CN118887894A - Source driver, display driver chip, display device and driving method - Google Patents

Abstract

The present disclosure provides a source driver, a display driver chip, a display device and a driving method. In the screen-off display mode, the source driver receives pixel data of at least one column of pixels through the driver controller, generates a driving enable signal when the level of the pixel data of at least one column of pixels reaches a preset condition, and provides the driving enable signal to the output buffer by multiplexing the invalid driving channel between the output end of the driver controller and the output buffer, and enables the connection path between the output buffer and the at least one column of pixels to be disconnected. In this way, efficient data display can be achieved in the screen-off display mode, and the purpose of saving power consumption can be achieved without affecting the display effect.

Description

Source driver, display driver chip, display device and driving method

Technical Field

The present disclosure relates to the field of display technology, and in particular to a source driver, a display driver chip, a display device and a driving method.

Background Art

The display device includes a display panel and its driving circuit. Taking a liquid crystal display device as an example, the display panel is driven by a gate driver and a source driver and is connected to a timing controller. The timing controller provides a scanning signal to control the timing of transmitting a data signal from the source driver to the display panel.

Fig. 1 shows a schematic diagram of a display device. As shown in Fig. 1, the display device 100 includes a display panel 101 and a source driver 110. For example, the display panel 101 and the source driver 110 are connected by using a chip on film (COF) packaging process, and the source driver 110 can be located on one side or multiple sides of the display panel.

The display panel 101 has a transistor array composed of multiple thin film transistors and a pixel array composed of multiple pixel capacitors (see FIG. 1 ). The display panel has ports electrically connected to multiple data lines for receiving driving signals provided by the source driver 110 .

The source driver 110 is applied to the display device 100 and can provide data signals to the pixel array of the display screen to control each pixel on the display screen to display the target brightness, thereby constructing a complete image. The source driver 110 includes a multi-level driving channel, and the number of the driving channels is not less than the number of the data lines. The multi-level driving channel includes an effective driving channel 111 and an invalid driving channel 112. The number of effective driving channels 111 corresponds to the number of data lines. The multiple effective driving channels 111 are respectively connected to the corresponding data lines and provide corresponding driving signals. The output ends of the multiple invalid driving channels 112 are idle.

In the prior art, in order to reduce the power consumption of the display screen and increase the battery life of the display screen, most of the current technologies use a technical method of reducing the refresh rate, such as the always on display (AOD) mode. The always on display (AOD) mode refers to the function of keeping part of the screen lit for a long time to display time, fingerprint icons, notification messages and other content without lighting up the entire screen. However, battery life is still a common shortcoming of display devices. In order to reduce the power consumption of display devices as much as possible, the power consumption requirements of display driver chips are particularly stringent.

Summary of the invention

In order to solve the above technical problems, the present disclosure provides a source driver, a display driver chip, a display device and a driving method, which can realize efficient data display in the screen-off display mode and save power consumption without affecting the display effect.

In one aspect, the present disclosure provides a source driver for driving a display panel, comprising a plurality of driving channels, each driving channel providing a driving voltage to at least one column of pixels of the display panel through an output buffer, wherein the source driver further comprises:

a driving controller, wherein an input end of the driving controller is connected to input ends of the plurality of driving channels, and is used to receive pixel data of the at least one column of pixels in an off-screen display mode, and to generate a driving enable signal when a level of the pixel data of the at least one column of pixels reaches a preset condition,

The source driver provides the drive enable signal to the output buffer by multiplexing the invalid drive channel between the output end of the drive controller and the output buffer, and enables the connection path between the output buffer and the at least one column of pixels to be disconnected.

In some embodiments, the preset condition is that the levels of the pixel data of the at least one column of pixels are all in a zero potential state.

In some embodiments, each drive channel includes:

a plurality of buffers, wherein the plurality of buffers receive and store pixel data of the at least one column of pixels through an input terminal of the source driver;

A plurality of first selection switches, wherein input ends of the plurality of first selection switches are respectively connected to a buffer;

A level converter, the input end of which is commonly connected to the output ends of the plurality of first selection switches, for receiving the pixel data output by the strobe, and performing level conversion on the pixel data before outputting it;

A digital-to-analog converter, the input end of which is connected to the output end of the level converter, and is used to select a grayscale voltage output of a corresponding level according to the pixel data,

The input end of the output buffer is connected to the output end of the digital-to-analog converter, and is used to drive each data line to a driving voltage corresponding to the grayscale voltage.

In some embodiments, the plurality of buffers include:

a plurality of first buffers, wherein the plurality of first buffers receive and store pixel data of the at least one column of pixels through an input terminal of the source driver;

A plurality of second buffers are respectively connected between a first buffer and a first selection switch.

In some embodiments, the output buffer comprises an operational amplifier.

In some embodiments, each drive channel further comprises:

an output switch connected between an output terminal of the output buffer and ground;

At least one invalid driving channel, the output end of the invalid driving channel is connected to the control end of the output switch.

In some embodiments, the invalid driving channel includes a first buffer, a second buffer and a level converter.

The first buffer, the second buffer and the level converter are sequentially connected in series between the driving controller and the output buffer, and the output end of the level converter is also connected to the control end of the output switch.

In some embodiments, the source driver further comprises:

a plurality of second selection switches, wherein the input end of each second selection switch is commonly connected to the output end of the output buffer, the output end of each second selection switch is respectively connected to the data line corresponding to a column of pixels, and each second selection switch and each first selection switch are mapped one by one to the data line corresponding to a column of pixels; and

A plurality of third selection switches, each of the third selection switches is respectively connected between output terminals of the level converters of adjacent driving channels.

On the other hand, the present disclosure further provides a display driver chip, which includes the source driver as described above.

On the other hand, the present disclosure provides a display device, comprising:

display panel; and

The source driver as mentioned above is used to drive the display panel.

In some embodiments, the display device includes one or a combination of a mobile phone, a tablet computer, a laptop computer, a desktop computer, a television, and a car display.

On the other hand, the present disclosure further provides a driving method applied to the above-mentioned source driver, wherein the source driver is used to drive a display panel, and includes a plurality of driving channels, each driving channel providing a driving voltage to at least one column of pixels of the display panel through an output buffer, wherein the driving method includes:

In the screen-off display mode, the driving controller is used to receive pixel data of at least one column of pixels, and a driving enable signal is generated when the level of the pixel data of the at least one column of pixels reaches a preset condition;

By multiplexing the invalid driving channel between the output end of the driving controller and the output buffer, the driving enable signal is provided to the output buffer, and the connecting path between the output buffer and the at least one column of pixels can be controlled to be disconnected.

In some embodiments, the preset condition is that the levels of the pixel data of the at least one column of pixels are all in a zero potential state.

The beneficial effects of the present disclosure are as follows: the present disclosure provides a source driver, display, driver chip display device and driving method, wherein the source driver receives pixel data of at least one column of pixels through the driver controller in the off-screen display mode, and generates a driving enable signal when the level of the pixel data of at least one column of pixels reaches a preset condition, and provides the driving enable signal to the output buffer by reusing the invalid driving channel between the output end of the driver controller and the output buffer, and enables the connection path between the output buffer and the at least one column of pixels to be disconnected. In this way, in the off-screen display mode, the judgment results of pixel data of different colors are obtained through the additional circuit, and then the original invalid driving channel circuit is reused to turn off the pixel drive with some data of zero, so as to realize efficient data display and save power consumption without affecting the display effect.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings.

FIG1 shows a schematic diagram of a display device in the prior art;

FIG2 is a schematic diagram showing an equivalent circuit of the display device shown in FIG1 ;

FIG3 is a schematic diagram showing the display effect of an existing display device in a screen-off display mode;

FIG4 is a schematic diagram showing the structure of a source driver provided by an embodiment of the present disclosure;

FIG5 is a schematic structural diagram of a driving channel in the source driver shown in FIG4 ;

FIG6 is a schematic diagram showing a picture accounting for 50% in the screen-off display mode in a specific embodiment;

FIG. 7 is a schematic flow chart of a driving method for the source driver provided in an embodiment of the present disclosure.

DETAILED DESCRIPTION

In order to facilitate the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure can be implemented in different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the content of the present disclosure more thorough and comprehensive.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs. The terms used in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure.

Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings.

FIG2 shows an equivalent circuit diagram of the display device shown in FIG1. In FIG2, taking a liquid crystal display device as an example, the display device 100 includes a source driver 110, a gate driver 120, a plurality of thin film transistors T (thin film transistor, TFT), and a plurality of pixel capacitors C _LC formed between a pixel electrode and a common electrode. The plurality of thin film transistors T constitute a transistor array, and the plurality of pixel capacitors C _LC constitute a pixel array. The gate driver 120 is respectively connected to the gates of the thin film transistors T of the corresponding rows via a plurality of scanning lines G1 to Gm, and is used to provide gate voltages G1 to Gm in a scanning manner, so as to select thin film transistors of different rows in an image frame cycle. The source driver 110 is respectively connected to the source electrodes of the thin film transistors T of the corresponding columns via a plurality of data lines S1 to Sn, and is used to provide grayscale voltages corresponding to grayscale to the plurality of thin film transistors T of each column when the plurality of thin film transistors T of each row are selected. Wherein, m and n are natural numbers. The drain electrodes of the plurality of thin film transistors T are respectively connected to a corresponding pixel capacitor C _LC . In the gated state, the source driver 110 applies the grayscale voltage to the pixel capacitor C _LC via the data line and the thin film transistor T. The voltage on the pixel capacitor C _LC acts on the liquid crystal molecules, thereby changing the orientation of the liquid crystal molecules to achieve a transmittance corresponding to the grayscale. In order to maintain the voltage between pixel update cycles, the pixel capacitor C _LC can be connected in parallel with the storage capacitor Cs to obtain a longer holding time.

In each embodiment of the present disclosure, a liquid crystal display device is used as an example to illustrate the internal structure and connection relationship of the display device, but the display device of the present invention is not limited to a liquid crystal display device. The display device can be applied to various fields, and the display device can be, for example, a display screen with a display function or a touch display function, a wearable display device (such as a bracelet, a watch, glasses, and a helmet, etc.), a television, a tablet computer, a laptop computer, a mobile phone, a digital photo frame, a navigator, and other products or components. Of course, the touch display device provided in the embodiment of the present disclosure is not limited to the types listed above.

Generally speaking, the source driver should be able to drive various display panels with different resolutions so that it can be suitable for display panels in various scenarios. The horizontal resolution of the display panel should not exceed the maximum resolution supported by the source driver.

The display panel has a transistor array composed of multiple thin film transistors and a pixel array composed of multiple pixel capacitors (see FIG. 1 ). The display panel has a port electrically connected to multiple data lines for receiving a driving signal provided by the source driver 110 .

The source driver 110 includes a multi-stage driving channel, the number of which is not less than the number of the data lines. The multi-stage driving channel includes an effective driving channel 111 and an invalid driving channel 112, the number of the effective driving channels 111 corresponds to the number of the data lines, or the number of the data lines is n times the number of the effective driving channels 111, where n is a positive integer.

In some types of products, each effective drive channel 111 may include, for example, a shift register, a data buffer, a display buffer, and a source channel. The effective drive channel 111 is connected to the corresponding data line in the display panel 101, and is used to drive the pixel capacitor of the corresponding row in the display panel 101 to drive the display panel 101. Among them, the shift register is used to generate an enable signal to turn on the data buffer, and the shift register is, for example, a D-type flip-flop (DFF). The data buffer is used to cache the data signal data according to the enable signal, and the data signal data is the data signal required to display the next frame of the display screen. The display buffer is used to cache the data signal required to display the current frame of the display screen. When the current frame of the display screen is displayed and the data signal of the next frame of the display screen cached by the data buffer is cached, the display buffer receives and caches the data signal required for the next frame of the display screen cached by the data buffer. The source channel is used to receive the data signal required for the current frame of the display screen cached by the display buffer, and convert the data signal into a drive signal to drive the display panel 101, and the drive signal is, for example, a grayscale signal.

Of course, the above is a description of one type of drive channel structure, which is only used as an example to facilitate understanding of its working principle, and is not intended to be a limitation on the embodiments of the present disclosure. In other alternative implementations, the following drive channel structure or other alternative structure description may be used to expand the description, which is not limited here.

At the same time, compared with the effective driving channel 111, the difference between the invalid driving channel 112 is that the source channel in the invalid driving channel 112 is not connected to the display panel 101, so that no driving signal is provided to the display panel 101, and the similarities with the effective driving channel 111 are not repeated here.

In a traditional source driver, the invalid drive channel and the valid drive channel receive the shift clock signal step by step, and only a few preset resolutions can be selected, and the matching freedom between the source driver and the display panel is low. In addition, the invalid drive channel is generally used as a backup replacement. When there is no abnormality in the valid drive channel in use, it is usually not working, which to a certain extent causes the resource utilization to be reduced. In order to extend the battery life and reduce power consumption, the existing display devices mostly use the screen-off display technology, as shown in Figure 3. However, during the screen-off display process, sometimes the pixel part corresponding to the black background is still displayed through the pixel driver, which leads to the system power consumption is still high, which is not conducive to improving resource utilization and reducing costs and power consumption.

Based on this, the embodiments of the present disclosure propose a source driver, a display driver chip, a liquid crystal display device and a driving method, so that in the screen-off display mode, the judgment results of different color pixel data are obtained through an additional circuit, and then the original invalid driving channel circuit is reused to turn off the pixel drive with some zero data, so as to achieve efficient data display and save power consumption without affecting the display effect.

FIG4 is a schematic diagram of the structure of a source driver provided in an embodiment of the present disclosure, FIG5 is a schematic diagram of the structure of a driving channel in the source driver shown in FIG4 , and FIG6 is a schematic diagram of a picture occupying 50% in a screen-off display mode in a specific embodiment.

Referring to FIG4 , the embodiment of the present disclosure provides a source driver 110 for driving a display panel 101. The source driver 110 includes a plurality of driving channels, each of which provides a driving voltage to at least one column of pixels of the display panel 101 through an output buffer OP. Furthermore, the plurality of pixels are arranged in a matrix of m rows and n columns. Each pixel includes a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B.

The source driver 110 further includes a driving controller COL, an input end of which is connected to the input ends of the plurality of driving channels, for receiving pixel data of the at least one column of pixels (such as A[10:0], A[21:11], A[32:22], B[10:0], B[21:11], B[32:22], C[10:0], C[21:11] and C[32:22] in FIG. 5 ) in an off-screen display mode (AOD), and generating a driving enable signal OP Enable when the level of the pixel data of the at least one column of pixels reaches a preset condition.

The source driver 110 provides the drive enable signal OP Enable to the output buffer OP by multiplexing the invalid drive channel between the output end of the drive controller COL and the output buffer OP, and enables the connection path between the output buffer OP and the at least one column of pixels to be disconnected.

The source driver 110 of the disclosed embodiment judges the pixel data Data, and when certain preset conditions are met, generates a drive enable signal OP Enable through the level state logic of the specific pixel data data to turn off the output buffer (Source OP) OP, so as to achieve the purpose of reducing power consumption in the screen-off display mode.

In some embodiments, the preset condition is that the levels of the pixel data of the at least one column of pixels are all in a zero potential state.

In some embodiments, each driving channel may include at least: a plurality of buffers (LATCH, hereinafter referred to as L1 or L2), a plurality of first selection switches SW1-SW9, a level shifter (LS) LS, and a digital-to-analog converter PD.

The plurality of buffers receive and store the pixel data of the at least one column of pixels through the input end of the source driver 110. In one embodiment, the plurality of buffers include: a plurality of first buffers L1 and a plurality of second buffers L2. The plurality of first buffers L1 receive and store the pixel data of the at least one column of pixels through the input end of the source driver 110. The plurality of second buffers L2 are respectively connected between a first buffer L1 and a first selection switch SW1-SW9. The specific connection relationship is shown in FIG. 5. The plurality of first selection switches SW1-SW9 are connected to the plurality of first buffers L1 and the plurality of second buffers L2. The input end of SW9 is respectively connected to a second buffer L2, the input end of the level converter LS is commonly connected to the output ends of the multiple first selection switches SW1-SW9, and is used to receive the pixel data of the selected output and output the pixel data after level conversion. The input end of the digital-to-analog converter PD is connected to the output end of the level converter LS, and is used to select the corresponding level of grayscale voltage output according to the pixel data. The input end of the output buffer OP is connected to the output end of the digital-to-analog converter PD, and is used to drive each data line to a driving voltage corresponding to the grayscale voltage.

In some embodiments, the output buffer OP comprises an operational amplifier.

In some embodiments, each drive channel may further include: an output switch S1 and at least one invalid drive channel, wherein the output switch S1 is connected between the output end of the output buffer OP and ground, and the output end of the invalid drive channel is connected to the control end of the output switch S1.

In some embodiments, the invalid drive channel may include a first buffer L1, a second buffer L2 and a level converter LS, wherein the first buffer L1, the second buffer L2 and the level converter LS are connected in series between the drive controller COL and the output buffer OP in sequence, and the output end of the level converter LS is also connected to the control end of the output switch S1.

In some embodiments, the source driver 110 further includes: a plurality of second selection switches SW21 - SW26 and a plurality of third selection switches MUX12 .

The input end of each second selection switch (such as SW21) is commonly connected to the output end of the output buffer OP, the output end of each second selection switch (such as SW21) is respectively connected to the data line corresponding to a column of pixels, each of the second selection switches (such as SW21) and each of the first selection switches (such as SW11) map the data line corresponding to a column of pixels one by one, and each of the third selection switches MUX12 is respectively connected between the output ends of the level converters LS of adjacent driving channels.

In some embodiments, the driving controller COL is, for example, a logic AND gate, which digitally sends the 1-bit result of A[32:0]or B[32:0]or C[32:0] to the driving controller COL. Only when all input signals (in this embodiment, the pixel data of at least one column of pixels) are in a low level state, that is, A[32:0]or B[32:0]or C[32:0] are all data in a V0 level state, a high level driving enable signal OP Enable is output. The driving enable signal OP Enable is used to indicate to stop the working state of the output buffer OP and clamp its output terminal potential in a GND state. The driving controller COL loads this bit signal by reusing the shift register circuit that originally transmits data, and transmits the driving enable signal OP Enable to the control end of the output buffer OP and the output switch S1, so that the output buffer OP corresponding to the V0 level state outputs GND to replace, and the output buffer OP corresponding to the V255 level state outputs AVDD to replace, so as to achieve the purpose of saving power consumption.

As shown in FIG6 , the picture selects half black as an example (the more black part, the more obvious the power saving effect). The source driver of the structure in this embodiment is not adopted in the prior art, and its original rated current (Source 1Frame) is: 544uA (240*1.8uA+112uA=544uA), while the rated current (Source 1Frame) obtained by optimizing the source driver 110 of this embodiment after experiment is: 328uA (120*1.8uA+112uA=328uA), the current is optimized to 216uA, and the optimization ratio is 216/544=40%, so that efficient data display is achieved, and the purpose of saving power consumption is achieved without affecting the display effect.

Based on the same inventive concept, on the other hand, the present disclosure further provides a display driver chip, which includes the source driver 110 as described in the above embodiments.

Based on the same inventive concept, on the other hand, an embodiment of the present disclosure provides a display device, which is understood in conjunction with FIG. 1 and FIG. 2 , wherein the display device may include, for example:

Display panel 101; and

The source driver 110 as mentioned above is used to drive the display panel 101 .

In some embodiments, the display device may include one or a combination of a mobile phone, a tablet computer, a laptop computer, a desktop computer, a television, and a car display.

In some embodiments, the display panel 101 includes but is not limited to: a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light emitting diode display panel, an organic light emitting diode display panel, a quantum dot display panel, a Mirco-LED display panel, a Mini-LED display panel, a field emission display panel, a plasma display panel, an electrophoretic display panel or an electrowetting display panel.

Based on the same inventive concept, on the other hand, the present disclosure further provides a driving method applied to the aforementioned source driver 110, wherein the source driver 110 is used to drive a display panel, and includes a plurality of driving channels, each driving channel providing a driving voltage to at least one column of pixels of the display panel through an output buffer OP, as shown in FIG. 7 , wherein the driving method includes:

S110: In the screen-off display mode, pixel data of at least one column of pixels is received by a driving controller, and a driving enable signal is generated when a level of the pixel data of the at least one column of pixels reaches a preset condition.

S120: providing the drive enable signal to the output buffer by multiplexing the invalid drive channel between the output end of the drive controller and the output buffer, and enabling control of disconnection of the connection path between the output buffer and the at least one column of pixels.

In some embodiments, the preset condition is that the levels of the pixel data of the at least one column of pixels are all in a zero potential state.

In summary, the embodiments of the present disclosure provide a source driver 110, a liquid crystal display device, and a driving method, wherein the source driver 110 receives pixel data of at least one column of pixels through the driving controller COL in the off-screen display mode, and generates a driving enable signal OPEnable when the level of the pixel data of at least one column of pixels reaches a preset condition, and provides the driving enable signal OP Enable to the output buffer OP by reusing the invalid driving channel between the output end of the driving controller COL and the output buffer OP, and enables the connection path between the output buffer OP and the at least one column of pixels to be disconnected. In this way, in the off-screen display mode, the judgment results of pixel data of different colors are obtained through the additional circuit, and then the original invalid driving channel circuit is reused to turn off the pixel drive with some data being zero, so as to achieve efficient data display and save power without affecting the display effect.

It should be noted that in the description of the present disclosure, it needs to be understood that the terms "upper", "lower", "inner" and the like indicating orientation or positional relationship are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

In addition, in this article, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly illustrating the present disclosure, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present disclosure.

Claims (13)

1. A source driver for driving a display panel, comprising a plurality of drive channels, each drive channel providing a drive voltage to at least one column of pixels of the display panel through an output buffer, wherein the source driver further comprises: a driving controller, wherein an input end of the driving controller is connected to input ends of the plurality of driving channels, and is used to receive pixel data of the at least one column of pixels in an off-screen display mode, and to generate a driving enable signal when a level of the pixel data of the at least one column of pixels reaches a preset condition, The source driver provides the drive enable signal to the output buffer by multiplexing the invalid drive channel between the output end of the drive controller and the output buffer, and enables the connection path between the output buffer and the at least one column of pixels to be disconnected. 2. The source driver according to claim 1, wherein the preset condition is: The pixel data of the at least one column of pixels are all at a zero potential state. 3. The source driver according to claim 2, wherein each driving channel comprises: a plurality of buffers, wherein the plurality of buffers receive and store pixel data of the at least one column of pixels through an input terminal of the source driver; A plurality of first selection switches, wherein input ends of the plurality of first selection switches are respectively connected to a buffer; A level converter, the input end of which is commonly connected to the output ends of the plurality of first selection switches, for receiving the pixel data output by the strobe, and performing level conversion on the pixel data before outputting it; A digital-to-analog converter, the input end of which is connected to the output end of the level converter, and is used to select a grayscale voltage output of a corresponding level according to the pixel data, The input end of the output buffer is connected to the output end of the digital-to-analog converter, and is used to drive each data line to a driving voltage corresponding to the grayscale voltage. 4. The source driver according to claim 3, wherein the plurality of buffers comprises: a plurality of first buffers, wherein the plurality of first buffers receive and store pixel data of the at least one column of pixels through an input terminal of the source driver; A plurality of second buffers are respectively connected between a first buffer and a first selection switch. 5 . The source driver according to claim 4 , wherein the output buffer comprises an operational amplifier. 6. The source driver according to claim 5, wherein each driving channel further comprises: an output switch connected between an output terminal of the output buffer and ground; At least one invalid driving channel, the output end of the invalid driving channel is connected to the control end of the output switch. 7. The source driver according to claim 6, wherein the invalid driving channel comprises a first buffer, a second buffer and a level converter, The first buffer, the second buffer and the level converter are sequentially connected in series between the driving controller and the output buffer, and the output end of the level converter is also connected to the control end of the output switch. 8. The source driver according to claim 7, further comprising: a plurality of second selection switches, wherein the input end of each second selection switch is commonly connected to the output end of the output buffer, the output end of each second selection switch is respectively connected to the data line corresponding to a column of pixels, and each second selection switch and each first selection switch are mapped one by one to the data line corresponding to a column of pixels; and A plurality of third selection switches, each of the third selection switches is respectively connected between output terminals of the level converters of adjacent driving channels. 9. A display driver chip, comprising the source driver according to any one of claims 1 to 8. 10. A display device, comprising: display panel; and The source driver according to any one of claims 1 to 8, used to drive the display panel. 11 . The display device according to claim 10 , wherein the display device comprises one or a combination of a mobile phone, a tablet computer, a laptop computer, a desktop computer, a television, and a car display. 12. A driving method for the source driver according to claim 1, wherein the source driver is used to drive a display panel, and comprises a plurality of driving channels, each driving channel providing a driving voltage to at least one column of pixels of the display panel through an output buffer, wherein the driving method comprises: In the screen-off display mode, the driving controller is used to receive pixel data of at least one column of pixels, and a driving enable signal is generated when the level of the pixel data of the at least one column of pixels reaches a preset condition; By multiplexing the invalid driving channel between the output end of the driving controller and the output buffer, the driving enable signal is provided to the output buffer, and the connecting path between the output buffer and the at least one column of pixels can be controlled to be disconnected. 13 . The driving method according to claim 12 , wherein the preset condition is that the levels of the pixel data of the at least one column of pixels are all in a zero potential state.