KR100469348B1 - Data operating circuit for liquid crystal display device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data driving circuit of a liquid crystal display device capable of driving various delta type liquid crystal panels. The present invention relates to a liquid crystal panel and a gate for sequentially applying a driving voltage to scan lines and signal lines of the liquid crystal panel. A liquid crystal display device comprising a driving circuit and a data driving circuit, comprising: a shift register unit for generating a latch enable clock; a first latch unit for sampling and latching a digital image signal for each data line; A second latch unit for receiving and latching sampled data latched to the latch unit, a digital / analog converter for converting the sampled data into analog data, and a multiplexer unit for adjusting a pixel arrangement of the converted analog data It characterized in that it comprises a configured data driving circuit.

Description

Data driving circuit of liquid crystal display device {DATA OPERATING CIRCUIT FOR LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a display device, and more particularly, to a data driving circuit of a liquid crystal display device.

In general, a liquid crystal display device is formed by arranging two substrates on which electric field generating electrodes are formed so that the surfaces on which the two electrodes are formed face each other, injecting a liquid crystal material between the two substrates, and applying no voltage to the two electrodes. By moving the liquid crystal molecules by an electric field, the device expresses an image by the transmittance of light that varies accordingly.

A liquid crystal display can be formed in various forms. Currently, an active matrix liquid crystal display (AM-LCD) having a thin film transistor and pixel electrodes connected to the thin film transistor in a matrix manner has excellent resolution and video performance. It is most noticed.

Such a liquid crystal display may be classified into a liquid crystal panel unit and a driver unit.

First, the liquid crystal panel unit includes a lower glass substrate on which pixel electrodes and thin film transistors are arranged in a matrix, an upper glass substrate on which a common electrode and a color filter layer are formed, and a liquid crystal layer filled between the upper and lower glass substrates.

In addition, the driving unit processes an image signal input from the outside and outputs a composite synchronization signal, and receives a composite synchronization signal output from the image signal processor, separates and outputs a horizontal synchronization signal and a vertical synchronization signal, and selects a mode. A timing controller for controlling timing in accordance with a signal, a data driving circuit for supplying a signal voltage to a data line of the liquid crystal panel by an output signal of the timing controller, and a gate for sequentially applying a driving voltage to a scanning line of the liquid crystal panel; It consists of a driving circuit.

FIG. 1 shows a brief configuration of the above-described liquid crystal display device, which is composed of a liquid crystal panel 11, a gate driving circuit 12, a data driving circuit 13, and a gamma reference voltage generator 14. As shown in FIG.

The liquid crystal panel 11 is configured such that a plurality of gate lines are arranged in one direction at regular intervals, and a plurality of data lines are arranged in a direction perpendicular to the gate line with a predetermined interval to form a matrix pixel area. .

The gate driving circuit 12 outputs a pulse signal that sequentially scans pixels of the liquid crystal panel by one column.

The data driving circuit 13 generates a liquid crystal driving voltage by performing digital / analog conversion on the reference voltage output from the gamma reference voltage generator 14 based on the signals of R, B, and G, and generates the liquid crystal. A driving voltage is applied to the data line of the liquid crystal panel 10 every scanning. The gamma reference voltage generator generates a reference voltage for generating a liquid crystal driving voltage.

Here, the data driving circuit 13 will be described in more detail as follows.

2 is a block diagram of the data driving circuit 13.

The shift register section 21, the sampling latch section 22, the holding latch section 23, the digital / analog converting section 24, and the output buffer section 25 are provided.

First, the shift register unit 21 shifts the horizontal synchronizing signal pulse HSYNC by the data pulse clock HCLK to output a latch enable clock to the sampling latch unit 22.

Subsequently, the sampling latch unit 22 samples and latches the digital R, G, and B image data for each data line according to the latch enable clock output from the shift register unit 21.

Subsequently, the holding latch unit 23 simultaneously receives and latches R, G, and B data latched by the sampling latch unit 22 by a load signal LD.

Subsequently, the digital / analog converter 24 converts the digital R, G, and B data stored in the holding latch unit 23 into analog R, G, and B data according to the reference voltage of the gamma reference voltage generator 14. .

The output buffer unit 25 amplifies the current of the signal corresponding to the R, G, and B data converted into the analog signal and outputs the current to the data line of the panel.

The data driving circuit 13 configured as described above converts the digital R, G, and B data into analog R, G, and B data after sample & holding during one horizontal period, and amplifies and outputs the current. If the holding latch unit 23 holds R, G, and B data corresponding to the nth data line, the sampling latch unit 22 samples R, G, and B data corresponding to the n + 1th data line. Done.

However, the data driving circuit of the conventional liquid crystal display has the following problems.

The analog R, G, and B data, which are the liquid crystal driving voltages applied to the data lines, are applied to the R, G, and B pixel electrodes having a stripe structure, as shown in FIG. 3. That is, in the data driver 13 operating in line units in order to operate the liquid crystal panel 10, driving cannot be performed in the delta type panel of the pixel array form.

Accordingly, in order to drive the delta type panel, a driving circuit for changing the order of the R, G, and B signals is required.

Accordingly, the present invention has been made to solve the above problems, and provides a data driving circuit of a liquid crystal display device capable of driving even in a stripe type or delta type liquid crystal panel using a multiplexer inside the data driving circuit. For that purpose.

1 is a block diagram for explaining a conventional liquid crystal display device.

2 is a block diagram of a conventional data driving circuit.

3 is a pixel array structure diagram of a conventional liquid crystal panel.

4 is a block diagram illustrating a data driving circuit of a liquid crystal display according to an exemplary embodiment of the present invention.

5 is a diagram illustrating an internal structure of the multiplexer of FIG. 4.

Explanation of symbols on the main parts of the drawings

101: shift register section 102: first latch section

103: second latch unit 104: digital / analog converter

105: buffer section 106: multiplexer section

The data driving circuit of the liquid crystal display device of the present invention for achieving the above object is a liquid crystal display including a liquid crystal panel, a gate driving circuit and a data driving circuit for sequentially applying a driving voltage to the scan line and the signal line of the liquid crystal panel. An apparatus comprising: a shift register for generating a latch enable clock, a first latch for sampling and latching a digital video signal for each data line, and receiving sampled data latched in the first latch And a data driving circuit including a second latching unit for latching, a digital / analog converting unit for converting the sampled data into analog data, and a multiplexer unit for adjusting a pixel arrangement of the converted analog data. .

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

4 is a block diagram illustrating a data driving circuit of a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 5 is an internal structure diagram of the multiplexer of FIG. 4.

The present invention provides a liquid crystal display device having the same structure as described above, and in particular, provides a data driving circuit which can freely adjust the stripe type or the delta type pixel arrangement by changing the data driving circuit. .

First, as shown in FIG. 4, the data driving circuit 100 according to the exemplary embodiment of the present invention may include a shift register unit 101, a first latch unit 102, a second latch unit 103, The digital / analog converter 104, the output buffer 105, and the multiplexer 106 are comprised.

The shift register unit 101 shifts the horizontal synchronizing signal pulse HSYNC by the data pulse clock HCLK, and outputs a latch enable clock to the first latch unit 102.

Subsequently, the first latch unit 102 samples and latches digital R, G, and B image data for each data line according to the latch enable clock output from the shift register unit 101.

Subsequently, the second latch unit 103 simultaneously receives and latches R, G, and B data latched by the first latch unit 102 by a load signal LD.

Subsequently, the digital / analog converter 104 converts the digital R, G, and B data stored in the second latch unit 103 into analog R, G, and B data according to a reference voltage of a gamma reference voltage generator (not shown). Convert.

Subsequently, the buffer unit 105 amplifies the current of the signal corresponding to the R, G, and B data converted into the analog signal and outputs the current to the data line of the panel.

Next, the multiplexer 106 adjusts the pixel arrangement of the converted analog data. That is, the multiplexer 106 applies an analog data signal in a pixel array of stripe type and delta type.

The multiplexer 106 is controlled by an external controller (not shown) by a control signal MUX_Ctrl [1: 0] of a 2-bit signal of ground voltage and power supply voltage, and may be configured as an analog or digital multiplexer.

The multiplexer unit 106 of the data driving circuit of the liquid crystal display having the above structure will be described in more detail as follows.

As shown in FIG. 5, analog data signals of R, G, and B are arranged according to pixel arrangements corresponding to when the external control signal MUX_Ctrl [1: 0] is 00, 01, and 10. Is sent to the data line.

That is, when the external control signal MUX_Ctrl [1: 0] is 00, R, G, B, R, G, B... Signals corresponding to the data lines are sequentially transmitted. When the external control signal MUX_Ctrl [1: 0] is 01, B, R, G, B, R, G... Are transmitted to multiple data lines in order, and when the external control signal (MUX_Ctrl [1: 0]) is 10, G, B, R, G, B, R... It is sent to multiple data lines in order.

Accordingly, by controlling the external control signal MUX_Ctrl [1: 0], a delta type liquid crystal panel of various shapes can be driven.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

The data driving circuit of the liquid crystal display device of the present invention described above has the following effects.

By providing the multiplexer unit 106 by an external control signal in the data driving circuit for driving the liquid crystal panel, various delta type liquid crystal panels can be driven.

As a result, delta array driving can be simplified, and a separate driving circuit for changing the order of the R, G, and B signals is not required in order to drive the conventional delta type panel, thereby reducing the cost.

Claims (5)

A liquid crystal display device comprising a liquid crystal panel, a gate driving circuit and a data driving circuit which sequentially apply driving voltages to scan lines and signal lines of the liquid crystal panel. A shift register section for shifting the horizontal synchronizing signal pulse by the data pulse clock to generate a latch enable clock; A first latch unit for sampling and latching a digital video signal for each data line according to a latch enable clock output from the shift register unit; A second latch unit configured to receive and latch sampled data latched in the first latch unit; A digital / analog converter for converting the sampled data stored in the second latch unit into analog data; A buffer unit for amplifying and outputting sampled data converted into analog signals by the digital / analog converter; It is configured at the output of the buffer unit, and is controlled by a 2-bit signal of the ground voltage and the power supply voltage externally to adjust the pixel array of the analog data converted by the digital / analog converter to convert the data into a stripe type and delta type pixel array. And a data driving circuit comprising a multiplexer section for outputting a signal. The method of claim 1, And a buffer unit for amplifying the current of the analog data signal and outputting the amplified current to the data line of the panel. The method of claim 1, And a data signal is applied to the stripe type and the delta type pixel array by the multiplexer. The method of claim 1, And the multiplexer part is externally adjusted by a 2-bit signal of ground voltage and power supply voltage. The method of claim 1, And the multiplexer portion is any one of an analog and digital multiplexer portion.