TWI823078B - Source driver chips that can reduce heat energy generation and liquid crystal displays and information processing devices that utilize them - Google Patents

Abstract

A source driver chip that can reduce heat energy generation has: a polarity conversion detection unit used to detect whether there are two display data in the same row in the front and back columns of display data with opposite polarities. If so, a The first detection result is in the active state. If not, the first detection result is in the inactive state and a signal of the same polarity is in the active state; a data voltage change detection unit is used to detect the signal of the same polarity in the active state. When the active state is present, it is judged whether the numerical difference between the two display data of the same row is greater than a threshold, and if so, a second detection result is presented in the active state; and a switch circuit is used to perform the first When the detection result or the second detection result shows an active state, a charge sharing operation is performed on a TFT liquid crystal array, so that the pixel capacitances in two adjacent data channels of the TFT liquid crystal array are redistributed.

Description

Source driver chips that can reduce heat energy generation and liquid crystal displays and information processing devices that utilize them

The present invention relates to a source driver chip, in particular to a source driver chip that can reduce heat energy generation.

In order to reduce the heat energy generated by the liquid crystal display during operation, charge sharing technical solutions have been proposed. Please refer to FIG. 1a, which illustrates a block diagram of a charge sharing control circuit of a conventional liquid crystal display. As shown in Figure 1a, the charge sharing control circuit includes a timing controller 10, a source driver 21 and a TFT liquid crystal array 30. The source driver 21 includes a charge sharing driving unit 21a and a source driving unit 21b. .

The timing controller 10 is used to transmit display data to the source driver 21 through a display data signal S _DISP ; the charge sharing driving unit 21a is used to periodically and unconditionally output a charge sharing control signal C _CS to the source driving unit 21b A switching circuit inside the source driving unit 21b is driven, so that the pixel capacitors in each column of the TFT liquid crystal array 30 are charged with charge in pairs before charging the pixel capacitors in each column of the TFT liquid crystal array 30 with the pixel voltage corresponding to the display data.

Please refer to FIG. 1b, which illustrates an operating timing diagram of the charge sharing control circuit of FIG. 1a. As shown in Figure 1b, each pixel voltage establishment period includes a charge sharing period T _S and a pixel voltage driving period T _DRV . Among them, the source driving unit 21b, regardless of whether each two of its output channels output Will the adjacent pixel voltages have opposite polarity, that is, whether it is (+,-), (+,+), (-,-) or (-,+), during each charge sharing period T _S will cause each odd-numbered output channel Y _2n-1 in the plurality of output channels to share charges with an adjacent even-numbered output channel Y _2n , so that at the end of the charge sharing period T _S , the odd-numbered output channel Y _2n- The voltages of ₁ and even output channels Y _2n both reach an intermediate voltage V _DD2M , where the polarity + represents that the pixel voltage is higher than the intermediate voltage V _DD2M , and the polarity - represents that the pixel voltage is lower than the intermediate voltage V _DD2M .

However, when the voltage polarity of two temporally adjacent pixels output by each output channel is the same and the value remains unchanged, the charge sharing control circuit in Figure 1a will have redundant charging and discharging processes and generate redundant heat energy.

In addition, please refer to FIG. 2a, which illustrates a block diagram of a charge sharing control circuit of another conventional liquid crystal display. As shown in Figure 2a, the charge sharing control circuit includes a timing controller 10, a source driver 22 and a TFT liquid crystal array 30. The source driver 22 includes a polarity conversion detection unit 22a and a source driving unit. 22b.

The timing controller 10 is used to transmit display data to the source driver 22 through a display data signal S _DISP ; the polarity change detection unit 22a is used to detect two displays located in the same row among the two columns of display data. When the corresponding voltage polarity of the data is opposite, a charge sharing enable signal C _CS becomes active, and when the charge sharing enable signal C _CS becomes active, the source driving unit 22b drives one of its internal switching circuits to drive the TFT. Two corresponding data channels of the liquid crystal array 30 share charges to save the amount of charge required to establish the next pixel voltage on the pixel capacitor.

Please refer to FIG. 2b, which illustrates an operating timing diagram of the charge sharing control circuit of FIG. 2a. As shown in Figure 2b, each pixel voltage establishment period includes a charge sharing period _TS and a pixel voltage driving period T _DRV , in which the source driving unit _22b outputs two When adjacent pixel voltages have opposite polarities (+,-), a charge sharing period T _S between (+,-) will cause the odd-numbered output channel Y _2n-1 to be connected to an adjacent even-numbered output channel. Y _2n performs charge sharing, so that at the end of the charge sharing period _TS , the voltages of the odd output channel Y _2n-1 and the even output channel Y _2n both reach an intermediate voltage V _DD2M ; while the voltage output by the odd output channel Y _2n-1 When the voltage polarity of two adjacent pixels is the same (+, +), the odd-numbered output channel Y _2n-1 and the adjacent even-numbered output channel Y _2n are not allowed to share charges.

The charge sharing control circuit in Figure 2a can avoid redundant charging and discharging processes when the voltage polarity of two adjacent pixels output by each output channel is the same and the value remains unchanged. The voltage polarity of two adjacent pixels in time is the same, but when the value changes from large to small or from small to large, a large amount of charge will still flow and heat energy will be released.

In order to solve the above problems, a novel source driver chip is urgently needed in this field.

One object of the present invention is to provide a source driver chip that can reduce the generation of heat energy and can perform charge sharing on a TFT liquid crystal array when there are two display data in the same row in the front and back columns of display data with opposite polarities. Operation, and performing the charge sharing operation on the TFT liquid crystal array when the polarity of the two display data in the same row is the same but the numerical difference is greater than a threshold, thereby further reducing the heat energy generated by a liquid crystal display.

Another object of the present invention is to provide a liquid crystal display that can perform a charge sharing operation on a TFT liquid crystal array when there are two display data in the same row in the front and back columns of display data with opposite polarities, and in the When the polarity of two display data in the same row is the same but the numerical difference is greater than a threshold, the charge sharing operation is performed on the TFT liquid crystal array, thereby further reducing the heat energy generated by the liquid crystal display.

Another object of the present invention is to provide an information processing device, which has the aforementioned liquid crystal display and can reduce the heat energy generated by the liquid crystal display.

In order to achieve the aforementioned goals, a source driver chip that can reduce heat energy generation is proposed, which has:

A polarity change detection unit is used to detect whether there are two display data in the same row in the previous and next columns of display data with opposite polarities. If so, a first detection result is presented in an active state. If not, then Make the first detection result appear inactive state, and make a signal with the same polarity appear in active state;

A data voltage change detection unit, used to determine whether the numerical difference between the two display data of the same row is greater than a threshold when the signal of the same polarity is in the action state. If so, a second detection result is obtained. Present the active state, if not, make the second detection result present the inactive state; and

A switch circuit for performing a charge sharing operation on a TFT liquid crystal array when the first detection result or the second detection result is in an active state, so that two adjacent data channels of the TFT liquid crystal array The pixel capacitor performs charge redistribution.

In one embodiment, the polarity change detection unit has a register unit to temporarily store the display data of at least one column.

In one embodiment, the data voltage change detection unit has a register unit to temporarily store the display data of at least one column.

In order to achieve the aforementioned goals, the present invention further proposes a liquid crystal display, which has a source driver chip that can reduce heat energy generation and a TFT liquid crystal array. The source driver chip that can reduce heat energy generation has:

A polarity change detection unit is used to detect whether there are two display data in the same row in the previous and next columns of display data with opposite polarities. If so, a first detection result is presented in an active state. If not, then Make the first detection result appear inactive state, and make a signal with the same polarity appear in active state;

A data voltage change detection unit, used to determine whether the numerical difference between the two display data of the same row is greater than a threshold when the signal of the same polarity is in the action state. If so, a second detection result is obtained. Present the active state, if not, make the second detection result present the inactive state; and

A switch circuit for performing a charge sharing operation on the TFT liquid crystal array when the first detection result or the second detection result is in an active state, so that two adjacent data channels of the TFT liquid crystal array The pixel capacitor performs charge redistribution.

In one embodiment, the liquid crystal display further has a timing controller to transmit the display data to the source driver chip that can reduce heat energy generation.

In one embodiment, the polarity change detection unit has a register unit to temporarily store the display data of at least one column.

In one embodiment, the data voltage change detection unit has a register unit to temporarily store the display data of at least one column.

In order to achieve the above object, the present invention further proposes an information processing device, which has a central processing unit and the aforementioned liquid crystal display.

In possible embodiments, the information processing device may be a portable computer or an intelligent handheld device.

The principle of the present invention is:

(1) When there are two display data in the same row in the front and back columns of display data with opposite polarities, a first detection result will be in an active state; otherwise, the first detection result will be in an inactive state. ;

(2) When the first detection result is in an inactive state, if the numerical difference between two display data in the same row is greater than a threshold, a second detection result is made in an active state; otherwise, the second detection result is in an active state. The second detection result is inactive; and

(3) Driving a switch circuit to perform a charge sharing operation on a TFT liquid crystal array when the first detection result or the second detection result is in an active state.

Accordingly, the present invention can further save the power consumption of the TFT liquid crystal array, thereby reducing the heat energy generated by the liquid crystal display.

Please refer to FIG. 3 , which illustrates a block diagram of a liquid crystal display including a source driver chip that can reduce heat energy generation of the present invention. As shown in FIG. 3 , a liquid crystal display 100 includes a timing controller 110 , a source driver chip 120 that can reduce heat energy generation, and a TFT liquid crystal array 130 . In order to highlight the technical features of the present invention, other components of the liquid crystal display 100 that are not directly related to the present invention, such as gate driver chips and backlight modules, are not shown in FIG. 3 .

The timing controller 110 is used to transmit display data to the source driver chip 120 that can reduce heat energy generation through a display data signal S _DISP .

The source driver chip 120 that can reduce heat energy generation has a polarity change detection unit 121, a data voltage change detection unit 122 and a switch circuit 123.

The polarity change detection unit 121 is used to detect whether there are two display data in the same row in the previous and next columns of display data with opposite polarities. If so, make a first detection result S _CS1 appear in the active state. Otherwise, Then, the first detection result S _CS1 is made to be in an inactive state, and a signal S _PSM of the same polarity is made to be in an active state. In addition, the polarity change detection unit 121 may have a register unit to temporarily store the display data of at least one column.

The data voltage change detection unit 122 is used to determine whether the numerical difference between the two display data of the same row is greater than a threshold when the signal S _PSM of the same polarity is in the active state. If so, a second detection result S _CS2 is in the active state. Otherwise, the second detection result S _CS2 is in the inactive state. In addition, the data voltage change detection unit 122 may have a register unit to temporarily store the display data of at least one column.

The switch circuit 123 is used to perform a charge sharing operation on the TFT liquid crystal array 130 when the first detection result S _CS1 or the second detection result S _CS2 is in an active state, so that two adjacent ones of the TFT liquid crystal array 130 The pixel capacitors in the data channel redistribute charge, thereby reducing the settling time of new pixel voltages.

According to the above description, the present invention further provides an information processing device. Please refer to FIG. 4 , which illustrates a block diagram of an embodiment of the information processing device of the present invention. As shown in FIG. 4 , an information processing device 200 has a central processing unit 210 and a liquid crystal display 220 , wherein the central processing unit 210 is used to communicate with the liquid crystal display 220 and the liquid crystal display 220 is implemented by the liquid crystal display 100 . In addition, the information processing device 200 can be a portable computer or an intelligent handheld device.

According to the above description, the present invention can provide the following advantages:

1. The source driver chip of the present invention that can reduce the generation of heat energy can perform a charge sharing operation on a TFT liquid crystal array when there are two display data in the same row in the front and back columns of display data with opposite polarities, and in all cases When the polarity of the two display data in the same row is the same but the numerical difference is greater than a threshold, the charge sharing operation is performed on the TFT liquid crystal array, thereby further reducing the heat energy generated by a liquid crystal display.

2. The liquid crystal display of the present invention can perform a charge sharing operation on a TFT liquid crystal array when there are two display data in the same row in the front and back columns of display data with opposite polarities, and when the two display data in the same row have opposite polarities, When the polarity of the data is the same but the numerical difference is greater than a threshold, the charge sharing operation is performed on the TFT liquid crystal array, thereby further reducing the heat energy generated by the liquid crystal display.

3. The information processing device of the present invention can reduce the heat energy generated by having the aforementioned liquid crystal display.

What is disclosed in the present invention is one of the preferred embodiments. Any partial changes or modifications derived from the technical ideas of the present invention and easily inferred by those skilled in the art will not depart from the scope of the patent rights of the present invention.

To sum up, regardless of the purpose, means and effects of this case, it shows that it is completely different from the conventional technology, and that the invention is practical first, and indeed meets the patent requirements for inventions. I sincerely ask the review committee to take a clear look and grant the patent as soon as possible for your benefit. Society is a prayer for the Supreme Being.

10: Timing controller 21: Source driver 21a: Charge sharing drive unit 21b: Source driver unit 22: Source driver 22a: Polarity change detection unit 22b: Source driver unit 30:TFT LCD array 100:LCD display 110: Timing controller 120: Source driver chip that can reduce heat energy generation 121: Polarity change detection unit 122: Data voltage change detection unit 123: Switch circuit 130:TFT LCD array 200:Information processing device 210:Central processing unit 220:LCD display

In order to further disclose the specific technical content of the present invention, please first refer to the drawings, in which: FIG. 1a shows a block diagram of a charge sharing control circuit of a conventional liquid crystal display. FIG. 1b illustrates an operating timing diagram of the charge sharing control circuit of FIG. 1a. FIG. 2a shows a block diagram of a charge sharing control circuit of another conventional liquid crystal display. FIG. 2b illustrates an operating timing diagram of the charge sharing control circuit of FIG. 2a. FIG. 3 is a block diagram of a liquid crystal display including a source driver chip capable of reducing heat energy generation of the present invention. FIG. 4 is a block diagram of an embodiment of the information processing device of the present invention.

100:LCD display

110: Timing controller

120: Source driver chip that can reduce heat energy generation

121: Polarity change detection unit

122: Data voltage change detection unit

123: Switch circuit

130:TFT LCD array

Claims (5)

A source driver chip that can reduce heat energy generation has: a polarity conversion detection unit used to detect whether there are two display data in the same row in the front and back columns of display data with opposite polarities. If so, A first detection result is in an active state. If not, the first detection result is in an inactive state and a signal of the same polarity is in an active state; a data voltage change detection unit is used to detect when the polarity is the same. When the signal is in the active state, it is judged whether the numerical difference between the two display data in the same row is greater than a threshold. If so, a second detection result is made in the active state. If not, the second detection result is made in the active state. The result is in an inactive state; and a switch circuit is used to perform a charge sharing operation on a TFT liquid crystal array when the first detection result or the second detection result is in an active state, so that both sides of the TFT liquid crystal array The pixel capacitances in two adjacent data channels perform charge redistribution; wherein, the polarity change detection unit and the data voltage change detection unit both have a register unit to temporarily store the display data of at least one column. A liquid crystal display, which has a source driving chip that can reduce the generation of heat energy and a TFT liquid crystal array. The source driving chip that can reduce the generation of heat energy has: a polarity change detection unit for detecting the front and rear columns. Whether there are two display data of the same row in the display data with opposite polarity. If so, make a first detection result appear in the active state. If not, make the first detection result appear in the inactive state and make a polarity The same signal is in the active state; a data voltage change detection unit is used to determine whether the numerical difference between the two display data of the same row is greater than a threshold when the signal of the same polarity is in the active state. If so, then A second detection result is in an active state, if not, the second detection result is in an inactive state; and a switch circuit is used to display the active state when the first detection result or the second detection result is When performing a charge sharing operation on the TFT liquid crystal array, the pixel capacitances in the two adjacent data channels of the TFT liquid crystal array are redistributed; wherein, the polarity change detection unit and the data voltage change detection unit Each measurement unit has a register unit to temporarily store the display data of at least one column. The liquid crystal display as described in item 2 of the patent application further has a timing controller to transmit the display data to the source driver chip that can reduce heat energy generation. An information processing device having a central processing unit and a liquid crystal display as described in any one of items 2 to 3 of the patent application, wherein the central processing unit is used to communicate with the liquid crystal display. For example, the information processing device described in item 4 of the patent application scope is a portable computer or an intelligent handheld device.

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