KR100498549B1 - Source Driver Integrated Circuit And Source Driving System using That Circuit Of Liquid Crystal Display Module - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a source driver integrated circuit and a source driving system of an LCD module for improving image quality and reducing component count in an LCD module.

The present invention includes a voltage output unit for driving a source line by receiving a gamma correction voltage and outputting a buffered gamma correction voltage and receiving a corresponding buffering gamma correction voltage and a digital data signal to output a driving voltage. In addition, in the LCD module, a plurality of sources for driving a source line by receiving a gamma correction voltage and outputting a buffered gamma correction voltage and receiving a corresponding buffering gamma correction voltage again and outputting a driving voltage to the LCD panel Characterized in that it comprises a driver integrated circuit, by using one gamma buffer for one particular gamma correction voltage to prevent the driving voltage deviation between the source driver integrated circuit, it is possible to improve the problem of image quality degradation And a gamma buffer having a plurality of gamma buffers Source by incorporating a driver integrated circuit, it is possible to reduce the number of parts of the LCD module.

Description

Source driver integrated circuit and source driving system using that circuit of liquid crystal display module

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display (hereinafter referred to as an LCD). In particular, a source driver integrated circuit and a source of an LCD module for improving image quality and reducing the number of components in an LCD module. It relates to a driving system (Source Driving System).

In general, the LCD receives digital data containing image information processed by a graphic controller in a personal computer (PC), converts the signal into a liquid crystal driving signal in a column driving integrated circuit, and applies the liquid crystal driving signal to a liquid crystal. Device.

Hereinafter, a source driving system of a conventional LCD module will be described.

First, an example of a conventional LCD module will be described with reference to FIG. 1.

1 is a view showing an example of a conventional LCD module.

The conventional LCD module includes a source driving system 100, a source printed circuit board (PCB) 200, a gate driving system 300, a gate PCB 400, and an LCD panel 500. .

The source PCB 200 receives a video signal from a video graphic adapter (VGA) board, converts it into various signals, and transmits the converted signal to the source driving system 100 and the gate driving system 300. And a power supply unit 220 receiving power from the VGA board and supplying power to the source driving system 100, the gate driving system 300, and the timing controller 210, and receiving power from the power supply unit 220. And a gamma correction voltage generator 230 for generating a gamma correction voltage (Vgma) and supplying the gamma correction voltage to the source driving system 100.

The LCD panel 500 includes a source line, a gate line, and a pixel to display a screen, and the source driving system 100 includes the source PCB 200 and the LCD panel. And a plurality of source driver integrated circuits 110-1 to n to drive the source lines of the corresponding LCD panel 500, and the gate driving system 300 includes the It is connected to the gate PCB 400 and the LCD panel 500 and includes a plurality of gate driver integrated circuits 300-1 to m to drive the gate lines of the LCD panel 500.

Hereinafter, the source driver integrated circuit 110 will be described with reference to FIG. 2.

FIG. 2 is a diagram illustrating a conventional source driver integrated circuit in FIG. 1.

The source driver integrated circuit 110 may include a data start signal EIO (Enable Input Output) 1, EIO 2, a polarity control signal POL, a load signal LOAD, a data clock signal DCLK, and a direction signal Lb / R. : Control Block 111, Shift Register 112, Reverse Signal (REV (Reverse) 1, REV2) and Digital Data Signal (D00 ~ D55) that receives Left Bar Right. ) Is a data register 113, a two line latch 114, and a voltage output unit 118 that receive and output the digital data signal.

Hereinafter, the voltage output unit 118 will be described with reference to FIG. 3.

3 is a view illustrating a voltage output unit in FIG. 2.

The voltage output unit 118 includes a gamma buffer unit 117, an output D / A converter 115, and an output driving circuit 116. The gamma buffer unit 117 is provided with a plurality of gamma buffers 117a, 117b, and 117c (three examples in FIG. 3) to receive and buffer the gamma correction voltage from the gamma correction voltage generator 230. And outputs a corresponding buffered gamma correction voltage (Vb-gma), and the output D / A converter 115 receives the buffered gamma correction voltage and divides the resistors (r1 to 63; 63 in FIG. 3). In this case, the digital data signal is converted into an analog data signal according to the switching by receiving a resistor array 115a for outputting the divided gamma voltages V0 to 63 and dividing the gamma voltage. Switch array to convert (Switch Array) (11 5b-1 to n, and the output driving circuit 116 includes a plurality of output buffers 116-1 to n corresponding to the switch array 115b one to one. It is provided with an output driving circuit (Output Driving Circuit) 116 for outputting the driving voltage (OUT1 ~ n) to the LCD panel 500.

Hereinafter, a connection relationship between the gamma correction voltage generator 230 and an example of the conventional source driving system 100 will be described with reference to FIG. 4.

4 is a diagram illustrating a connection relationship between a gamma correction voltage generator and an example of a conventional source driving system in FIG. 1.

As shown in FIG. 4, the gamma correction voltage generator 230 outside the source driving system 100 receives the first and second input voltages Vin1 and Vin2 from the power supply unit 220. Outputs the first, second and third gamma correction voltages Vgam1, Vgam2, and Vgam3 that are voltage-divided according to the provided gamma correction resistors R1, R2, R3, and R4; .

In this case, the first, second and third gamma correction voltages are input to the gamma buffer unit 117 of the source driver integrated circuit 110, respectively. In other words, the first gamma correction voltage may include the first source driver integrated circuit 110-1, the second source driver integrated circuit 110-2,. Input to the first gamma buffer 117a in the gamma buffer unit 117 of the n-th source driver integrated circuit 110-n, and the second gamma correction voltage is first source driver integrated circuit 110-1. ), Second source driver integrated circuit 110-2,... The second gamma correction voltage is input to the second gamma buffer 117b of the gamma buffer unit 117 of the nth source driver integrated circuit 110-n, and the third gamma correction voltage is first source driver integrated circuit 110-1. ), Second source driver integrated circuit 110-2,... And the third gamma buffer 117c in the gamma buffer unit 117 of the nth source driver integrated circuit 110-n.

As described above, in the conventional LCD module, the correction voltage generator 230 generates a gamma correction voltage and is supplied to the plurality of source driver integrated circuits 110 in the source driving system 100 in parallel. In this case, the gamma correction voltage is appropriately adjusted to the values of the gamma correction resistors of the gamma correction voltage generator 230 to match the intrinsic characteristics of the LCD panel 500.

The generated gamma correction voltage is supplied to a plurality of source driver integrated circuits 110 in the source driving system 100, and the buffered gamma correction voltages Vb-gma1, which are output from the gamma buffer unit 117, are output. Vb-gma2, Vb-gma3) are input to the register array 115a, and the register array 115a uses the input buffering gamma correction voltage for the n-bit output D / A converter 115. ⁿ distribution gamma voltages are generated and supplied to the switch array unit 115b in parallel.

Accordingly, each of the plurality of switch arrays 115b-1 to n in the switch array unit 115b is selected from one of 2 ⁿ divided gamma voltages input from the register array 115a according to the received digital data signal. The distribution gamma voltage, that is, the analog data signal is transmitted to the output buffer unit 116, and each of the plurality of output buffers 116-1 to n in the output buffer unit 116 is the selected and transmitted distribution gamma voltage, That is, the driving voltage is output to the LCD panel 500 to drive the source line of the LCD panel 500.

As described above, the reason why the gamma buffers 117a, 117b, and 117c are built in the source driver integrated circuit 110 is because of the gamma correction resistors R1, R2, R3, and R4 of the gamma correction voltage generator 230. This is to prevent the gamma correction voltage from being changed due to the distribution resistor of the resistor array 117 inside the corresponding source driver integrated circuit 110.

That is, in order to prevent the gamma correction voltage generated by the gamma correction voltage generator 230 from being affected by the resistance of the resistor array 115a, the output of the gamma correction voltage generator 230 and the resistor array 115a. Inserts a gamma buffer unit 117 consisting of a plurality of gamma buffers between the inputs of the.

As described above, when the gamma buffer unit 117 is incorporated in each source driver integrated circuit 110, the characteristics of the gamma buffer do not match, that is, the first source driver integrated circuit 110-1. Gamma buffer 117a of the second source driver integrated circuit 110-2,... And the characteristics of the gamma buffer 117a of the n-th source driver integrated circuit 110-n do not match, for example, the gamma buffer 117a of the first source driver integrated circuit 110-1 and the n-th source driver. Even though the gamma buffer 117a of the integrated circuit 110-n receives the same gamma correction voltage from the gamma correction voltage generator 230, there is some deviation between the outputs of the gamma buffer 117a. Due to such a deviation, in the above-described example, the distribution gamma voltages in the first source driver integrated circuit 110-1 are VO, V1, V2,... And V63, while in the nth source driver integrated circuit 110-n, the divided gamma voltages are VO ', V1', V2 ',... V63 'results in a deviation, and a deviation in driving voltage occurs between the respective source driver integrated circuits 110-1 and 110-n, thereby causing a serious deterioration in image quality.

Therefore, another conventional source driving system has been proposed to solve the problem of deterioration in image quality caused by the example of the conventional source driving system 100 described above. Hereinafter, only the differences from the example of the conventional source driving system described above will be mainly described. do.

First, another example of a conventional LCD module will be described with reference to FIG. 5.

5 is a view showing another example of a conventional LCD module.

In the example of the conventional LCD module illustrated in FIG. 1, the gamma buffer unit 117 is provided inside each of the plurality of source driver integrated circuits 110 in the source driving system 100, but the conventional LCD module illustrated in FIG. 5 is provided. In another example, the gamma buffer unit 117 is provided outside each of the plurality of source driving integrated circuits 110.

Hereinafter, the source driver integrated circuit 110 will be described with reference to FIG. 6.

FIG. 6 is a diagram illustrating a conventional source driver integrated circuit in FIG. 5.

Although the source driver integrated circuit 110 for the example of the conventional source driving system 100 shown in FIG. 2 includes a gamma buffer unit 117 in the voltage output unit 118, the conventional source driving system shown in FIG. Source driver integrated circuit 110 for another example of 100 does not have a gamma buffer 117 in voltage output 118.

Hereinafter, the voltage output unit 118 will be described with reference to FIG. 7.

FIG. 7 is a diagram illustrating a voltage output unit in FIG. 6.

The resistor array 115a of the voltage output unit 118 for the example of the conventional source driving system 100 shown in FIG. 3 is buffered gamma from the gamma buffer unit 117 provided inside the voltage output unit 118. Although the correction voltage is input, the resistor array 115a at the voltage output unit 118 for another example of the conventional source driving system 110 shown in FIG. 7 is provided with a gamma buffer provided outside the voltage output unit 118. The buffering gamma correction voltage is input from the unit 117.

Hereinafter, a connection relationship between the gamma correction voltage generator 230 and another example of the conventional source driving system 100 will be described with reference to FIG. 8.

FIG. 8 is a diagram illustrating a connection relationship between the gamma correction voltage generator 230 and another example of the conventional source driving system 100 in FIG. 5.

When comparing only the difference between the gamma correction voltage generator 230 illustrated in FIG. 4 and an example of the conventional source driving system 100, only the difference is explained. The gamma correction voltage outside the source driving system 100 is described. The gamma correction voltages Vgma1, Vgma2, and Vgma3 output from the generator 230 are input to the gamma buffer unit 117 of the source driver integrated circuit 110, respectively, and are buffered and output from the corresponding gamma buffer unit 117. The buffering gamma correction voltages Vb-gma1, Vb-gma2, and Vb-gma3 are input to the register array 115a of the source driver integrated circuit 110, respectively. In other words, the first, second and third buffering gamma correction voltages may include the first source driver integrated circuit 110-1, the second source driver integrated circuit 110-2,. Are input to the register array 115a in the output D / A converter 115 of the n-th source driver integrated circuit 110-n, respectively.

As shown in FIGS. 1, 2, 3, and 4, in the example of the conventional source driving system 100 described above, a gamma buffer unit 117 having a plurality of gamma buffers may be provided inside the plurality of source driver integrated circuits 110. FIG. In order to remove the output deviation between the source driver integrated circuit 110, that is, the driving voltage variation due to the characteristic mismatch of the respective gamma buffers, respectively, as described above with reference to FIGS. 5, 6, 7, and 8 In another example of the conventional source driving system 100, the gamma buffer unit 117 including the plurality of gamma buffers is configured as a separate component, and each of the source driver integrated circuit 110 is provided outside the source driver integrated circuit 110, thereby providing a conventional image quality. The degradation problem was improved. That is, since the characteristic mismatch between the gamma buffers is not affected, for example, the divided gamma voltages in the first source driver integrated circuit 110-1 are VO, V1, V2,... , V63, the distribution gamma voltage in the nth source driver integrated circuit 110-n is also represented by VO, V1, V2,... , V63 does not occur, and there is no variation in driving voltage between the respective source driver integrated circuits 110-1 and 100-n, and therefore, image quality deterioration does not occur.

However, as the separate parts are used, the assembly process increases, the defect rate increases, and the cost increases.

In order to solve the problems described above, an object of the present invention is to improve the image quality of the LCD module. In addition, another object of the present invention is to reduce the number of components of the LCD module.

In order to solve the above object, the source driver integrated circuit of the LCD module of the present invention, the LCD module including a voltage output unit having an output driver circuit for outputting a drive voltage for driving the source line of the LCD panel In the source driver integrated circuit, the voltage output unit buffers a gamma correction voltage input from one side of the gamma correction voltage generator disposed outside the source driver integrated circuit to output a buffered gamma correction voltage to the outside of the source driver integrated circuit. A gamma buffer unit having a plurality of gamma buffers; The buffering gamma correction voltage is input from the outside of the source driver integrated circuit, and the buffering gamma correction voltage corresponding to the gamma correction voltage input from the other side of the gamma correction voltage generator is further equal to that of the source driver integrated circuit. An output D / A converter which converts a digital data signal input from a data register of the source driver integrated circuit into an analog data signal by inputting from a source driver integrated circuit; And an output driving circuit converting the analog data signal inputted from the output D / A converter into a driving voltage for driving the source line of the LCD panel and outputting the same.

Preferably, the output D / A converter is configured to divide the buffering gamma correction voltage input from the outside of the source driver integrated circuit and the buffering gamma correction voltage input from the another source driver integrated circuit by a divider resistor. A resistor array outputting a distribution gamma voltage; And a switch array configured to convert the digital data signal into the analog data signal and output the analog data signal when the divided gamma voltage is input and switched. The output driving circuit includes a plurality of output buffers that correspond one-to-one with the switch array. The analog data signal inputted from the switch array may be converted into the driving voltage and output. The source driving system using the source driver integrated circuit of the LCD module of the present invention may include a first source driver integrated with the same structure. In the source drive system of the LCD module including a circuit and a second source driver integrated circuit, The first source driver integrated circuit is a gamma input from one side of the gamma correction voltage generation unit disposed outside the first source driver integrated circuit Buffer by buffering the compensation voltage A gamma buffer unit having a plurality of gamma buffers to output a gamma correction voltage to the outside of the first source driver integrated circuit; The buffering gamma correction voltage is input from the outside of the first source driver integrated circuit, and the buffering gamma correction voltage corresponding to the gamma correction voltage input from the other side of the gamma correction voltage generator is input from the second source driver integrated circuit. An output D / A converter for converting and outputting a digital data signal input from a data register of the first source driver integrated circuit into an analog data signal by an input; And an output driving circuit for converting an analog data signal input from the output D / A converter into a driving voltage for driving the source line of the LCD panel, and outputting the converted driving voltage. The second source driver integrated circuit includes the gamma. A plurality of buffering gamma correction voltages input from the other side of the correction voltage generation unit and outputting the corresponding buffered gamma correction voltage to the output D / A converter of the first source driver integrated circuit from outside the second source driver integrated circuit. A gamma buffer unit having a gamma buffer; A buffering gamma correction voltage is input from the first source driver integrated circuit, and the corresponding buffering gamma correction voltage is input from outside of the second source driver integrated circuit, thereby inputting from a data register of the second source driver integrated circuit. An output D / A converter for converting the digital data signal to an analog data signal and outputting the analog data signal; And an output driving circuit converting the analog data signal inputted from the output D / A converter into a driving voltage for driving the source line of the LCD panel and outputting the same.

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Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 9 is a view showing an LCD module to which the present invention is applied, FIG. 10 is a view showing a source driver integrated circuit according to an embodiment of the present invention in FIG. 9, and FIG. 11 is a view showing a voltage output unit in FIG. 10. FIG. 12 is a diagram illustrating a connection relationship between a gamma correction voltage generator and a source driving system according to an exemplary embodiment of the present invention.

As shown in FIG. 9, the LCD module to which the present invention is applied consists of a source driving system 100, a source PCB 200, a gate driving system 300, a gate PCB 400, and an LCD panel 500. .

The source PCB 200 includes a timing controller 210, a power supply unit 220, and a gamma correction voltage generator 230. The timing controller 210 receives an image signal from a VGA board, converts the image signal into various signals, and transmits the image signal to the source driving system 100 and the gate driving system 300. The power supply unit 220 receives power from the VGA board and supplies the power to the source driving system 100, the gate driving system 300, and the timing controller 210. The gamma correction voltage generator 230 receives power from the power supply unit 220, generates a gamma correction voltage, and supplies the gamma correction voltage to the source driving system 100.

The LCD panel 500 includes a source line, a gate line, and a pixel to display a screen. The source driving system 100 is connected to the source PCB 200 and the LCD panel 500 and includes a plurality of source driver integrated circuits 110-1 to n to drive source lines of the corresponding LCD panel 500. do. The gate driving system 300 is connected to the gate PCB 400 and the LCD panel 500 and includes a plurality of gate driver integrated circuits 300-1 to m to drive the gate line of the LCD panel 500. do.

As shown in FIG. 12, the source driving system 100 receives a gamma correction voltage Vgma from the LCD module, outputs a buffered gamma correction voltage Vb-gma, and receives the buffering gamma correction voltage again. It includes a plurality of source driver integrated circuit 110 for outputting the driving voltage to the LCD panel 500 to drive the source line.

As shown in FIG. 10, the source driver integrated circuit 110 includes a controller 111, a shift register 112, a data register 113, a two line latch 114, and a voltage output unit 118. The control unit 111 controls the data start signals EIO1 and EIO2, the polarity control signal POL, the load signal LOAD, the data clock signal DCLK, and the direction signal Lb / R (Left bar Right). In response to the input, the entire data register 113 receives reverse signals REV1 and REV2 and digital data signals D00 to D55, and the two line latch 114 receives and outputs the digital data signals. The voltage output unit 118 receives the gamma correction voltage to output a buffered gamma correction voltage, receives the corresponding buffering gamma correction voltage and the digital data signal, and outputs a driving voltage to drive a source line.

Hereinafter, as shown in FIG. 11, the voltage output unit 118 includes a gamma buffer unit 117, an output D / A converter 115, and an output driving circuit 116. The gamma buffer unit 117 includes a plurality of gamma buffers 117a and 117b (two cases in FIG. 11), and thus the gamma correction voltages Vgma1, Vgma2, and Vgma3 from the gamma correction voltage generator 230. ) Is buffered and outputs the buffered gamma correction voltages Vb-gma1, Vb-gma2, and Vb-gma3 to the outside of the source driver integrated circuit 110.

The output D / A converter 115 receives the buffering gamma correction voltage from the outside of the source driver integrated circuit 110 according to the division resistors r1 to 63 (63 cases in FIGS. 11 and 12). The switch array unit 115b-1-n converting the digital data signal into an analog data signal in response to a switching by receiving a resistor array 115a for outputting the divided gamma voltages V0 to 63 by voltage division. ).

The output driving circuit 116 includes a plurality of output buffers 116-1 to n corresponding to the switch array 115b to receive the analog data signal to receive driving voltages OUT1 to n from the LCD panel. Output as 500.

Hereinafter, the connection relationship between the gamma correction voltage generator 230 and the source driving system 100 will be described with reference to FIG. 12. In FIG. 12, a connection relationship between the source driver integrated circuit 110-1 and the source driver integrated circuit 110-n is taken as an example.

The gamma correction voltage generator 230, which is external to the source driving system 100, receives the first and second input voltages Vin1 and Vin2 from the power supply unit 220, and includes a gamma correction resistor R1, which is provided therein. The first, second, and third gamma correction voltages Vgam1, Vgam2, and Vgam3 that are voltage-divided according to R2, R3, and R4;

In this case, the first, second and third gamma correction voltages are input to the gamma buffer unit 117 of the source driver integrated circuit 110, respectively. That is, the first gamma correction voltage is input to the first gamma buffer 117a in the gamma buffer unit (hereinafter referred to as the nth gamma buffer unit) 117 of the nth source driver integrated circuit 110-n. The second gamma correction voltage is input to the first gamma buffer 117a in the gamma buffer unit 117 (hereinafter referred to as a first gamma buffer unit) of the first source driver integrated circuit 110-1. The three gamma correction voltage is input to the second gamma buffer 117b in the first gamma buffer unit 117 of the first source driver integrated circuit 110-1.

The first gamma buffer 117a of the n-th gamma buffer unit 117 that receives the first gamma correction voltage Vgma1 outputs a first buffering gamma correction voltage Vb-gma1 to output the first gamma correction voltage Vgmag. A buffering gamma correction voltage is input to the register array 115a of the first source driver integrated circuit 110-1 and the register array 115a of the nth source driver integrated circuit 110-n, and the second gamma The first gamma buffer 117a of the first gamma buffer unit 117 receiving the correction voltage Vgma2 outputs a second buffering gamma correction voltage Vb-gma2 to output the corresponding second buffering gamma correction voltage. The register array 115a of the first source driver integrated circuit 110-1 and the register array 115a of the nth source driver integrated circuit 110-n are input to the third gamma correction voltage Vgma3. The second gamma buffer 117b of the first gamma buffer unit 117 received is third buffered. The gamma correction voltage Vb-gma3 is output to output the corresponding third buffered gamma correction voltage to the register array 115a of the first source driver integrated circuit 110-1 and the nth source driver integrated circuit 110-. input to the register array 115a of n).

Accordingly, each register array 115a generates 2 ⁿ divided gamma voltages in the case of the n-bit output D / A converter 115 by using the input gamma correction voltage to the switch array unit 115b. Supply in parallel. In this case, in the above example, the distribution gamma voltages V0 to 63 output from the first source driver integrated circuit 110-1 and the distribution gamma voltages V0 output from the nth source driver integrated circuit 110-n. 63 is the same.

In addition, each of the plurality of switch arrays 115b-1 to n in the switch array unit 115b is selected from one of 2 ⁿ divided gamma voltages input from the register array 115a according to the received digital data signal. The distribution gamma voltage, that is, the analog data signal, is transferred to the output buffer unit 116.

Accordingly, each of the plurality of output buffers 116-1 to n in the output buffer unit 116 outputs the selected and transmitted distribution gamma voltage, that is, a driving voltage to the LCD panel 500, so as to output the corresponding LCD panel 500. Drive the source line.

In the example of the conventional source driving system shown in Figs. 1, 2, 3 and 4, when the gamma buffer unit is embedded in each source driver integrated circuit, each gamma buffer for each of a plurality of source driver integrated circuits in one gamma correction voltage. Since the characteristics of the respective gamma buffers do not coincide with each other and the same gamma correction voltage is input from the gamma correction voltage generator, some deviation occurs between the outputs of the respective gamma buffers. There is a problem in that the driving voltage is different from each other, which causes a serious degradation in image quality. However, in the source driving system of the present invention, the driving voltage between the source driver integrated circuits using one gamma buffer for one specific gamma correction voltage is used. In order to improve image quality degradation problem, Can.

In addition, the plurality of gamma in another example of the conventional source driving system shown in FIGS. 5, 6, 7, and 8 is proposed to eliminate the problem of deterioration in image quality due to the driving voltage deviation in the example of the conventional source driving system described above. By configuring the gamma buffer unit having a buffer as a separate component, and each of the plurality of source driver integrated circuits outside, the problem of deterioration of the conventional image quality is improved, while the use of separate components increases the assembly process and the defective rate. Increasing costs have increased, but in the source driving system of the present invention, by embedding a gamma buffer unit having a plurality of gamma buffers in a source driver integrated circuit, the number of parts of the LCD module can be reduced.

In addition, the embodiment according to the present invention is not limited to the above-mentioned, and can be implemented by various alternatives, modifications, and changes within the scope apparent to those skilled in the art.

As described above, the present invention can solve the problem of deterioration in image quality by using one gamma buffer for one specific gamma correction voltage so as not to cause driving voltage variations between the source driver integrated circuits, and also provides a plurality of gamma buffers. By embedding the gamma buffer unit having the integrated circuit into the source driver integrated circuit, the number of components of the LCD module can be reduced.

1 is a view showing an example of a conventional LCD module.

FIG. 2 shows a conventional source driver integrated circuit in FIG. 1; FIG.

3 is a view showing a voltage output unit in FIG.

4 is a diagram illustrating a connection relationship between a gamma correction voltage generator and an example of a conventional source driving system in FIG. 1.

5 is a view showing another example of a conventional LCD module.

FIG. 6 shows a conventional source driver integrated circuit in FIG. 5; FIG.

7 is a view showing a voltage output unit in FIG.

FIG. 8 is a diagram illustrating a connection relationship between a gamma correction voltage generator and another example of a conventional source driving system in FIG. 5. FIG.

9 is a view showing an LCD module to which the present invention is applied.

10 illustrates a source driver integrated circuit in accordance with an embodiment of the present invention in FIG.

FIG. 11 is a view illustrating a voltage output unit in FIG. 10. FIG.

FIG. 12 is a diagram illustrating a connection relationship between a gamma correction voltage generator and a source driving system according to an exemplary embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100: source driving system 110: source driver integrated circuit

115: output D / A converter 115a: resistor array

115b: switch array unit 116: output drive circuit

117: gamma buffer

Claims (3)

In the source driver integrated circuit of an LCD module comprising a voltage output unit having an output driver circuit for outputting a driving voltage for driving a source line of the LCD panel, The voltage output unit, A gamma buffer unit having a plurality of gamma buffers configured to buffer a gamma correction voltage input from one side of the gamma correction voltage generator disposed outside the source driver integrated circuit and output a buffered gamma correction voltage to the outside of the source driver integrated circuit. ; The buffering gamma correction voltage is input from the outside of the source driver integrated circuit, and the buffering gamma correction voltage corresponding to the gamma correction voltage input from the other side of the gamma correction voltage generator is further equal to that of the source driver integrated circuit. An output D / A converter which converts a digital data signal input from a data register of the source driver integrated circuit into an analog data signal by inputting from a source driver integrated circuit; And And an output driving circuit converting the analog data signal inputted from the output D / A converter into a driving voltage for driving the source line of the LCD panel and outputting the converted driving voltage. The method of claim 1, The output D / A converter, A resistor array configured to output a divided gamma voltage by voltage-dividing a buffering gamma correction voltage input from the outside of the source driver integrated circuit and a buffering gamma correction voltage input from the another source driver integrated circuit by a divider resistor; And And a switch array configured to convert the digital data signal into the analog data signal and output the converted data by switching the divided gamma voltage. The output drive circuit, And a plurality of output buffers corresponding to the switch array and converting the analog data signals inputted from the switch array into the driving voltage and outputting the converted driving voltages. In the source drive system of the LCD module including the first source driver integrated circuit, the second source driver integrated circuit having the same structure, The first source driver integrated circuit, A plurality of gamma buffers configured to buffer a gamma correction voltage input from one side of the gamma correction voltage generator disposed outside the first source driver integrated circuit to output a buffered gamma correction voltage to the outside of the first source driver integrated circuit A gamma buffer portion; The buffering gamma correction voltage is input from the outside of the first source driver integrated circuit, and the buffering gamma correction voltage corresponding to the gamma correction voltage input from the other side of the gamma correction voltage generator is input from the second source driver integrated circuit. An output D / A converter for converting and outputting a digital data signal input from a data register of the first source driver integrated circuit into an analog data signal by an input; And An output driving circuit converting the analog data signal inputted from the output D / A converter into a driving voltage for driving the source line of the LCD panel and outputting the driving voltage; The second source driver integrated circuit, Buffering the gamma correction voltage input from the other side of the gamma correction voltage generator to output the corresponding buffered gamma correction voltage to the output D / A converter of the first source driver integrated circuit from outside the second source driver integrated circuit; A gamma buffer unit having a plurality of gamma buffers; A buffering gamma correction voltage is input from the first source driver integrated circuit, and the corresponding buffering gamma correction voltage is input from outside of the second source driver integrated circuit, thereby inputting from a data register of the second source driver integrated circuit. An output D / A converter for converting the digital data signal to an analog data signal and outputting the analog data signal; And And an output driver circuit for converting the analog data signal inputted from the output D / A converter into a driving voltage for driving the source line of the LCD panel, and outputting the output voltage. Source driven system.