WO2021134832A1

WO2021134832A1 - Display panel driving method, display driving circuit, and display panel

Info

Publication number: WO2021134832A1
Application number: PCT/CN2020/071904
Authority: WO
Inventors: 赵隋鑫
Original assignee: 深圳市华星光电半导体显示技术有限公司
Priority date: 2019-12-31
Filing date: 2020-01-14
Publication date: 2021-07-08
Also published as: CN110992897B; CN110992897A

Abstract

A display panel driving method, a display driving circuit, and a display panel. The method comprises: when it is detected that a display panel completes the current display, writing a reset voltage (Vpre) to each reset line corresponding to a scan driving circuit (21) in a driving circuit to reset the source of each driving TFT in the driving circuit. The reset voltage (Vpre) decreases as the distance between each reset line and the corresponding scan driving circuit (21) increases, corresponding reset voltages (Vpre) are written to the reset lines from near to far with respect to the scan driving circuit (21), and the reset voltages (Vpre) decrease correspondingly with the increase of the distances. The methods in which the same reset voltage (Vpre) is input for the entire driving circuit in the traditional technology are changed into reducing the written reset voltage (Vpre) with the increase of the distance between the reset lines and the scan driving circuit (21), such that the voltages of the sources of driving TFTs at different positions on the driving circuit are consistent, thereby improving the display uniformity of the panel.

Description

Display panel driving method, display driving circuit and display panel

Technical field

The present application relates to the field of panel display driving technology, and in particular to a display panel driving method, a display driving circuit and a display panel.

Background technique

With the development of display technology, display panels have become more and more widely used. During the display process of the display panel, data (Data) and reset voltage (Vpre) must be written at the same time. In order to ensure the display uniformity of the display panel, each position of the display panel The gate voltage (Vg) must reach more than 96% of the set value of the data voltage. However, in the display process of the display panel, the control of the source voltage (Vs) is usually ignored, but due to the source voltage (Vs) It is susceptible to the influence of factors such as the feedthrough formed when the gate is turned off, resulting in large differences in the source voltage (Vs) of different positions on the display panel, which will seriously affect the driving TFT (Thin Film Transistor (thin film transistor) voltage between the gate and source.

technical problem

During the implementation process, the inventor found that the traditional technology has at least the following problem: the traditional display panel displays unevenly.

Technical solutions

Based on this, it is necessary to provide a display panel driving method, a display driving circuit, and a display panel in response to the uneven display of the traditional display panel.

In order to achieve the foregoing objective, on the one hand, an embodiment of the present application provides a display panel driving method, which includes the following steps:

When it is detected that the display panel has completed the current display, the reset voltage is written to each reset circuit corresponding to the scan driving circuit in the driving circuit to reset the source of the driving TFT in the driving circuit; the reset voltage follows the reset circuit The distance from the corresponding scan driving circuit increases and decreases accordingly.

On the other hand, an embodiment of the present application also provides a display driving circuit, including a driving circuit and an IC circuit;

The IC circuit is used to write reset voltages to the reset lines corresponding to the scan driving circuit in the driving circuit when detecting that the display panel has completed the current display, so as to reset the source of the driving TFT in the driving circuit; reset voltage As the distance between the reset line and the corresponding scan driving circuit increases, it decreases accordingly.

In another aspect, an embodiment of the present application also provides a display panel including a display driving circuit; the display driving circuit includes a driving circuit and an IC circuit;

Beneficial effect

The display panel driving method provided by each embodiment of the present application passes the following steps: when the display panel is detected to complete the current display, the reset voltage is written to each reset line corresponding to the scan driving circuit in the driving circuit, so as to The source of the driving TFT is reset, where the reset voltage decreases as the distance between the reset line and the corresponding scan driving circuit increases, and the reset line is written to the reset line from the closest to the farthest distance from the scan driving circuit. Corresponding reset voltage, and the reset voltage decreases correspondingly with the increase of the distance, which changes the way of inputting the same reset voltage for the entire drive circuit in the traditional technology, and realizes that the distance between the reset line and the scan drive circuit is changed. The influence of feedthrough caused by increasing and closing the gate of the driving TFT is reduced, and the written reset voltage is reduced, so that the source voltage of the driving TFT at different positions on the driving circuit is consistent, thereby improving the display uniformity of the panel.

Description of the drawings

FIG. 1 is a flowchart of steps of a method for driving a display panel in an embodiment;

Figure 2 is a layout diagram of a scan driving circuit in an embodiment;

Fig. 3 is a layout diagram of a scan driving circuit in another embodiment;

FIG. 4 is a schematic structural diagram of a 3T1C type pixel driving circuit in an embodiment;

FIG. 5 is a schematic diagram of the structure of a display driving circuit in an embodiment.

Embodiments of the present invention

In order to facilitate the understanding of the application, the application will be described in a more comprehensive manner with reference to the relevant drawings. The preferred embodiment of the application is shown in the accompanying drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to and integrated with another element, or there may be a centering element at the same time. The terms "installed", "one end", "the other end" and similar expressions used herein are for illustrative purposes only.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of this application. The terms used in the specification of the application herein are only for the purpose of describing specific embodiments, and are not intended to limit the application. The term "and/or" as used herein includes any and all combinations of one or more related listed items.

In order to solve the problem of uneven display of traditional display panels, in one embodiment, as shown in FIG. 1, a display panel driving method is provided, which includes the following steps:

Step S110, when it is detected that the display panel has completed the current display, the reset voltage is written to each reset line corresponding to the scan driving circuit in the driving circuit, so as to reset the source of the driving TFT in the driving circuit; As the distance between the reset line and the corresponding scan drive circuit increases, it decreases accordingly.

It should be noted that after each display of the display panel is completed, the source of the driving TFT in the driving circuit of the display panel needs to be reset, so as to ensure the display quality of each display. IC (integrated circuit, integrated circuit) after detecting the completion of the current display of the display panel, the circuit sends the reset circuit (pre line) Write the corresponding reset voltage (Vpre) respectively.

For the scan driving circuit on the driving circuit of the display panel, the scan driving circuit can be arranged on one side of the driving circuit or on opposite sides of the driving circuit. In one example, as shown in FIG. 2, the scan driving circuit 21 Set only on one side of the drive circuit 23, and set the reset voltage corresponding to the write according to the distance between the reset line 25 (the reset line 25 is connected to the data drive circuit 27) and the corresponding scan drive circuit 21, and the distance corresponding to the scan drive circuit 21 The farther the reset circuit 25 is, the less it is affected by the feedthrough (Feedthrough) caused by the gate of the driving TFT is turned off, and the reset voltage corresponding to the write is relatively smaller. Among them, the value of the reset voltage and the gate resistor capacitance of the driving TFT (Gate RC, in the pixel circuit, the voltage signal needs to pass through different sizes of capacitors and resistor circuits to different positions on the panel, and the larger the capacitor resistance, the signal transmission The more obvious the hysteresis effect is, it will increase the turn-on and turn-off time of the driving TFT switch, and slow down the speed of turning off from high voltage to low voltage). It must meet the requirement of preventing the OLED device from turning on. Specifically, the difference can be determined by simulation technology. The magnitude of the reset voltage written by the reset circuit. In an example, the reset voltage ranges from 1 volt to 1.5 volts. For example, the reset line of the nearest scan driver circuit writes a reset voltage of 1.5 volts, and the reset line of the scan driver circuit farthest away from the reset line writes. 1 volt reset voltage. Among them, the feed-through phenomenon refers to the parasitic capacitance between the gate metal and the source metal of the driving TFT. At the moment of its switching, the gate voltage quickly drops from a high potential to a low potential. The gate voltage will change according to the principle of conservation of charge. .

In another example, the scan drive circuit is arranged on two opposite sides of the drive circuit, the scan drive circuits on both sides respectively affect the reset line on the drive circuit, and the scan drive circuits on both sides have more influence on the reset line that is closer to the drive circuit. Therefore, the reset line on the driving circuit is divided into two parts according to the distance to the scan driving circuit. One part is mainly affected by the scan driving circuit on one side, and the other part is mainly affected by the scan driving circuit on the other side. Specifically, as shown in FIG. 3, the scan driving circuit 21 includes a first side scan driving circuit 211 and a second side scan driving circuit 213; the first side scan driving circuit 211 and the second side scan driving circuit 213 are provided in the driving circuit 23. On the opposite side ends; the reset line 25 whose distance to the first side scan drive circuit 211 is less than the distance to the second side scan drive circuit 213 corresponds to the first side scan drive circuit 211; to the first side scan drive circuit 211 The reset line 25 whose distance is greater than or equal to the distance to the second side scan drive circuit 213 corresponds to the second side scan drive circuit 213, that is, all the reset lines 25 between the scan drive circuits on both sides are allocated in half to the first side scan drive circuit The reset line whose distance 211 is less than the distance to the second side scan driver circuit 213, refer to the first side scan driver circuit 211 when writing the reset voltage; the distance to the first side scan driver circuit 211 is greater than or equal to the second side scan The reset line 25 of the distance of the driving circuit 213 refers to the second side scan driving circuit 213 when writing the reset voltage.

Relative to the reset line of the scan driver circuit on the first side, as the distance from the scan driver circuit on the first side increases, the written reset voltage decreases accordingly; the reset line of the scan driver circuit on the second side decreases accordingly. As the distance from the second-side scan driving circuit increases, the reset voltage to be written decreases accordingly.

The display panel driving method of the present application can be applied to but not limited to: 3T1C type pixel driving circuit, 4T2C type pixel driving circuit, 5T2C type pixel driving circuit or 6T1C type pixel driving circuit. Take 3T1C type pixel drive circuit (as shown in Figure 4) as an example: 3T1C type pixel drive circuit includes scanning TFT (ie Gate TFT in Figure 4), drive TFT (ie Drive TFT in Figure 4), sensing TFT (Sen TFT in Figure 4) and capacitance (Cgs in Figure 4); the gate of the scanning TFT is connected to the scanning circuit (Scan in Figure 4), and the drain is connected to the data circuit (Data in Figure 4) ), the source is connected to the gate of the driving TFT and one end of the capacitor; the drain of the driving TFT is connected to an external voltage source (ie VDD in Figure 4), and the source is connected to the other end of the capacitor, the source of the sensing TFT and the OLED Device; the gate of the sensing TFT is connected to the control circuit (ie Sense in Figure 4), the drain is connected to the reset circuit (ie, Pre in Figure 4), and the source is connected to the other end of the capacitor, the source of the sensing TFT and OLED device.

In the embodiment of the display panel driving method of the present application, when it is detected that the display panel has completed the current display, the reset voltage is written to each reset line corresponding to the scan driving circuit in the driving circuit, so as to write the reset voltage to the driving TFT in the driving circuit. The source is reset, where the reset voltage decreases as the distance between the reset circuit and the corresponding scan driver circuit increases, and the corresponding reset voltage is written to the reset circuit from the closest to the farthest distance from the scan driver circuit. , And the reset voltage decreases correspondingly with the increase of the distance, which changes the way of inputting the same reset voltage for the entire driving circuit in the traditional technology, and realizes that the distance between the reset line and the scan driving circuit increases, so that the driving The feedthrough effect caused by the TFT gate closed is reduced, and the written reset voltage is reduced, so that the source voltages of the driving TFTs at different positions on the driving circuit are consistent, and the display uniformity of the panel is improved.

In one embodiment, in order to avoid the large reset workload and low efficiency caused by the setting of different reset voltages for each reset line, the area occupied by each reset line corresponding to the scan drive circuit is moved away from the scan edge. The direction of the driving circuit is sequentially divided into a first area, a second area, and a third area. Among them, the reset lines corresponding to the scan driving circuit refer to the reset lines that are mainly affected by the scan circuit.

In an example, when the scan driving circuit is only arranged on one side of the driving circuit, the entire driving circuit is sequentially divided into a first area, a second area, and a third area in a direction away from the scan driving circuit.

In another example, the scan driving circuit is arranged on opposite sides of the driving circuit, and the entire driving circuit is first symmetrically divided into the first part (the opposite side of the first part) along the central axis (the central axis is parallel to the side end where the scan driving circuit is arranged). The scan driver circuit) and the second part (the second part is opposite to the scan driver circuit on the other side), the entire first part is divided into the first area, the second area and the third area in the direction away from the scan driving circuit on one side. Area, the entire second part is sequentially divided into a first area, a second area, and a third area along a direction away from the scan driving circuit on the other side.

In one example, the area sizes of the first area, the second area, and the third area are different from each other. In another example, the area sizes of the first area, the second area, and the third area are equal.

Write different reset voltages to different areas. Specifically, input the first reset voltage to each reset line in the first area; input the second reset voltage to each reset line in the second area; and input the second reset voltage to each reset line in the second area. Each reset circuit inputs a third reset voltage; the first reset voltage is greater than the second reset voltage; the second reset voltage is greater than the third reset voltage. Further, in an example, the value range of the first reset voltage is 1V to 1.5V; the value range of the second reset voltage is 1V to 1.5V; and the value range of the third reset voltage is 1V to 1.5V. 1.5 volts.

This embodiment provides a way of dividing into three regions, but does not exclude other ways of dividing regions, for example, 4 regions, 5 regions, 6 regions, and so on.

In the embodiment of the display panel driving method of the present application, the corresponding reset voltage is written by region to avoid setting the corresponding reset voltage for each reset line. It is only necessary to set the number of reset voltages according to the number of divided regions to reduce the reset The workload improves the reset efficiency, and it is also conducive to making the source voltages of the driving TFTs at different positions on the driving circuit consistent, thereby improving the display uniformity of the panel.

In one embodiment, as shown in FIG. 5, a display driving circuit is also provided, including a driving circuit 51 and an IC circuit 53;

The IC circuit 53 is used to write reset voltages to the reset lines corresponding to the scan driving circuit in the driving circuit 51 to reset the source of the driving TFT in the driving circuit 61 when it is detected that the display panel has completed the current display. ; The reset voltage decreases as the distance between the reset line and the corresponding scan drive circuit increases.

It should be noted that the IC circuit is the control center of the drive circuit and the provider of the reset voltage. After the IC circuit detects that the current display of the display panel is completed, it writes the corresponding reset voltages to the reset lines in the drive circuit. In an example, the scan drive circuit is only arranged on one side of the drive circuit, and the IC circuit increases according to the distance from the reset line to the corresponding scan drive circuit, while reducing the written reset voltage. Specifically, the value range of the reset voltage It is 1 volt to 1.5 volts.

In another example, the scan driving circuit is arranged on opposite sides of the driving circuit, the scan driving circuit includes a first side scan driving circuit and a second side scan driving circuit; the first side scan driving circuit and the second side scan driving circuit Set on the opposite sides of the drive circuit; the reset line whose distance to the first side scan drive circuit is smaller than the distance to the first side scan drive circuit corresponds to the first side scan drive circuit; the distance to the first side scan drive circuit The reset line that is greater than or equal to the distance from the first side scan driving circuit corresponds to the second side scan driving circuit. The reset voltage written by the IC circuit to the reset line of the scan driver circuit on the first side decreases as the distance between the reset line and the scan driver circuit on the first side increases; the IC circuit scans the driver circuit toward the second side. The reset voltage written by the reset line of the reset line decreases as the distance between the reset line and the second-side scan driving circuit increases.

In one embodiment, in order to avoid the large reset workload and low efficiency caused by the setting of different reset voltages for each reset line, the area occupied by each reset line corresponding to the scan drive circuit is moved away from the scan edge. The direction of the drive circuit is sequentially divided into a first area, a second area, and a third area. Correspondingly, the IC circuit includes: a first output unit, a second output unit, and a third output unit. The first output unit is used to Each reset line in the first area inputs the first reset voltage; the second output unit is used to input the second reset voltage to each reset line in the second area; the third output unit is used to input the reset lines in the third area Input the third reset voltage; the first reset voltage is greater than the second reset voltage; the second reset voltage is greater than the third reset voltage.

Further, in an example, the value range of the first reset voltage is 1V to 1.5V; the value range of the second reset voltage is 1V to 1.5V; and the value range of the third reset voltage is 1V to 1.5V. 1.5 volts.

In each embodiment of the display driving circuit of the present application, during the process of driving the display panel to display, the display driving circuit controls the voltage of the driving TFT source at each position to ensure consistency, which improves the display uniformity of the display panel.

In one embodiment, a display panel is also provided, including the display driving circuit described in the embodiments of the display driving circuit of the present application.

It should be noted that the display drive circuit in this embodiment is the same as the display drive circuit described in each embodiment of the display drive circuit of this application. For detailed description, please refer to the content of each embodiment of the display drive circuit of this application, and will not be repeated here. .

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, All should be considered as the scope of this specification.

The above-mentioned embodiments only express several implementation manners of the present application, and their description is relatively specific and detailed, but they should not be interpreted as a limitation on the scope of the patent application. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can be made, and these all fall within the protection scope of this application. Therefore, the scope of protection of the patent of this application shall be subject to the appended claims.

Claims

A method for driving a display panel, which includes the following steps:

When it is detected that the display panel has completed the current display, a reset voltage is written to each reset line corresponding to the scan driving circuit in the driving circuit to reset the source of the driving TFT in the driving circuit; the reset voltage As the distance between the reset line and the corresponding scan driving circuit increases, it decreases accordingly.
The display panel driving method according to claim 1, wherein:

Input a first reset voltage to each reset line in the first area; input a second reset voltage to each reset line in the second area; input a third reset voltage to each reset line in the third area;

The first area, the second area, and the third area are obtained by sequentially dividing the area occupied by the reset lines corresponding to the scan driving circuit in a direction away from the scan driving circuit; The first reset voltage is greater than the second reset voltage; the second reset voltage is greater than the third reset voltage.
3. The display panel driving method according to claim 2, wherein the area sizes of the first area, the second area, and the third area are equal.
3. The display panel driving method according to claim 2, wherein the value range of the first reset voltage is 1V to 1.5V; the value range of the second reset voltage is 1V to 1.5V; the The value range of the third reset voltage is 1V to 1.5V.
The display panel driving method according to claim 1, wherein the scan driving circuit includes a first side scan driving circuit and a second side scan driving circuit; the first side scan driving circuit and the second side scan driving circuit The circuit is arranged on opposite sides of the driving circuit;

The reset line whose distance to the first side scan drive circuit is less than the distance to the second side scan drive circuit corresponds to the first side scan drive circuit;

The reset line whose distance to the first side scan drive circuit is greater than or equal to the distance to the second side scan drive circuit corresponds to the second side scan drive circuit.
4. The display panel driving method according to claim 1, wherein the reset voltage has a value range of 1V to 1.5V.
A display driving circuit, which includes a driving circuit and an IC circuit;

The IC circuit is used to, when detecting that the display panel has completed the current display, write reset voltages to the respective reset lines corresponding to the scan driving circuit in the driving circuit, so as to write the reset voltage to the source of the driving TFT in the driving circuit. The reset voltage is reset; the reset voltage decreases as the distance between the reset line and the corresponding scan drive circuit increases.
8. The display driving circuit according to claim 7, wherein the IC circuit comprises:

A first output unit, where the first output unit is used to input a first reset voltage to each reset line in the first area;

A second output unit, where the second output unit is used to input a second reset voltage to each reset line in the second area;

A third output unit, the third output unit is used to input a third reset voltage to each reset line in the third area;

Wherein, the first area, the second area, and the third area are the areas occupied by the reset lines corresponding to the scan drive circuit, and are sequentially divided along the distance from the scan drive circuit. Obtain; the first reset voltage is greater than the second reset voltage; the second reset voltage is greater than the third reset voltage.
7. The display drive circuit according to claim 7, wherein the scan drive circuit comprises a first side scan drive circuit and a second side scan drive circuit; the first side scan drive circuit and the second side scan drive circuit Arranged on opposite sides of the drive circuit;

The reset line whose distance to the first side scan drive circuit is less than the distance to the first side scan drive circuit corresponds to the first side scan drive circuit;

The reset line whose distance to the first side scan drive circuit is greater than or equal to the distance to the first side scan drive circuit corresponds to the second side scan drive circuit.
8. The display drive circuit according to claim 8, wherein the scan drive circuit comprises a first side scan drive circuit and a second side scan drive circuit; the first side scan drive circuit and the second side scan drive circuit Arranged on opposite sides of the drive circuit;

The reset line whose distance to the first side scan drive circuit is less than the distance to the first side scan drive circuit corresponds to the first side scan drive circuit;

The reset line whose distance to the first side scan drive circuit is greater than or equal to the distance to the first side scan drive circuit corresponds to the second side scan drive circuit.
A display panel, which includes a display drive circuit; the display drive circuit includes a drive circuit and an IC circuit;

The IC circuit is used to write reset voltages to the reset lines corresponding to the scan driving circuit in the driving circuit when detecting that the display panel has completed the current display, so as to write the reset voltage to the source of the driving TFT in the driving circuit. The reset voltage is reset; the reset voltage decreases as the distance between the reset line and the corresponding scan drive circuit increases.
The display panel according to claim 11, wherein the IC circuit comprises:

A first output unit, where the first output unit is used to input a first reset voltage to each reset line in the first area;

A second output unit, where the second output unit is used to input a second reset voltage to each reset line in the second area;

A third output unit, the third output unit is used to input a third reset voltage to each reset line in the third area;

Wherein, the first area, the second area, and the third area are the areas occupied by the reset lines corresponding to the scan drive circuit, and are sequentially divided along the distance from the scan drive circuit. Obtain; the first reset voltage is greater than the second reset voltage; the second reset voltage is greater than the third reset voltage.
11. The display panel according to claim 11, wherein the scan driving circuit comprises a first side scan driving circuit and a second side scan driving circuit; the first side scan driving circuit and the second side scan driving circuit are arranged On opposite sides of the drive circuit;

The reset line whose distance to the first side scan drive circuit is less than the distance to the first side scan drive circuit corresponds to the first side scan drive circuit;

The reset line whose distance to the first side scan drive circuit is greater than or equal to the distance to the first side scan drive circuit corresponds to the second side scan drive circuit.
The display panel according to claim 12, wherein the scan driving circuit comprises a first side scan driving circuit and a second side scan driving circuit; the first side scan driving circuit and the second side scan driving circuit are arranged On opposite sides of the drive circuit;

The reset line whose distance to the first side scan drive circuit is less than the distance to the first side scan drive circuit corresponds to the first side scan drive circuit;

The reset line whose distance to the first side scan drive circuit is greater than or equal to the distance to the first side scan drive circuit corresponds to the second side scan drive circuit.