattern of image data. Therefore, since the control signal is generated using the spectrum clock signal (Spectrum CLK) modulated differently according to the pattern of the image data, the scan signal outputted by the gate driver 120 is a signal modulated differently according to the pattern of the image data .

Therefore, the display panel 110 can be driven by a scan signal differently modulated according to the pattern of the image data to be displayed.

For example, in the case of displaying general image data, the gate lines GL are formed by a scan signal according to a control signal generated using a spectrum clock signal CLK modulated according to a predetermined modulation frequency and a frequency modulation rate, And the image is displayed.

In the case of displaying the low gray level image data, the modulation frequency and the frequency modulation rate are reset to be low. Therefore, the scan signal according to the control signal generated using the spectrum clock signal (Spectrum CLK) modulated according to the reset modulation frequency and the frequency modulation rate Each of the gate lines GL is driven to display an image.

Accordingly, when the pattern of the displayed image data is the general image data, the display panel 110 is driven according to the first scan signal. If the pattern of the image data is image data weak to the Wavy Noise, 2 scan signal.

That is, a display is driven by a scan signal according to a control signal generated using a spectral clock signal (Spectrum CLK) modulated with different modulation frequencies and frequency modulation rates according to a pattern of image data to be displayed, In the case of the image data pattern weak to the Wavy Noise, since the modulated signal is used according to the low modulation frequency and the low frequency modulation rate, the wobble noise of the scan signal is reduced to prevent recognition as Wavy Noise.

12 and 13 show a process of a spread spectrum signal processing method of the display apparatus 100 according to the present embodiments. FIG. 12 shows a clock signal (CLK) modulation according to a pattern of image data input from the outside And FIG. 13 shows the clock signal (CLK) modulation according to the temperature of the system.

Referring to FIG. 12, the spread spectrum signal processing apparatus receives image data and a clock signal CLK from the outside (S1200).

The pattern of the image data received from the outside is analyzed (S1220), and it is determined whether or not the image data is vulnerable to the Wavy Noise. For example, it is determined whether it corresponds to the low gray level video data (S1240).

If the received image data corresponds to the low gray level image data, the stored modulation frequency and the frequency modulation rate are reset to a value lower than a predetermined value (S1260), and the externally input clock signal CLK) is modulated (S1280).

If the received image data does not correspond to the low gray level image data, the clock signal (CLK) is modulated according to a predetermined modulation frequency and a frequency modulation rate, so that the clock signal (CLK) . Therefore, the shake of the scan signal is reduced by using the spectrum clock signal (Spectrum CLK) which is differently modulated, so that even if the image data pattern is weak to the Wavy noise, the Wavy Noise is not recognized .

Referring to FIG. 13, the spread spectrum signal processing apparatus receives the clock signal CLK from the outside (S1300) and confirms the temperature of the system (S1320).

If the temperature of the system is higher than a preset temperature (S1340), the stored modulation frequency and the frequency modulation rate are reset to a value lower than a predetermined value (S1360).

The image quality can be improved even when the temperature of the system is increased to increase the jitter by modulating the externally inputted clock signal CLK according to the reset modulation frequency and the frequency modulation rate.

According to the embodiments described above, when the spread spectrum signal processing apparatus modulates the clock signal (CLK) received from the outside, it is set differently depending on whether the displayed image data is a pattern vulnerable to Wavy Noise Modulates the clock signal (CLK) using the modulation frequency and the modulation rate, thereby reducing the electromagnetic interference (EMI) through the spread spectrum and preventing the Wavy Noise from being recognized.

In the case of image data that is not susceptible to wavy noise by resetting the modulation frequency and the modulation rate in real time, the clock signal (CLK) is modulated according to the initially set modulation frequency and frequency modulation rate, (EMI) reduction effect.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. The embodiments of the present invention are not intended to limit the scope of the present invention but to limit the scope of the present invention.

100: display device 110: display panel
120: gate driver 130: data driver
140: timing controller 141: memory
142: clock signal modulator 143: spread spectrum setting unit
144: control signal generator 150: spread spectrum integrated circuit
200: pixel (pixel)

Claims

A spread spectrum integrated circuit that receives a clock signal from the outside and modulates the received clock signal according to the stored modulation frequency and frequency modulation rate and outputs a modulated spectrum clock signal; And
And a timing controller for generating a signal for controlling at least one of the gate driver and the data driver using the spectrum clock signal,
The timing controller includes:
A spread spectrum of a display device for resetting a modulation frequency and a frequency modulation rate according to a pattern of input image data and for transmitting a reset modulation frequency and a modulation rate of modulation to the spread spectrum integrated circuit to update a value stored in the spread spectrum integrated circuit; Signal processing device.

The method according to claim 1,
The spread spectrum integrated circuit comprising:
Periodically checking the stored modulation frequency and frequency modulation rate, and modulating the received clock signal based on the stored modulation frequency and frequency modulation rate.

The method according to claim 1,
The timing controller includes:
And resets a predetermined modulation frequency and a frequency modulation ratio to a value lower than a predetermined value according to the pattern of the input image data.

The method of claim 3,
The timing controller includes:
And resets the reconfigured modulation frequency and the frequency modulation rate to an initial value according to a pattern of the input image data after resetting the modulation frequency and the frequency modulation rate.

The method according to claim 1,
The timing controller includes:
A spread spectrum signal processor for a display device that stores a modulation frequency and a frequency modulation rate corresponding to a pattern of the input image data in a lookup table and resets the modulation frequency and the frequency modulation rate according to a value stored in the lookup table, .

The method according to claim 1,
The timing controller includes:
And resetting the modulation frequency and the frequency modulation ratio to a value lower than a predetermined value if the input image data is low gray level image data.

The method according to claim 1,
The timing controller includes:
And resets the modulation frequency and the frequency modulation rate to values lower than a preset value when the temperature of the system is higher than a predetermined temperature.

Receiving a clock signal from the outside;
Modulating the received clock signal according to a modulation frequency and a frequency modulation rate stored in a memory and outputting a modulated spectrum clock signal; And
Generating a control signal using the spectral clock signal,
Wherein the step of outputting the modulated spectral clock signal comprises:
A method for processing a spectrum signal of a display device, comprising: resetting a modulation frequency and a frequency modulation rate stored in the memory according to a pattern of input image data; and modulating the received clock signal according to a reset modulation frequency and a frequency modulation rate.

9. The method of claim 8,
Wherein the step of outputting the modulated spectral clock signal comprises:
And resetting the modulation frequency and the frequency modulation rate stored in the memory to a value lower than a predetermined value if the input image data is low gray level image data.

9. The method of claim 8,
Wherein the step of outputting the modulated spectral clock signal comprises:
And resetting the modulation frequency and the frequency modulation rate stored in the memory to a value lower than a predetermined value in accordance with the temperature of the system.

A display panel including a plurality of pixels arranged in a region where a plurality of gate lines and a plurality of data lines intersect and an area where the gate lines and the data lines intersect;
A gate driver for driving the plurality of gate lines;
A data driver for supplying a data voltage to the plurality of data lines; And
And a timing controller for generating a control signal for controlling driving of the gate driver and the data driver using a clock signal received from the outside,
The timing controller includes:
And modulating the clock signal received from the outside according to a predetermined modulation frequency and a modulation rate of the frequency, generating the control signal using the modulated spectrum clock signal, To generate the control signal.

12. The method of claim 11,
The timing controller includes:
A memory for storing the modulation frequency and the frequency modulation rate;
A clock signal modulator for modulating a clock signal received from the outside according to a modulation frequency and a frequency modulation rate stored in the memory; And
And a spread spectrum setting unit for resetting the modulation frequency and frequency modulation rate stored in the memory according to the pattern of the input image data.

13. The method of claim 12,
Wherein the spread spectrum setting unit comprises:
And to reset the modulation frequency and the frequency modulation rate stored in the memory to a value lower than a predetermined value if the input image data is low gray level image data.