TW201939121A - Liquid crystal display control device - Google Patents

Abstract

A liquid crystal display control device includes a plurality of scan lines, a plurality of external data lines, a plurality of switching elements, and a plurality of pixel units. Each of the externaldata lines transmits a data signal, and each of the external data lines is connected with three sub data lines; each of the sub data lines is connected with a switching element to use the corresponding sub data lines to transmit the data signals by sequentially controlling each switching element to turn on. Then, the pixel units can sequentially receive the data signals and drive thin film transistors in the pixel units to control pixel capacitors to charge and discharge to a desired voltage level. The liquid crystal display control device can reduce the number of external pins of source wafers significantly, and can effectively lower the wafer fabrication cost.

Description

LCD display control device

The invention relates to a control device for a liquid crystal display panel, in particular to a data signal transmitted by an external data line, which can be transmitted sequentially through a connected sub-data line to control the corresponding pixel electrode, thereby reducing the source electrode. Liquid crystal display control device for the number of external output pins of the chip.

With the development of Liquid Crystal Display (LCD) technology, the liquid crystal display device has gradually developed into a display technology that currently replaces the traditional cathode ray tube (CRT), and has been widely used. In various electronic products. Generally speaking, in a traditional active matrix liquid crystal display (LCD), the single-gate circuit architecture is as shown in FIG. 1. Each pixel electrode 10 has a thin film transistor (TFT). The gate is connected to the scanning line 12 in the horizontal direction, the source is connected to the data line 14 in the vertical direction, the drain is connected to the pixel electrode, and the thin film transistors in adjacent rows have their own connected data lines 14. To put it simply, it is common practice to use matrix-type liquid crystal display technology to control the driving of a pixel electrode 10 by using a data line 14 and a corresponding scanning line 12.

Furthermore, on the same scanning line 12 in the horizontal direction, the gates of all thin film transistors are connected on the same scanning line, so when a voltage is applied, the operation of these thin film transistors will be linked. That is to say, if a sufficiently large positive voltage is applied to a certain scanning line 12, all the thin film transistors on this scanning line will be turned on (On). In this case, when the thin film electricity After the crystal is turned on, the pixel electrode on the scanning line 12 is connected to the vertical data line 14 and the corresponding video signal is sent through the vertical data line 14 to charge the pixel electrode to the desired location. The voltage level controls the grayscale brightness of the pixel electrode 10 by this action.

After that, a sufficiently large negative voltage is applied and the thin film transistor is turned off until the signal is written again next time, so that the charge can be stored on the liquid crystal capacitor. At this time, the next horizontal scanning line 12 is started to send the corresponding video signal, so that the video data of the entire screen is sequentially written, and then the signal is rewritten from the first one, which is commonly used in practice. LCD panel driving method.

However, it is worth noting that the above-mentioned single-gate circuit architecture, as shown in Figure 1, is a data line with a corresponding scan line to control a pixel electrode drive, which is a one-to-one driving method. When there are a large number of pixel electrodes on the panel, it means that the number of data lines and scanning lines will increase sharply. Because when the number of data lines is too large, the cost of consuming it on the source chip will be quite high. This phenomenon is not welcomed by today's designers. Therefore, the inventor feels that the above mentioned defects can be improved, and based For many years, I have engaged in related experience in this area, carefully observed and researched it, and combined with the application of science, I have proposed a novel design that effectively improves the above-mentioned shortcomings. The manner will be detailed below.

In order to solve the problems existing in the conventional technology, one object of the present invention is to provide a liquid crystal display control device, which can sequentially transmit data signals by using three sub data lines, and simultaneously design a pixel unit corresponding to each sub data line. The system includes at least two pixel electrodes, so that one external data line can control the output of six pixel electrodes correspondingly, thereby reducing the use of the number of external pins of the source chip.

In view of the above, the present invention discloses a liquid crystal display control device, which includes a plurality of scanning lines, a plurality of external data lines, a plurality of switching elements, and a plurality of pixel units. Among them, each scanning line transmits a scanning signal, each external data line transmits a data signal, and each external data line is respectively connected to three sub-data lines to selectively use the sub-data lines to transmit data signals. . In addition, each sub-data line is connected with a switching element, and each switching element is connected in parallel with each other, and each of the switching elements is controlled to be sequentially turned on to transmit the data signal using a corresponding sub-data line. The pixel unit is connected between two adjacent scanning lines and a sub data line, and each pixel unit includes at least two thin film transistors and corresponding at least two pixel capacitors. The present invention is controlled by When each switching element is sequentially turned on, each pixel unit sequentially receives the data signal, and then the thin film transistors are controlled to control the pixel capacitors to be selectively charged or discharged to a desired level. Voltage level.

According to an embodiment of the present invention, the liquid crystal display control device further includes at least one gate chip connected to the scan lines, wherein the gate chip is used to generate the scan signals and transmit each scan line using each scan line. Scan the signal.

According to an embodiment of the present invention, the liquid crystal display control device further includes at least one source chip connected to the external data lines, wherein the source chip is used to generate the data signals and transmit each data by using each data line. Signal.

In addition, the liquid crystal display control device disclosed in the present invention may further include at least one shunt connected to the switching elements and used to generate a plurality of shunt signals, whereby the present invention can utilize each shunt Each switching element corresponding to the signal control turns on sequentially. In one embodiment, the switching element is selected from a metal-oxide-semiconductor field-effect transistor (MOSFET).

Furthermore, the thin film transistor systems in each pixel unit include at least a first thin film transistor and a second thin film transistor. The pixel capacitors include at least a first capacitor and a second capacitor. Capacitor, wherein the first thin film transistor and the second thin film transistor system respectively connect the first capacitor and the second capacitor to control the first capacitor and the second capacitor through the first thin film transistor and the second thin film transistor respectively when the switching element is turned on. Charge and discharge of the second capacitor.

In general, during the charging and discharging of the pixel capacitor, the scanning signal is used to control the switching state of the first thin film transistor and the second thin film transistor. When the first thin film transistor and the second thin film transistor are turned on, The data signal is read so that the first thin film transistor and the second thin film transistor can control the charge and discharge of the first capacitor and the second capacitor according to the data signal.

For example, when the pixel unit receives a data signal, both the first thin film transistor and the second thin film transistor system are turned on at this time to charge the first capacitor and the second capacitor at the same time. In an embodiment, if the voltage level required for the first capacitor is higher than the second capacitor, the second thin film transistor system first completes charging the second capacitor, and then turns off the second thin film transistor, and the first capacitor It continues to charge to the required voltage level. In another embodiment, if the voltage level required for the second capacitor is higher than the first capacitor, the second thin-film transistor system first completes charging the second capacitor, and then turns off the second thin-film transistor, and the first The capacitor is discharged to the required voltage level.

With this innovation and improvement, the liquid crystal display control device disclosed in the present invention is designed to be connected to a plurality of sub data lines by designing an external data line, and controls whether the sub data line transmits a data signal with an appropriate switching element. By controlling the switching element, Sequentially open the data signal, so that data signals can be transmitted through each sub-data line in order to achieve the purpose of sequential stepwise control.

In addition, the present invention designs that each pixel unit includes at least two thin film transistors and corresponding at least two pixel capacitors, wherein each thin film transistor controls the corresponding one pixel capacitor for charging and discharging, which can be regarded as a group Pixel electrodes. Therefore, each pixel unit of the present invention includes at least two groups of pixel electrodes, and in a manner that each pixel unit is controlled by a sub-data line, an external data line can correspond to a plurality of pixel electrodes. Output, thereby reducing the use of the number of external pins of the source-level chip. Herein, the present invention effectively reduces the cost of the chip and increases the competitiveness and market advantage of the product virtually.

In the following, detailed descriptions will be made through specific embodiments in conjunction with the accompanying drawings to make it easier to understand the purpose, technical content, features and effects of the present invention.

The above is a description of the content of the present invention, and the following embodiments are used to demonstrate and explain the spirit and principle of the present invention, and provide a further explanation of the scope of the patent application of the present invention. Regarding the features, implementation, and effects of the present invention, the preferred embodiments with reference to the drawings are described in detail below.

In order to effectively improve the problem of controlling a single pixel electrode drive with a data line and a corresponding scanning line, that is, one-to-one driving, the present invention proposes a better improved design, which is a liquid crystal display control device . Among them, in order to better understand the technical content of the present invention, please refer to FIG. 2, where FIG. 2 is a schematic diagram of a liquid crystal display control device according to an embodiment of the present invention, as shown in FIG. The liquid crystal display control device 100 disclosed in the present invention includes a plurality of scan lines G _n , G _n-1 , G _n-2 , G _n-3 …, G ₁ , and a plurality of external data lines ( main data line) S ₁ , S ₂ ,..., S _m , a plurality of switching elements (Switch) 10a, 10b, 10c, and a plurality of pixel units 200a, 200b, 200c. Among them, each scanning line G _n , G _n-1 , G _n-2 , G _n-3 …, G ₁ transmits a scanning signal P _n , P _n-1 , P _n-2 , P _{n- 3} …, P ₁ , each external data line S ₁ , S ₂ ,…, S _m transmits a data signal Q ₁ , Q ₂ ,…, Q _{m respectively} . According to the embodiment of the present invention, the plurality of scanning lines G _n , G _n-1 , G _n-2 , G _n-3 ..., G _{1 are} connected to at least one gate chip 60, which is used to generate The scan signals P _n , P _n-1 , P _n-2 , P _n-3 …, P ₁ , and each scan line G _n , G _n-1 , G _n-2 , G _{n- 3} …, G ₁ transmits the scanning signals P _n , P _n-1 , P _n-2 , P _n-3 …, P ₁ , for example: the scanning line G _n transmits the scanning signal P _n , and the scanning line G _{n -1} transmits the scanning signal P _n-1 , and the scanning line G ₁ transmits the scanning signal P ₁ .

A source chip 80 is connected to the external data lines S ₁ , S ₂ ,..., S _m , and the source chip 80 is used to generate the data signals Q ₁ , Q ₂ ,..., Q _m . An external data line S ₁ , S ₂ , ..., S _m transmits data signals Q ₁ , Q ₂ , ..., Q _m , for example: an external data line S ₁ transmits a data signal Q ₁ , and an external data line S ₂ transmits a data signal Q _{2. The} external data line S _m transmits the data signal Q _m . According to an embodiment of the present invention, each of the external data lines S ₁ , S ₂ ,..., S _m is respectively connected to three sub data lines (11, 21, 31), so as to selectively use the children among them. The data lines 11, 21, 31 transmit data signals Q ₁ , Q ₂ , ..., Q _m .

In order to make your reviewing committee understand the technical content of the present invention more clearly, please refer to FIG. 3 together, which first uses a single external data line S ₁ as an illustration of an exemplary embodiment of the present invention. In detail, each switching element 10a, 10b, 10c is connected in parallel with each other, and each sub-data line is connected to a switching element. For example, sub-data line 11 is connected to switching element 10a, and sub-data line 21 is connected to switching element 10b. The sub data line 31 is connected to the switching element 10c. Thus, when the switching element 10a is turned on, the data signal Q ₁ may be the pixel to which the transmission unit 200a of the data line 11 via the sub. Similarly, when the control by the switching element 10b is turned on, the data signal Q ₁ 21 may be transmitted via the data lines to the sub-pixel units beneath 200b. When controlling the switching element 10c is turned on, the data signal Q ₁ may transmit the data lines 31 via the sub-pixel unit in which to 200c. Therefore, the present invention achieves the purpose of sequentially transmitting the data signal Q ₁ by controlling each of the switching elements 10a, 10b, and 10c to turn on sequentially, which is equivalent to selecting the corresponding sub data lines 11, 21, and 31.

As for how to control the turn-on of the switching elements 10a, 10b, and 10c, the liquid crystal display control device disclosed in the present invention may further include at least one demultiplexer 90, which is connected to the switching elements 10a. 10b, 10c, and are used to generate a plurality of branch signals D1, D2, D3, whereby the present invention can use each branch signal D1, D2, D3 to control the corresponding switching elements 10a, 10b, 10c to turn on sequentially. For example, when the splitter 90 outputs the shunt signal D1, the switching element 10a is turned on; when the splitter 90 outputs the shunt signal D2, the switching element 10b is turned on; when the splitter 90 outputs the shunt signal D3 At this time, the switching element 10c is turned on. In one embodiment, the switching elements 10a, 10b, and 10c are selected from a metal-oxide-semiconductor field-effect transistor (MOSFET). Thus, when the switching element 10a is turned on, the data signal Q ₁ may be the pixel to which the transmission unit 200a of the data line 11 via the sub. Similarly, when the switching element 10 b is turned on, the data signal Q ₁ can be transmitted to the pixel unit 200 b below it via the sub data line 21. When controlling the switching element 10c is turned on, the data signal Q ₁ may transmit the data lines 31 via the sub-pixel unit in which to 200c. Therefore, the liquid crystal display control device disclosed in the present invention uses the splitter 90 to sequentially generate the branch signals D1, D2, and D3 to sequentially control the opening of each of the switching elements 10a, 10b, and 10c. The corresponding sub data lines 11, 21, 31 can be selected to sequentially transmit the required data signals Q ₁ .

Below we will further explain the details of how the pixel unit performs the charging and discharging process after the data signal is output to the pixel unit. Please refer to FIG. 4 together, which uses a pixel unit 200a as an example. As shown in the figure, the pixel unit 200a is connected between two adjacent scanning lines Gn, Gn-1 and a sub data line 11, and the pixel unit 200a includes at least two thin film transistors (the first thin film transistor The crystal T1 and the second thin film transistor T2) and the corresponding at least two pixel capacitors (the first capacitor C1 and the second capacitor C2). The source of the first thin-film transistor T1 receives the data signal Q ₁ , the gate of the first thin-film transistor T1 receives the scanning signal P _n , and the drain of the first thin-film transistor T1 is connected to the first capacitor C1. The second thin-film transistor T2 is connected to the source of the second thin-film transistor T2. The second thin _- film transistor T2 is connected to the other scan signal P _n-1 and the drain of the second thin-film transistor T2 is connected to the second capacitor C2. . In other words, the first thin-film transistor T1 and the second thin-film transistor T2 are respectively connected to the first capacitor C1 and the second capacitor C2 so as to pass through the first thin-film transistor T1 and the first thin-film transistor T1 when the switching element 11 is turned on and the data signal Q _{1 is} input. The second thin film transistor T2 controls the charge and discharge of the first capacitor C1 and the second capacitor C2, respectively. In general, during the charging and discharging of the pixel capacitor, the scanning signals P _n and P _n-1 are used to control the switching states of the first thin film transistor T1 and the second thin film transistor T2 respectively. when the transistor T1 and the second thin film transistor T2 is turned on, the read data signals Q _1, a first thin film transistor T1 so that the first capacitor C1 and a second thin film transistor T2 according to the control data signals Q ₁ and connected thereto Charge and discharge of the second capacitor C2.

For example, please refer to FIG. 4 and FIG. 5 together. When the pixel unit 200a receives the data signal Q ₁ , the first capacitor C1 and the second capacitor C2 need to be charged first. The thin film transistor T1 and the second thin film transistor T2 are both turned on first to charge the first capacitor C1 and the second capacitor C2 at the same time. After that, when the charging is completed, the second thin film transistor T2 is turned off, and the first capacitor C1 is charged or discharged to the required potential according to the required voltage level. In an embodiment, if the voltage level required for the second capacitor C2 is higher than the first capacitor C1, the second thin film transistor T2 is first completed to charge the second capacitor C2, and then the second thin film transistor T2 is turned off. The first capacitor C1 is discharged to the required voltage level. As shown in Figure 6, if the second capacitor C2 is charged to 5 volts and the first capacitor C1 only needs 3 volts, When the crystal T1 and the second thin film transistor T2 are both turned on, the first capacitor C1 and the second capacitor C2 are both charged to 5 volts. After the second thin film transistor T2 is turned off, the first capacitor C1 is discharged from 5 volts to 3 volts.

In another embodiment, if the voltage level required by the first capacitor C1 is higher than the second capacitor C2, the second thin film transistor T2 is first completed charging the second capacitor C2, and then the second thin film transistor is turned off. T2, and the first capacitor C1 continues to charge to the required voltage level. As shown in Figure 7, if the second capacitor C2 is charged to 3 volts and the first capacitor C1 needs 5 volts, When the crystal T1 and the second thin film transistor T2 are both turned on, the first capacitor C1 and the second capacitor C2 are first charged to 3 volts. After the second thin film transistor T2 is turned off, the first capacitor C1 continues to be charged from 3 volts to 5 volts.

FIG. 8 is a schematic diagram of the scanning signal and the branch signal waveform of the liquid crystal display control device according to the embodiment of the present invention. As shown in the figure, this embodiment uses n = 2561, and the splitter generates three branches. The road signals D1, D2, and D3 are taken as an example to explain. From this viewpoint, the present invention uses a shunt to sequentially output the shunt signals D1, D2, and D3 to control the corresponding switching elements 10a, 10b, and 10c. Open sequentially. When the switching element 10a, 10b, 10c are sequentially turned on, it is equivalent to each of the data signals _{Q 1, Q 2, ...,} Q m Jieke sequentially transmitted through the sub-data lines 11, 21, to sequentially drive The pixel units 200a, 200b, and 200c underneath charge and discharge the electrodes. Since the liquid crystal display control device disclosed in the present invention is designed, each pixel unit is controlled by a sub data line, and each pixel unit includes at least two sets of pixel electrodes (each of which is controlled by a thin film transistor) Pixel capacitors can be charged and discharged, which can be regarded as a set of pixel electrodes). Based on the inventor's design, each external data line is connected to three sub-data lines, and the data signals can be selectively used in order. One of them is used for transmission. The present invention can realize the output of an external data line corresponding to a plurality of pixel electrodes. Taking the implementation example of FIG. 3 of the present invention as an example, it satisfies the output of a single external data line corresponding to six pixel electrodes, significantly improves the problem of one-to-one driving of the conventional liquid crystal display panel, and further reduces the external data. Line usage target.

Therefore, according to the technical content taught by the present invention, those with ordinary knowledge in the art can change their design on the actual implementation level, which all belong to the scope of the present invention. Compared with the conventional technology, the present invention effectively improves the problem of controlling a single pixel electrode drive with a data line and a corresponding scanning line, that is, one-to-one driving, which is achieved by designing each external data line A plurality of sub data lines can be connected respectively, and the switching elements are controlled to be sequentially turned on, so as to selectively use these sub data lines to sequentially transmit data signals. By comparing the embodiments shown in Figures 2 and 3 of the present invention with the prior art, it can be clearly seen that the connection of the thin film transistor designed according to the present invention to the sub data line and the external data line can make the The number of uses has been greatly reduced to 1/3 of the previous technology. It is known that the number of external data lines affects the circuit structure of the source chip, so the present invention can anticipate and effectively reduce the manufacturing cost of the source chip.

In summary, the liquid crystal display control device disclosed in the present invention does have excellent industrial applicability and competitiveness. It is obvious that the technical features, methods, and effects achieved by the present invention are significantly different from the existing schemes. They are not for those who are familiar with the technology to easily complete them. Therefore, they should have patent requirements. .

10‧‧‧ Pixel electrode

10a, 10b, 10c‧‧‧ Switching element

11‧‧‧Sub data line

12‧‧‧scan line

14‧‧‧ Data Line

21‧‧‧Sub data line

31‧‧‧Sub data line

60‧‧‧Gate Chip

80‧‧‧source chip

90‧‧‧ Splitter

100‧‧‧LCD display control device

200a, 200b, 200c ‧‧‧ pixel units

FIG. 1 is a schematic diagram of a single-gate circuit architecture of the conventional technology. FIG. 2 is a schematic diagram of a liquid crystal display control device according to an embodiment of the present invention. FIG. 3 is a schematic diagram of a liquid crystal display control device according to an exemplary embodiment of the present invention. FIG. 4 is a schematic diagram of an equivalent circuit of a pixel unit according to an embodiment of the present invention. FIG. 5 is a schematic diagram of charging and discharging of a pixel unit according to an embodiment of the present invention. FIG. 6 is a schematic diagram of discharging a first capacitor according to an embodiment of the present invention. FIG. 7 is a schematic diagram of charging a first capacitor according to an embodiment of the present invention. FIG. 8 is a waveform diagram of the scanning signal and the branch signal of the liquid crystal display control device according to the embodiment of the present invention.

Claims (11)

A liquid crystal display control device includes: a plurality of scanning lines transmitting a plurality of scanning signals, wherein each of the scanning lines transmitting a scanning signal; a plurality of external data lines transmitting a plurality of data signals, each of which An external data line transmits one of the data signals, and each of the external data lines is respectively connected to three sub data lines to selectively use one of the sub data lines to transmit one data signal; a plurality of switching elements are connected to the Each of the sub data lines is connected to a switching element, and each of the switching elements is connected in parallel with each other, and each of the switching elements is controlled to be sequentially turned on to transmit a corresponding one of the sub data lines. The data signal; and a plurality of pixel units, each of which is connected between two adjacent scanning lines and one of the sub data lines, wherein each of the pixel units includes at least two thin-film electrical units The crystal and the corresponding at least two pixel capacitors to control each of the pixel units to sequentially receive a data signal when each of the switching elements is sequentially turned on, so that the thin films are electrically Body controlling the plurality of pixel capacitors for selectively charging or discharging the voltage to a desired level. The liquid crystal display control device according to claim 1, further comprising at least one gate chip connected to the scan lines. The gate chip generates the scan signals and transmits each scan line using each of the scan lines. The scan signal. The liquid crystal display control device according to claim 1, further comprising at least one source chip connected to the external data lines. The source chip generates the data signals and transmits each of the external data lines. Data signals. The liquid crystal display control device according to claim 1, wherein the thin film transistor systems of each of the pixel units include a first thin film transistor and a second thin film transistor, and the pixel capacitors include a first A capacitor and a second capacitor, the first thin film transistor and the second thin film transistor system respectively connecting the first capacitor and the second capacitor to pass through the first thin film transistor when a switching element is turned on The second thin film transistor and the second thin film transistor respectively control the charging and discharging of the first capacitor and the second capacitor. The liquid crystal display control device according to claim 4, wherein the source of the first thin film transistor receives the data signal, and the gate of the first thin film transistor receives the scanning signal, the first film The drain of the transistor is connected to the source of the second thin film transistor after being connected to the first capacitor, and the gate of the second thin film transistor is to receive another scanning signal adjacent to the second thin film transistor. The drain is connected to the second capacitor. The liquid crystal display control device according to claim 5, wherein the scanning signals control a switching state of the first thin film transistor and the second thin film transistor, so that the first thin film transistor and the second thin film transistor The crystal can control the charging and discharging of the first capacitor and the second capacitor according to a data signal. The liquid crystal display control device according to claim 6, wherein when a pixel unit receives the data signal, the first thin film transistor and the second thin film transistor system are first turned on to simultaneously A capacitor is charged with the second capacitor. The liquid crystal display control device according to claim 7, wherein when the voltage level required by the first capacitor is higher than the second capacitor, the second thin film transistor system completes charging the second capacitor first, and then turns off. The second thin film transistor and the first capacitor are continuously charged to a desired voltage level. The liquid crystal display control device according to claim 7, wherein when the voltage level required by the second capacitor is higher than the first capacitor, the second thin film transistor system completes charging the second capacitor first, and then turns off. The second thin film transistor and the first capacitor are discharged to a desired voltage level. The liquid crystal display control device according to claim 1, further comprising at least one splitter connected to the switching elements, wherein the splitter is used to generate a plurality of split signals for controlling each of the split signals. Each of the corresponding switching elements is turned on in sequence. The liquid crystal display control device according to claim 1, wherein each of the switching elements is a metal-oxide-half field-effect transistor (MOSFET).