This application claims priority to Chinese Patent Application No. 202311227414.3, filed on Sep. 21, 2023, and entitled “PIXEL DRIVING CIRCUIT, DRIVING METHOD FOR PIXEL DRIVING CIRCUIT, AND DISPLAY PANEL”. The entire disclosures of the above application are incorporated herein by reference.
The present disclosure relates to the field of display technologies, and in particular to a pixel driving circuit, a driving method for the pixel driving circuit, and a display panel.
In existing pixel driving circuits, most transistors use low-temperature polysilicon thin film transistors or oxide thin film transistors. Compared with general amorphous silicon thin film transistors, the low-temperature polysilicon thin film transistors and the oxide thin film transistors have higher mobility and more stable characteristics, and are more suitable for configuration in active matrix organic light-emitting diode displays.
However, due to the limitations of a crystallization process, the low-temperature polysilicon thin film transistors fabricated on large-area glass substrates often have non-uniformity in electrical parameters such as threshold voltage and mobility. This non-uniformity will be converted into differences in driving current and brightness of organic light-emitting diode devices, and will be perceived by human eyes as color unevenness. Although the oxide thin film transistors have better process uniformity, they are similar to the amorphous silicon thin film transistors, under long-term pressure and high temperature, due to a gate voltage, part of the negative charges in a channel layer are captured into an interface between the channel layer and a gate insulating layer or directly into the gate insulating layer. As a result, part of the gate voltage is shielded, causing a threshold voltage to drift and causing poor display problems.
Accordingly, it is necessary to provide a pixel driving circuit, a driving method for the pixel driving circuit, and a display panel to improve this issue.
Embodiments of the present disclosure provide a pixel driving circuit, a driving method for the pixel driving circuit, and a display panel, which can prevent a threshold voltage from drifting significantly due to long-term pressurization, thereby solving the problem of poor display caused by the drifting of the threshold voltage.
An embodiment of the present disclosure provides a pixel driving circuit, including:
In any one frame period, one of the first gate and the second gate is controlled by a data signal output by the data signal terminal to turn on the driving transistor; and in a plurality of frame periods, the first gate and the second gate are alternately controlled by the data signal to turn on the driving transistor.
According to one embodiment of the present disclosure, the writing module includes:
According to one embodiment of the present disclosure, the first scan signal terminal outputs a first scan signal, the second scan signal terminal outputs a second scan signal, a driving time sequence of the pixel driving circuit includes a data writing stage and a data clearing stage, and the driving time sequence of the pixel driving circuit includes a first driving time sequence and a second driving time sequence;
According to one embodiment of the present disclosure, the pixel driving circuit further includes a storage module, where the storage module is electrically connected to the first node, the second node, and the third node, and the storage module is configured to store and maintain a threshold voltage of the driving transistor.
According to one embodiment of the present disclosure, the storage module includes:
According to one embodiment of the present disclosure, the pixel driving circuit further includes a reset module, and the reset module includes:
According to one embodiment of the present disclosure, the pixel driving circuit further includes a light-emitting control module, and the light-emitting control module includes a fourth transistor, a gate of the fourth transistor is electrically connected to a fourth scan signal terminal, a source of the fourth transistor is electrically connected to the first power signal terminal, and a drain of the fourth transistor is electrically connected to the source of the driving transistor.
An embodiment of the present disclosure also provides a driving method for driving the above-mentioned pixel driving circuit. A driving time sequence of the driving method includes:
In any one frame period, one of the first gate and the second gate is controlled by the data signal to turn on the driving transistor; and in a plurality of frame periods, the first gate and the second gate are alternately controlled by the data signal to turn on the driving transistor.
According to one embodiment of the present disclosure, the driving time sequence of the driving method includes a first driving time sequence and a second driving time sequence;
According to one embodiment of the present disclosure, the writing module includes:
According to one embodiment of the present disclosure, the pixel driving circuit further includes a storage module, the storage module is electrically connected to the first node, the second node, and the third node, and the storage module is configured to store and maintain a threshold voltage of the driving transistor.
According to one embodiment of the present disclosure, the storage module includes:
According to one embodiment of the present disclosure, the pixel driving circuit further includes a reset module, and the reset module includes:
According to one embodiment of the present disclosure, the pixel driving circuit further includes a light-emitting control module, the light-emitting control module includes a fourth transistor, a gate of the fourth transistor is electrically connected to a fourth scan signal terminal, a source of the fourth transistor is electrically connected to the first power signal terminal, and a drain of the fourth transistor is electrically connected to the source of the driving transistor.
An embodiment of the present disclosure also provides a display panel including the above-mentioned pixel driving circuit. The pixel driving circuit includes:
In any one frame period, one of the first gate and the second gate is controlled by a data signal output by the data signal terminal to turn on the driving transistor; and in a plurality of frame periods, the first gate and the second gate are alternately controlled by the data signal to turn on the driving transistor.
According to one embodiment of the present disclosure, the writing module includes:
According to one embodiment of the present disclosure, the first scan signal terminal outputs a first scan signal, the second scan signal terminal outputs a second scan signal, a driving time sequence of the pixel driving circuit includes a data writing stage and a data clearing stage, and the driving time sequence of the pixel driving circuit includes a first driving time sequence and a second driving time sequence;
According to one embodiment of the present disclosure, the pixel driving circuit further includes a storage module, the storage module is electrically connected to the first node, the second node, and the third node, and the storage module is configured to store and maintain a threshold voltage of the driving transistor.
According to one embodiment of the present disclosure, the storage module includes:
According to one embodiment of the present disclosure, the pixel driving circuit further includes a reset module, and the reset module includes:
Advantages of the embodiments of the present disclosure are as follows. The embodiments of the present disclosure provide the pixel driving circuit, the driving method for the pixel driving circuit, and the display panel. The pixel driving circuit includes the writing module, the driving transistor, and the light-emitting element. The writing module is electrically connected to the data signal terminal, and is electrically connected to the first node and the second node. The writing module is configured to connect the data signal terminal to the first node and the second node, or to disconnect the data signal terminal from the first node and the second node. The driving transistor is the double-gate transistor. The first gate of the driving transistor is electrically connected to the first node. The second gate of the driving transistor is electrically connected to the second node. The source of the driving transistor is electrically connected to the first power signal terminal. The drain of the driving transistor is electrically connected to the third node. The driving transistor is configured to connect the first power signal terminal and the third node, or to disconnect the first power signal terminal and the third node. The light-emitting element is electrically connected to the second power signal terminal and electrically connected to the third node. In any one frame period, one of the first gate and the second gate is controlled by the data signal to turn on the driving transistor. Moreover, in the plurality of frame periods, the first gate and the second gate are alternately controlled by the data signal to turn on the driving transistor. It can prevent long-term voltage application to the same gate from causing some negative electrons in a channel layer to be captured into an interface between the channel layer and a gate insulating layer or directly into the gate insulating layer under the action of a gate voltage. Therefore, it can prevent the threshold voltage from drifting significantly due to long-term voltage application, thereby solving the problem of poor display caused by the drifting of the threshold voltage.
The following description of the embodiments refers to the accompanying drawings to illustrate specific embodiments in which the present disclosure may be implemented. Directional terms, such as upper, lower, front, back, left, right, inner, outer, side, etc., mentioned in the present disclosure only refer to directions of the accompanying drawings. Therefore, the directional terms used are to illustrate and understand the present disclosure, but not to limit the present disclosure. In the drawings, units with similar structures are represented by the same numerals.
The present disclosure will be further described below with reference to the accompanying drawings and specific embodiments.
An embodiment of the present disclosure provides a pixel driving circuit that can prevent a threshold voltage from drifting significantly due to long-term voltage application, thereby solving a problem of poor display caused by the drifting of the threshold voltage.
As shown in
For example, the writing module 10 can connect the data signal terminal Data and the first node A under a control of a scan signal, so as to transmit a data signal output by the data signal terminal Data to the first node A through the data writing module 10. The writing module 10 can also disconnect the data signal terminal Data from the first node A under the control of the scan signal. At this time, the first node A cannot receive the data signal output by the data signal terminal Data. The writing module 10 can selectively connect the data signal terminal Data to one of the first node A and the second node B under the control of the scan signal, and disconnect the connection between the data signal terminal Data and the other one of the first node A and the second node B under the control of the scan signal. The writing module 10 can also disconnect the connection between the data signal terminal Data and the first node A and the connection between the data signal terminal Data and the second node B at the same time under the control of the scan signal. Alternatively, the writing module 10 can also connect the data signal terminal Data to the first node A and the second node B simultaneously under the control of the scan signal.
The driving transistor T0 is a double-gate transistor. A first gate G1 of the driving transistor T0 is electrically connected to the first node A. A second gate G2 of the driving transistor T0 is electrically connected to the second node B. A source of driving transistor T0 is electrically connected to a first power signal terminal VDD. A drain of driving transistor T0 is electrically connected to a third node S. The driving transistor T0 is configured to connect the first power signal terminal VDD and the third node S, or to disconnect the first power signal terminal VDD from the third node S. For example, the driving transistor T0 can connect the first power signal terminal VDD and the third node S under the control of the data signal, so that a first power signal output by the first power signal terminal VDD is transmitted to the third node S through the driving transistor T0. The driving transistor T0 can also disconnect the first power signal terminal VDD from the third node S under the control of the data signal.
In some embodiments of the present disclosure, the driving transistor T0 is a metal oxide semiconductor thin film transistor. A material of a semiconductor layer of the driving transistor can be selected from any one of Indium Gallium Zinc Oxide (IGZO), Indium Zinc Oxide (IZO), Indium Gallium Zinc Tin Oxide (IGZTO), etc. A film layer structure of the driving transistor T0 can refer to a film layer structure of the transistor of the existing display panel, and is not limited herewith.
The light-emitting element 11 is electrically connected to a second power signal terminal VSS and electrically connected to the third node S. When a circuit between the first power signal terminal VDD and the second power signal terminal VSS is turned on, the light-emitting element 11 emits light.
In some embodiments of the present disclosure, the light-emitting element 11 is a micro light-emitting diode (Mirco LED) chip. A size of the Micro LED chip is less than 100 micrometers. In practical applications, a type of the light-emitting element 11 is not limited to the Micro LED chip as the above embodiment, but can also be a mini light-emitting diode (Mini LED) or an organic light-emitting diode (OLED).
As shown in
In some embodiments of the present disclosure, the writing module 10 includes a first transistor T1 and a second transistor T2. A gate of the first transistor T1 is electrically connected to a first scan signal terminal WR1. A source of the first transistor T1 is electrically connected to the data signal terminal Data. A drain of the first transistor T1 is electrically connected to the first node A. A first scan signal output by the first scan signal terminal WR1 can control the turning on and off of the first transistor T1. A gate of the second transistor T2 is electrically connected to a second scan signal terminal WR2. A source of the second transistor T2 is electrically connected to the data signal terminal Data. A drain of the second transistor T2 is electrically connected to the second node B. A second scan signal output by the second scan signal terminal WR2 can control the turning on and off of the second transistor T2.
In some embodiments of the present disclosure, a driving time sequence of the pixel driving circuit includes a data writing stage and a data clearing stage. The driving time sequence of the driving circuit includes a first driving time sequence and a second driving time sequence. Both the first driving time sequence and the second driving time sequence have a complete one frame period.
As shown in
In the data writing stage of the second driving time sequence, the first scan signal is at the low potential and the second scan signal is at the high potential. The first transistor T1 is turned off under the control of the first scan signal. The second transistor T2 is turned on by the second scan signal. The second transistor T2 outputs the data signal to the second node B, and the data signal is at the high potential. The second gate G2 is controlled by the data signal to turn on the driving transistor T0 to charge the second gate G2, that is, the second node B. In the data clearing stage of the second driving time sequence, the first scan signal is at the high potential and the second scan signal is at the low potential. The first transistor T1 is turned on by the first scan signal. The second transistor T2 is turned off under the control of the second scan signal. The first transistor T1 outputs the data signal to the first node A, and the data signal is at the low potential. The first gate G1 is controlled by the data signal to turn off the driving transistor T0, so that the driving transistor is in the off-state in the data clearing stage of the second driving time sequence, thus clearing the voltage at the first gate G1, that is, the first node A.
In some embodiments of the present disclosure, in any one frame period, the pixel driving circuit is driven by one of the first driving time sequence and the second driving time sequence. In a plurality of frame periods, the pixel driving circuit is alternately driven by the first driving time sequence and the second driving time sequence. This can prevent the threshold voltage of the driving transistor from drifting significantly due to long-term pressurization, thereby solving the problem of poor display caused by the drifting of the threshold voltage.
In some embodiments of the present disclosure, the pixel driving circuit further includes a storage module 12. The storage module 12 is electrically connected to the first node A, the second node B, and the third node S. The storage module 12 is configured to store and maintain the threshold voltage of the driving transistor 10.
In one embodiment, as shown in
The driving time sequence of the pixel driving circuit also includes a threshold voltage acquisition and storage stage and a light-emitting stage. In the threshold voltage acquisition and storage stage of the first driving time sequence, the first storage capacitor Cst1 is configured to store the threshold voltage of the driving transistor T0. Also, in the light-emitting stage of the first driving time sequence, the first storage capacitor Cst1 is configured to maintain a voltage difference between the first node A and the third node S, so that the driving transistor T0 keeps in the on-state, so that the light-emitting element 11 emits light. In the threshold voltage acquisition and storage stage of the second driving time sequence, the second storage capacitor Cst2 is configured to store the threshold voltage of the driving transistor T0. Also, in the light-emitting stage of the second driving time sequence, the second storage capacitor Cst2 is configured to maintain a voltage difference between the second node B and the third node S, so that the driving transistor T0 keeps in the on-state, so that the light-emitting element 11 emits light.
As shown in
The driving time sequence of the pixel driving circuit also includes an initialization stage. In the initialization stage, a third scan signal output by the third scan signal terminal RD is at the high potential. The third transistor T3 is turned on by the third scan signal. A voltage of the third node S is the same as a voltage of the sensing signal terminal Vneg.
As shown in
In the threshold voltage acquisition and storage stage, the third scan signal output by the third scan signal terminal RD is at the low potential. The third transistor T3 is turned off under the control of the third scan signal, and the driving transistor T0 is turned off. The fourth scan signal output by the fourth scan signal terminal EM is at the high potential. The fourth transistor T4 is turned on by the fourth scan signal. The third node S is charged until its voltage is equal to a voltage difference between the first node or the second node and the threshold voltage of the driving transistor T0, thereby realizing the acquisition and storage of the threshold voltage of the driving transistor T0.
In some embodiments of the present disclosure, the first transistor T1, the second transistor T2, the third transistor T3, and the fourth transistor T4 are all N-type low-temperature polysilicon thin film transistors.
According to the pixel driving circuit provided in the above embodiments of the present disclosure, embodiments of the present disclosure also provide a driving method of the pixel driving circuit. The driving method is adapted to be configured as the pixel driving circuit provided in any of the above embodiments. As shown in
In any one frame period, one of the first gate G1 and the second gate G2 is controlled by the data signal to turn on the driving transistor T0. In a plurality of frame periods, the first gate G1 and the second gate G2 are alternately controlled by the data signal to turn on the driving transistor T0.
In the embodiment of the present disclosure, the driving time sequence of the driving method includes the first driving time sequence and the second driving time sequence. In the data writing stage t3 of the first driving time sequence, the writing module 10 connects the data signal terminal Data and the first node A. The data signal terminal Data outputs the data signal to the first node A. The data signal is at the high potential. The first gate G1 is controlled by the data signal to turn on the driving transistor T0. The writing module 10 disconnects the data signal terminal Data from the second node B. In the data clearing stage t4 of the first driving time sequence, the writing module 10 connects the data signal terminal Data and the second node B. The data signal terminal Data outputs the data signal to the second node B. The data signal is at the low potential. The second gate G2 is controlled by the data signal to turn off the driving transistor T0. The writing module 10 disconnects the data signal terminal Data from the first node A. In the data writing stage t3 of the second driving time sequence, the writing module 10 connects the data signal terminal Data and the second node B. The data signal terminal Data outputs the data signal to the second node B. The data signal is at the high potential. The second gate G2 is controlled by the data signal to turn on the driving transistor T0. The writing module 10 disconnects the data signal terminal Data from the first node A. In the data clearing stage t4 of the second driving time sequence, the writing module 10 connects the data signal terminal Data and the first node A. The data signal terminal Data outputs the data signal to the first node A. The data signal is at the low potential. The first gate G1 is controlled by the data signal to turn off the driving transistor T0. The writing module 10 disconnects the data signal terminal Data from the second node B.
In some embodiments of the present disclosure, in any one frame period, one of the first driving time sequence and the second driving time sequence is used to drive the pixel driving circuit. In a plurality of frame periods, the first driving time sequence and the second driving time sequence are alternately used to drive the pixel driving circuit. This can prevent the threshold voltage from drifting significantly due to long-term voltage application, thereby solving the problem of poor display caused by the drifting of the threshold voltage.
In some embodiments of the present disclosure, the first driving time sequence and the second driving time sequence are alternated every 100 frames. For example, in frames 1 to 100, the pixel driving circuit is driven in the first driving time sequence. In frames 101 to 200, the pixel circuit is driven in the second driving time sequence. In frames 201 to 300, the pixel driving circuit is driven in the first driving time sequence. In frames 301 to 400, the pixel driving circuit is driven in the second driving time sequence. The following analogy will not be repeated. In practical applications, the first driving time sequence and the second driving time sequence can be alternated every 1 frame, 10 frames, 20 frames, or more than 20 frames, which is not limited here.
Taking the first driving time sequence as an example, refer to
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It should be noted that the above embodiment only takes the first driving time sequence as an example. The second driving time sequence can refer to the first driving time sequence to drive the pixel driving circuit, which will not be described again here.
The pixel driving circuit provided in the above embodiments is provided according to the present disclosure. An embodiment of the present disclosure also provides a display panel. The display device includes the pixel driving circuit provided in any of the above embodiments. The display panel can be applied to, but is not limited to, display devices such as smartphones, smart watches, desktop computers, laptops, and televisions.
Advantages of the embodiments of the present disclosure are as follows. The embodiments of the present disclosure provide the pixel driving circuit, the driving method for the pixel driving circuit, and the display panel. The pixel driving circuit includes the writing module, the driving transistor, and the light-emitting element. The writing module is electrically connected to the data signal terminal, and is electrically connected to the first node and the second node. The writing module is configured to transmit the data signal output by the data signal terminal to the first node and the second node. The driving transistor is the double-gate transistor. The first gate of the driving transistor is electrically connected to the first node. The second gate of the driving transistor is electrically connected to the second node. The source of the driving transistor is electrically connected to the first power signal terminal. The drain of the driving transistor is electrically connected to the third node. The driving transistor is configured to transmit the first power signal output from the first power signal terminal to the third node. The light-emitting element is electrically connected to the second power signal terminal and electrically connected to the third node. In any one frame period, one of the first gate and the second gate is controlled by the data signal to turn on the driving transistor. Moreover, in the plurality of frame periods, the first gate and the second gate are alternately controlled by the data signal to turn on the driving transistor. It can prevent long-term voltage application to the same gate from causing some negative electrons in a channel layer to be captured into an interface between the channel layer and a gate insulating layer or directly into the gate insulating layer under the action of a gate voltage. Therefore, it can prevent the threshold voltage from drifting significantly due to long-term voltage application, thereby solving the problem of poor display caused by the drifting of the threshold voltage.
In summary, although the present disclosure is disclosed as above in preferred embodiments, the above preferred embodiments are not intended to limit the present disclosure. Those of ordinary skill in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure is based on the scope defined by the claims.
Number | Date | Country | Kind |
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202311227414.3 | Sep 2023 | CN | national |