CN114299860A - Pixel driving circuit and driving method thereof, display panel and display device - Google Patents
Pixel driving circuit and driving method thereof, display panel and display device Download PDFInfo
- Publication number
- CN114299860A CN114299860A CN202111658505.3A CN202111658505A CN114299860A CN 114299860 A CN114299860 A CN 114299860A CN 202111658505 A CN202111658505 A CN 202111658505A CN 114299860 A CN114299860 A CN 114299860A
- Authority
- CN
- China
- Prior art keywords
- light
- transistor
- driving
- pulse width
- emitting element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 28
- 230000004044 response Effects 0.000 claims description 12
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 claims description 11
- 230000000694 effects Effects 0.000 abstract description 10
- 230000008859 change Effects 0.000 abstract description 7
- 230000008569 process Effects 0.000 abstract description 7
- 230000005540 biological transmission Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 18
- 238000003079 width control Methods 0.000 description 9
- 239000003990 capacitor Substances 0.000 description 8
- 235000009508 confectionery Nutrition 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000002096 quantum dot Substances 0.000 description 2
- 238000000605 extraction Methods 0.000 description 1
- 238000004020 luminiscence type Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
Images
Landscapes
- Control Of El Displays (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
- Electroluminescent Light Sources (AREA)
Abstract
The invention provides a pixel driving circuit and a driving method thereof, a display panel and a display device.A working state of a light-emitting control unit comprises a plurality of first working states and second working states which are operated alternately in the display process of a frame of picture and in the stage that the light-emitting control unit controls the transmission of driving current to a light-emitting element; the driving current is transmitted to the light-emitting element in the first working state, and the driving current is stopped being transmitted to the light-emitting element in the second working state, so that the current density change of the driving current is small, the stability of the driving current output by the pixel driving circuit is high, the light-emitting efficiency and the chromaticity stability of the light-emitting element are high, and the display effect of the display device is improved.
Description
Technical Field
The present invention relates to the field of display technologies, and in particular, to a pixel driving circuit, a driving method thereof, a display panel, and a display device.
Background
With the increasing demand for display devices, the self-luminous display devices have been widely used in various electronic devices, including computers and mobile phones, due to their advantages of self-luminous, light and thin, low power consumption, high contrast, high color gamut, and flexible display. The self-luminous elements in the existing self-luminous display devices are generally Organic Light Emitting Diodes (OLEDs), Quantum Dot Light Emitting Diodes (QLEDs), Micro Light Emitting Diodes (Micro LEDs), and the like; in actual display, a pixel driving circuit generally outputs a driving current to drive a light emitting element to emit light, so that the display device achieves the purpose of displaying a picture. However, the current driving current output by the conventional pixel driving circuit varies greatly, which affects the light-emitting efficiency and chromaticity of the light-emitting element, and thus the display device has a poor display effect.
Disclosure of Invention
In view of this, the present invention provides a pixel driving circuit, a driving method thereof, a display panel and a display device, which effectively solve the technical problems in the prior art, ensure high stability of the driving current output by the pixel driving circuit, ensure high light-emitting efficiency and chromaticity stability of the light-emitting element, and improve the display effect of the display device.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a pixel driving circuit comprising: a pulse width modulation unit, an amplitude modulation unit, a light emission control unit, a driving transistor, and a light emitting element;
the pulse width modulation unit is used for outputting a pulse width setting signal to the grid electrode of the driving transistor;
the amplitude modulation unit is used for outputting an amplitude setting signal to the grid electrode of the driving transistor;
the driving transistor is used for outputting a driving current by referring to the pulse width setting signal and the amplitude setting signal;
the light emitting control unit is used for transmitting the driving current to the light emitting element, wherein the light emitting control unit comprises a plurality of first working states and second working states which are operated alternately, and the light emitting control unit transmits the driving current to the light emitting element in the first working state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state;
the light emitting element is configured to emit light in response to the driving current.
Optionally, the light-emitting control unit is configured to respond to a light-emitting control signal and transmit the driving current to the light-emitting element; the light-emitting control signal comprises a rectangular wave band, a first level of the rectangular wave band controls the light-emitting control unit to be in the first working state, and a second level of the rectangular wave band controls the light-emitting control unit to be in the second working state.
Optionally, the sum of the durations of all the first operating states is greater than or equal to the sum of the durations of all the second operating states.
Optionally, the durations of all the first operating states are the same;
and/or the duration of all of said second operating states is the same.
Optionally, the duration of the first operating state is greater than or equal to the duration of the second operating state.
Optionally, the durations of all the first operating states are the same, and the duration of the second operating state is in an increasing trend along with the change of time.
Correspondingly, the invention also provides a driving method of the pixel driving circuit, which is used for driving the pixel driving circuit, wherein the driving method comprises a signal generation stage and a light emitting control stage which are sequentially carried out;
in the signal generation phase, the pulse width modulation unit generates the pulse width setting signal, and the amplitude modulation unit transmits the amplitude setting signal to the grid of the driving transistor;
in the stage of controlling light emission, the pulse width modulation unit outputs the pulse width setting signal to the gate of the driving transistor, so that the driving transistor outputs a driving current with reference to the pulse width setting signal and the amplitude setting signal; at the same time, the light emission control unit transmits the driving current to the light emitting element for emitting light in response to the driving current; wherein the light emission control unit includes a plurality of first and second operation states alternately operated, and transmits the driving current to the light emitting element in the first operation state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state.
Optionally, a delay stage located between the signal generation stage and the light emission control stage is further included;
in the delay stage, the pulse width modulation unit outputs the pulse width setting signal to the gate of the driving transistor for a preset time before entering the light emitting control stage.
Correspondingly, the invention also provides a display panel which comprises the pixel driving circuit.
Correspondingly, the invention further provides a display device which comprises the display panel.
Compared with the prior art, the technical scheme provided by the invention at least has the following advantages:
the invention provides a pixel driving circuit, a driving method thereof, a display panel and a display device, comprising: a pulse width modulation unit, an amplitude modulation unit, a light emission control unit, a driving transistor, and a light emitting element; the pulse width modulation unit is used for outputting a pulse width setting signal to the grid electrode of the driving transistor; the amplitude modulation unit is used for outputting an amplitude setting signal to the grid electrode of the driving transistor; the driving transistor is used for outputting a driving current by referring to the pulse width setting signal and the amplitude setting signal; the light emitting control unit is used for transmitting the driving current to the light emitting element, wherein the light emitting control unit comprises a plurality of first working states and second working states which are operated alternately, and the light emitting control unit transmits the driving current to the light emitting element in the first working state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state; the light emitting element is configured to emit light in response to the driving current.
As can be seen from the above, in the technical solution provided by the present invention, in the process of displaying a frame of image and in the phase of controlling the driving current to be transmitted to the light emitting element by the light emitting control unit, the working state of the light emitting control unit includes a plurality of first working states and second working states which are operated alternately; the driving current is transmitted to the light-emitting element in the first working state, and the driving current is stopped being transmitted to the light-emitting element in the second working state, so that the current density change of the driving current is small, the stability of the driving current output by the pixel driving circuit is high, the light-emitting efficiency and the chromaticity stability of the light-emitting element are high, and the display effect of the display device is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a pixel driving circuit according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of another pixel driving circuit according to an embodiment of the present invention;
FIG. 3 is a timing diagram according to an embodiment of the present invention;
FIG. 4 is another timing diagram provided by an embodiment of the present invention;
FIG. 5 is a timing diagram of another embodiment of the present invention;
FIG. 6 is a timing diagram of another embodiment of the present invention;
fig. 7 is a schematic structural diagram of another pixel driving circuit according to an embodiment of the invention;
fig. 8 is a flowchart illustrating a driving method of a pixel driving circuit according to an embodiment of the invention;
fig. 9 is a flowchart of another driving method of a pixel driving circuit according to an embodiment of the invention;
FIG. 10 is a timing diagram of another embodiment of the present invention;
fig. 11 is a schematic structural diagram of a display panel according to an embodiment of the present invention;
fig. 12 is a schematic structural diagram of a display device according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As background art shows, the demand for display devices has been increasing with the increase of display technology, and among various display technologies, self-luminous display devices have been widely used in various electronic devices including electronic products such as computers and mobile phones due to their advantages of self-luminescence, lightness, thinness, low power consumption, high contrast, high color gamut, and flexible display. The self-luminous elements in the existing self-luminous display devices are generally Organic Light Emitting Diodes (OLEDs), Quantum Dot Light Emitting Diodes (QLEDs), Micro Light Emitting Diodes (Micro LEDs), and the like; in actual display, a pixel driving circuit generally outputs a driving current to drive a light emitting element to emit light, so that the display device achieves the purpose of displaying a picture. However, the current driving current output by the conventional pixel driving circuit varies greatly, which affects the light-emitting efficiency and chromaticity of the light-emitting element, and thus the display device has a poor display effect.
Accordingly, embodiments of the present invention provide a pixel driving circuit, a driving method thereof, a display panel, and a display device, which effectively solve the technical problems in the prior art, ensure high stability of a driving current output by the pixel driving circuit, ensure high light-emitting efficiency and chromaticity stability of a light-emitting element, and improve a display effect of the display device.
To achieve the above object, the technical solutions provided by the embodiments of the present invention are described in detail below, specifically with reference to fig. 1 to 12.
Referring to fig. 1, a schematic structural diagram of a pixel driving circuit according to an embodiment of the present invention is shown, where the pixel driving circuit includes: a pulse width modulation unit 100, an amplitude modulation unit 200, a light emission control unit 300, a driving transistor T0, and a light emitting element 400.
The pulse width modulation unit 100 is configured to output a pulse width setting signal to the gate of the driving transistor T0.
The amplitude modulation unit 200 is configured to output an amplitude setting signal to the gate of the driving transistor T0.
The driving transistor T0 is used for outputting a driving current with reference to the pulse width setting signal and the amplitude setting signal.
The light emitting control unit 300 is configured to transmit the driving current to the light emitting element 400, wherein the light emitting control unit 300 includes a plurality of first and second operating states alternately operating, and the light emitting control unit 300 transmits the driving current to the light emitting element 400 in the first operating state; and the light emitting control unit 300 stops transmitting the driving current to the light emitting element 400 in the second operation state.
The light emitting element 400 is used for emitting light in response to the driving current, wherein the light emitting element 400 may be a light emitting diode. The light emitting diode provided by the embodiment of the invention can be a micro light emitting diode, such as a mini-LED, a micro-LED and the like. It is understood that the light emitting element emits light in response to a driving current, and a current density variation of the driving current directly affects light extraction efficiency and chromaticity of the light emitting element. The light-emitting control unit of the prior art works by continuously transmitting the driving current to the light-emitting element until the driving transistor stops generating the driving current. In the process of continuously flowing current into the light emitting element, the change of the current density is in a continuous descending trend, so that the light emitting efficiency and the chromaticity of the light emitting element from the initial lighting time to the extinguishing time are continuously changed in the process, and the image display effect of the conventional display device is poor.
According to the technical scheme provided by the embodiment of the invention, in the process of displaying a frame of picture and in the stage of controlling the driving current to be transmitted to the light-emitting element by the light-emitting control unit, the working state of the light-emitting control unit comprises a plurality of first working states and second working states which are operated alternately; the driving current is transmitted to the light-emitting element in the first working state, and the driving current is stopped being transmitted to the light-emitting element in the second working state, so that the current density change of the driving current in the display process of a frame of picture is small, the stability of the driving current output by the pixel driving circuit is high, the light-emitting efficiency and the chromaticity stability of the light-emitting element are high, and the display effect of the display device is improved.
In an embodiment of the present invention, the first operating state and the second operating state of the light emitting control unit provided in the present invention, which operate alternately, may be controlled by the light emitting control signal connected thereto, or implemented by a special circuit structure of the light emitting control unit, and the present invention is not limited specifically. Specifically, the light-emitting control unit provided by the invention is used for responding to a light-emitting control signal and transmitting the driving current to the light-emitting element; the light-emitting control signal comprises a rectangular wave band, a first level of the rectangular wave band controls the light-emitting control unit to be in the first working state, and a second level of the rectangular wave band controls the light-emitting control unit to be in the second working state.
It can be understood that, in the light-emitting control unit provided in the embodiment of the present invention, if the low level can control the light-emitting control unit to operate, and the high level can control the light-emitting unit to stop operating, the first level is the low level, and the second level is the high level. On the contrary, if the high level can control the light emitting control unit to operate, and the low level can control the light emitting unit to stop operating, the first level is the high level, and the second level is the low level, which needs to be specifically analyzed according to whether the transistor included in the light emitting control unit is of the N-type or the P-type.
The technical solution provided by the embodiments of the present invention is described in more detail below with reference to the drawings of specific component structures of pixel driving circuits. It should be noted that the specific pixel driving circuit structure provided in the following embodiments of the present invention is only one of all applicable circuit structures of the present invention, and other structures may also be provided in other embodiments of the present invention. In the following embodiments of the present invention, the transistors of the pixel driving circuit are P-type transistors. In other embodiments of the present invention, the transistors of the pixel driving circuit may be all N-type transistors, or a part of the transistors may be P-type transistors and a part of the transistors may be N-type transistors.
Referring to fig. 2, a schematic structural diagram of another pixel driving circuit according to an embodiment of the present invention is shown, wherein the pulse width modulation unit 100 according to the embodiment of the present invention includes a first transistor T1, a second transistor T2, a third transistor T3, a fourth transistor T4, a fifth transistor T5, a sixth transistor T6, and a first capacitor C1.
The first terminal of the first transistor T1 is connected to the reset voltage Vref, the second terminal of the first transistor T1 is electrically connected to the gate of the second transistor T2, the second terminal of the fourth transistor T4 and the second terminal of the first capacitor C1, the gate of the first transistor T1 is connected to the first control signal S1, and the first terminal of the first capacitor C1 is connected to the pulse width control voltage sweet, where the pulse width control voltage sweet is a linearly decreasing voltage.
The first end of the second transistor T2 is electrically connected to the second end of the third transistor T3 and the second end of the fifth transistor T5, the second end of the second transistor T2 is electrically connected to the first end of the fourth transistor T4 and the first end of the sixth transistor T6, the first end of the third transistor T3 is connected to the first data voltage D1, the gate of the third transistor T3 is connected to the second control signal S2, the first end of the fifth transistor T5 is connected to the off-voltage Voff, the gate of the fifth transistor T5 is connected to the pulse width control signal K2, the second end of the sixth transistor T6 is electrically connected to the gate of the driving transistor T0, and the gate of the sixth transistor T6 is connected to the pulse width control signal K2.
As shown in fig. 2, the amplitude modulation unit 200 according to the embodiment of the present invention includes a seventh transistor T7, an eighth transistor T8, a ninth transistor T9, and a second capacitor C2.
A first end of the seventh transistor T7 is connected to the reset voltage Vref, a second end of the seventh transistor T7 is electrically connected to the gate of the driving transistor T0, a second end of the eighth transistor T8 and a second end of the second capacitor C2, a gate of the seventh transistor T7 is connected to the first control signal S1, a first end of the eighth transistor T8 is electrically connected to the second end of the driving transistor T0, a gate of the eighth transistor T8 is connected to the second control signal S2, and a first end of the second capacitor C2 is connected to the first power voltage V1.
And a first terminal of the ninth transistor T9 is connected to the second data voltage D2, a second terminal of the ninth transistor T9 is electrically connected to the first terminal of the driving transistor T0, and a gate of the ninth transistor T9 is connected to the second control signal S2.
As shown in fig. 2, the light emission control unit 300 according to the embodiment of the present invention includes a tenth transistor T10 and an eleventh transistor T11.
A first terminal of the tenth transistor T10 is connected to the first power voltage V1, a second terminal of the tenth transistor T10 is electrically connected to the first terminal of the driving transistor T0, and a gate of the tenth transistor T10 is connected to the light emission control signal K1.
And a first terminal of the eleventh transistor T11 is electrically connected to the second terminal of the driving transistor T0, a second terminal of the eleventh transistor T11 is electrically connected to the first terminal of the light emitting device 400, a gate of the eleventh transistor T11 is connected to the light emission control signal K1, and a second terminal of the light emitting device 400 is connected to the second power voltage V2, wherein the first power voltage V1 is greater than the second power voltage V2.
In an embodiment of the invention, at least one of the transistors included in the pixel driving circuit provided by the invention can be a double-gate transistor, so as to improve the response speed of the transistor and reduce the leakage current of the transistor. The first transistor T1, the fourth transistor T4, the seventh transistor T7 and the eighth transistor T8 provided in the embodiments of the present invention may be double-gate transistors, so as to improve the response speed of these transistors and reduce the leakage current of these transistors, and finally improve the stability of the pixel driving circuit.
Further referring to fig. 3, a timing diagram according to an embodiment of the invention is provided. The driving method of the pixel driving circuit provided by the embodiment of the invention comprises a signal generation stage S11 and a light-emitting control stage S12 which are sequentially carried out.
Wherein, the signal generation stage S11 includes a first sub-signal generation stage S111 and a second sub-signal generation stage S112 performed in sequence; in the signal generation stage S11, the light emission control signal K1 and the pulse width control signal K2 are at high level, and the connected transistors are controlled to be turned off. During the first sub-signal generating stage S111, the first control signal S1 is at a low level, and the second control signal S2 is at a high level; at this time, the first control signal S1 controls the first transistor T1 and the seventh transistor T7 to be turned on, and thus, the reset voltage Vref is transmitted to the gate of the second transistor T2 and the gate of the driving transistor T0 to reset the second transistor T2 and the driving transistor T0; and the transistor with its gate tied to the second control signal S2 is off at this time.
Then, in the second sub-signal generating stage S112, the first control signal S1 is at a high level, and the second control signal S2 is at a low level; at this time, the second control signal S2 controls the third transistor T3, the fourth transistor T4, the eighth transistor T8 and the ninth transistor T9 to be turned on, and the first data voltage D1 is transmitted to the gate of the second transistor T2 through the third transistor T3, the second transistor T2 and the fourth transistor T4, so that the writing of the first data voltage D1, that is, the generation of the pulse width setting signal is completed; and the second data voltage D2 is transmitted to the gate of the driving transistor T0 through the ninth transistor T9, the driving transistor T0 and the eighth transistor T8, completing the writing of the second data voltage D2, i.e., completing the transmission of the amplitude setting signal to the gate of the driving transistor T0.
And, the control lighting phase S12 includes a lighting sub-phase S121 and a turn-off sub-phase S122, which are performed in sequence; in the control light-emitting period S12, the first control signal S1 and the second control signal S2 are high, and the connected transistors are turned off. In the light-emitting sub-phase S121, the light-emitting control signal K1 and the pulse width control signal K2 are both at a low level, and the fifth transistor T5, the sixth transistor T6, the tenth transistor T10 and the eleventh transistor T11 are controlled to be turned on; at this time, the pulse width modulation voltage sweet controls the second transistor T2 to keep off through the first capacitor C1, although the fifth transistor T5 is turned on, the off-voltage Voff cannot be transmitted to the gate of the driving transistor T0 through the second transistor T2, and the pulse width setting signal transmitted by the sixth transistor T6 is substantially a floating signal; the tenth transistor T0 and the eleventh transistor T11 are turned on to turn on a path from the first power voltage V1 to the second power voltage V2, and the driving current generated by the driving transistor T0 is transmitted to the light emitting element 400; at this time, the light emission control signal K1 is a rectangular wave band, and when the rectangular wave band is at a low level, the rectangular wave band is in the first operation state to transmit the driving current to the light emitting element 400, and when the rectangular wave band is at a high level, the rectangular wave band is in the second operation state to stop transmitting the driving current to the light emitting element 400.
Then, in the turn-off sub-stage S122, the light-emitting control signal K1 and the pulse width control signal K2 are at low level, and the corresponding transistors are controlled to be turned on; and, the pwm voltage sweet is a linear decreasing voltage, at this stage, the second transistor T2 cannot be maintained to be turned off through the first capacitor C1 and is controlled to be in an on state, the off voltage Voff is transmitted to the gate of the driving transistor T0 through the fifth transistor T5, the second transistor T2 and the sixth transistor T6 to control the driving transistor T0 to be turned off, and at this time, the driving transistor T0 no longer generates a driving current, so that the light emitting device 400 is kept turned off.
Referring to fig. 4, another timing diagram provided by the embodiment of the present invention is shown, wherein the sum of the durations a1 of all the first operating states provided by the present invention is greater than or equal to the sum of the durations a2 of all the second operating states. The invention sets the sum of the duration a1 of all the first working states to be more than or equal to the sum of the duration a2 of all the second working states, thereby ensuring the inflow duration of the driving current and ensuring the high luminous efficiency of the luminous element.
Referring to fig. 5, a timing diagram for an embodiment of the present invention is provided, in which all the first operating states provided by the embodiment of the present invention have the same duration a 1; and/or the duration a2 of all the second operating states is the same, so as to facilitate the debugging of the rectangular wave band. Optionally, the duration a1 of the first operating state provided by the embodiment of the present invention is greater than or equal to the duration a2 of the second operating state.
Referring to fig. 6, a timing chart provided by the embodiment of the present invention is further shown, wherein the duration a1 of all the first operating states provided by the embodiment of the present invention is the same, and the duration a2 of the second operating state is in an increasing trend with time. Since the driving current tends to decrease with time, the duration a2 of the second operating state is set to be gradually longer, so that the degree of reduction of the driving current is lower, the current density change of the driving current is smaller, and the display effect of the display device is high.
With reference to fig. 7, a schematic structural diagram of another pixel driving circuit according to an embodiment of the present invention is further provided, wherein the pixel driving circuit further includes a twelfth transistor T12, a first end of the twelfth transistor T12 is connected to the reset voltage Vref, a second end of the twelfth transistor T12 is electrically connected to the first end of the light emitting element 400, and a gate of the twelfth transistor T12 is connected to the third control signal S3. The twelfth transistor T12 responds to the control of the second control signal S3 and transmits the reset voltage Vref to the first terminal of the light emitting device 400 to reset the light emitting device 400, thereby improving the stability of the pixel driving circuit. Optionally, the third control signal S3 and the first control signal S1 provided in the embodiment of the present invention are the same signal, or the third control signal S3 and the second control signal S2 are the same signal, which is not limited in the present invention.
Accordingly, an embodiment of the present invention provides a driving method for a pixel driving circuit, which is used for driving the pixel driving circuit provided in any one of the embodiments. Referring to fig. 8, a flowchart of a driving method of a pixel driving circuit according to an embodiment of the present invention is shown, wherein the driving method includes a signal generation phase S11 and a light emission control phase S12 which are performed sequentially.
S11, in the signal generating stage, the pulse width modulating unit generates the pulse width setting signal, and the amplitude modulating unit transmits the amplitude setting signal to the gate of the driving transistor.
S12, in the light emitting control phase, the pulse width modulation unit outputs the pulse width setting signal to the gate of the driving transistor, so that the driving transistor outputs a driving current with reference to the pulse width setting signal and the amplitude setting signal; at the same time, the light emission control unit transmits the driving current to the light emitting element for emitting light in response to the driving current; wherein the light emission control unit includes a plurality of first and second operation states alternately operated, and transmits the driving current to the light emitting element in the first operation state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state.
Referring to fig. 9, a flowchart of a driving method of another pixel driving circuit according to an embodiment of the present invention is provided, in which the driving method further includes a delay stage S13 between the signal generation stage S11 and the light emission control stage S12.
S13, in the delay stage, the pwm unit outputs the pulse width setting signal to the gate of the driving transistor for a preset time, and then enters the light emitting control stage S12.
It can be understood that, the pulse width modulation unit provided in the embodiment of the present invention firstly transmits the pulse width setting signal to the gate of the driving transistor for the preset time, and then controls the light emitting unit to transmit the driving current to the light emitting element, so as to prevent the initial time of generating the driving current by the driving transistor from being in the fluctuation stage of the pulse width setting signal, and improve the stability of the pixel driving circuit. As shown in fig. 10 and fig. 2, in the delay stage S13, the pulse width control signal K2 is at a low level, and the light emission control signal K1 is at a high level; the pulse width control signal K2 enters the light emission control stage S12 after controlling the sixth transistor T6 to transmit the pulse width setting signal to the gate of the driving transistor T0 for a certain time, so as to prevent the initial time of the driving transistor T0 generating the driving current from being in the fluctuation stage of the pulse width setting signal, thereby improving the stability of the pixel driving circuit.
Correspondingly, the embodiment of the invention also provides a display panel, and the display panel comprises the pixel driving circuit provided by any one of the embodiments.
Referring to fig. 11, a schematic structural diagram of a display panel according to an embodiment of the present invention is shown, where the display panel includes a display area AA and a non-display area NA located at a periphery of the display area AA, where the display area AA includes a plurality of sub-pixels 500, and each sub-pixel 500 includes a pixel driving circuit, where the pixel driving circuit is the pixel driving circuit provided in any one of the embodiments.
Correspondingly, the embodiment of the invention also provides a display device, and the display device comprises the display panel provided by any one of the embodiments.
Referring to fig. 12, a schematic structural diagram of a display device according to an embodiment of the present invention is shown, where the display device 1000 according to the embodiment of the present invention may be a mobile terminal, and the mobile terminal includes the display panel according to any one of the embodiments.
It should be noted that the display device provided in the embodiment of the present invention may also be a notebook, a tablet, a computer, a wearable device, and the like, and the present invention is not limited in particular.
The embodiment of the invention provides a pixel driving circuit, a driving method thereof, a display panel and a display device, wherein the pixel driving circuit comprises: a pulse width modulation unit, an amplitude modulation unit, a light emission control unit, a driving transistor, and a light emitting element; the pulse width modulation unit is used for outputting a pulse width setting signal to the grid electrode of the driving transistor; the amplitude modulation unit is used for outputting an amplitude setting signal to the grid electrode of the driving transistor; the driving transistor is used for outputting a driving current by referring to the pulse width setting signal and the amplitude setting signal; the light emitting control unit is used for transmitting the driving current to the light emitting element, wherein the light emitting control unit comprises a plurality of first working states and second working states which are operated alternately, and the light emitting control unit transmits the driving current to the light emitting element in the first working state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state; the light emitting element is configured to emit light in response to the driving current.
As can be seen from the above, in the technical solution provided in the embodiment of the present invention, in the process of displaying a frame of image and in the phase when the light-emitting control unit controls the transmission of the driving current to the light-emitting element, the working state of the light-emitting control unit includes a plurality of first working states and second working states which are operated alternately; the driving current is transmitted to the light-emitting element in the first working state, and the driving current is stopped being transmitted to the light-emitting element in the second working state, so that the current density change of the driving current is small, the stability of the driving current output by the pixel driving circuit is high, the light-emitting efficiency and the chromaticity stability of the light-emitting element are high, and the display effect of the display device is improved.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A pixel driving circuit, comprising: a pulse width modulation unit, an amplitude modulation unit, a light emission control unit, a driving transistor, and a light emitting element;
the pulse width modulation unit is used for outputting a pulse width setting signal to the grid electrode of the driving transistor;
the amplitude modulation unit is used for outputting an amplitude setting signal to the grid electrode of the driving transistor;
the driving transistor is used for outputting a driving current by referring to the pulse width setting signal and the amplitude setting signal;
the light emitting control unit is used for transmitting the driving current to the light emitting element, wherein the light emitting control unit comprises a plurality of first working states and second working states which are operated alternately, and the light emitting control unit transmits the driving current to the light emitting element in the first working state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state;
the light emitting element is configured to emit light in response to the driving current.
2. The pixel driving circuit according to claim 1, wherein the light emission control unit is configured to transmit the driving current to the light emitting element in response to a light emission control signal; the light-emitting control signal comprises a rectangular wave band, a first level of the rectangular wave band controls the light-emitting control unit to be in the first working state, and a second level of the rectangular wave band controls the light-emitting control unit to be in the second working state.
3. The pixel driving circuit according to claim 1, wherein the sum of the durations of all of the first operating states is greater than or equal to the sum of the durations of all of the second operating states.
4. A pixel driving circuit according to claim 3, wherein the duration of all of the first operating states is the same;
and/or the duration of all of said second operating states is the same.
5. The pixel driving circuit according to claim 4, wherein the duration of the first operating state is greater than or equal to the duration of the second operating state.
6. The pixel driving circuit according to claim 3, wherein the duration of all of the first operating states is the same, and the duration of the second operating states increases with time.
7. A driving method of a pixel driving circuit for driving the pixel driving circuit according to any one of claims 1 to 6, wherein the driving method comprises a signal generation phase and a light emission control phase which are performed in sequence;
in the signal generation phase, the pulse width modulation unit generates the pulse width setting signal, and the amplitude modulation unit transmits the amplitude setting signal to the grid of the driving transistor;
in the stage of controlling light emission, the pulse width modulation unit outputs the pulse width setting signal to the gate of the driving transistor, so that the driving transistor outputs a driving current with reference to the pulse width setting signal and the amplitude setting signal; at the same time, the light emission control unit transmits the driving current to the light emitting element for emitting light in response to the driving current; wherein the light emission control unit includes a plurality of first and second operation states alternately operated, and transmits the driving current to the light emitting element in the first operation state; and the light-emitting control unit stops transmitting the driving current to the light-emitting element in the second working state.
8. The driving method of the pixel driving circuit according to claim 7, further comprising a delay stage between the signal generation stage and the light emission control stage;
in the delay stage, the pulse width modulation unit outputs the pulse width setting signal to the gate of the driving transistor for a preset time before entering the light emitting control stage.
9. A display panel comprising the pixel driving circuit according to any one of claims 1 to 8.
10. A display device characterized by comprising the display panel according to claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111658505.3A CN114299860A (en) | 2021-12-30 | 2021-12-30 | Pixel driving circuit and driving method thereof, display panel and display device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111658505.3A CN114299860A (en) | 2021-12-30 | 2021-12-30 | Pixel driving circuit and driving method thereof, display panel and display device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114299860A true CN114299860A (en) | 2022-04-08 |
Family
ID=80973033
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111658505.3A Pending CN114299860A (en) | 2021-12-30 | 2021-12-30 | Pixel driving circuit and driving method thereof, display panel and display device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114299860A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114299866A (en) * | 2021-12-31 | 2022-04-08 | 湖北长江新型显示产业创新中心有限公司 | Display panel and display device |
| WO2024032340A1 (en) * | 2022-08-08 | 2024-02-15 | 成都辰显光电有限公司 | Display panel, display panel driving method, and display device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110021264A (en) * | 2018-09-07 | 2019-07-16 | 京东方科技集团股份有限公司 | Pixel circuit and its driving method, display panel |
| CN111462685A (en) * | 2020-05-29 | 2020-07-28 | 上海天马有机发光显示技术有限公司 | Pixel driving circuit and driving method thereof, display panel and display device |
| CN112116890A (en) * | 2020-10-15 | 2020-12-22 | 厦门天马微电子有限公司 | Display panel, driving method thereof and display device |
| CN113396452A (en) * | 2019-03-29 | 2021-09-14 | 三星电子株式会社 | Display panel and driving method of display panel |
-
2021
- 2021-12-30 CN CN202111658505.3A patent/CN114299860A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110021264A (en) * | 2018-09-07 | 2019-07-16 | 京东方科技集团股份有限公司 | Pixel circuit and its driving method, display panel |
| CN113396452A (en) * | 2019-03-29 | 2021-09-14 | 三星电子株式会社 | Display panel and driving method of display panel |
| CN111462685A (en) * | 2020-05-29 | 2020-07-28 | 上海天马有机发光显示技术有限公司 | Pixel driving circuit and driving method thereof, display panel and display device |
| CN112116890A (en) * | 2020-10-15 | 2020-12-22 | 厦门天马微电子有限公司 | Display panel, driving method thereof and display device |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114299866A (en) * | 2021-12-31 | 2022-04-08 | 湖北长江新型显示产业创新中心有限公司 | Display panel and display device |
| WO2024032340A1 (en) * | 2022-08-08 | 2024-02-15 | 成都辰显光电有限公司 | Display panel, display panel driving method, and display device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111462685B (en) | Pixel driving circuit and driving method thereof, display panel and display device | |
| US10186187B2 (en) | Organic light-emitting diode display with pulse-width-modulated brightness control | |
| CN114758619A (en) | Pixel circuit, driving method thereof, display panel and display device | |
| CN110085164B (en) | Display panel and display device | |
| CN111276097B (en) | Pixel driving circuit, driving method thereof and display substrate | |
| CN108877645A (en) | Pixel circuit and its driving method, display panel, mosaic screen | |
| CN114299866A (en) | Display panel and display device | |
| KR20210027672A (en) | Pixel circuit | |
| US20220223109A1 (en) | Shift register circuit and its driving method, display panel, and display device | |
| CN114299860A (en) | Pixel driving circuit and driving method thereof, display panel and display device | |
| CN114495825A (en) | Pixel driving circuit, driving method, display panel and display device | |
| CN110400541B (en) | Display panel and display device | |
| US20210358419A1 (en) | Display driving method, display driving device and display module | |
| CN111599309A (en) | Pixel driving circuit, organic light-emitting display panel and display device | |
| US11308860B2 (en) | Pixel circuit and driving method, pixel unit, display panel | |
| CN110992885A (en) | Pixel driving circuit, driving method thereof and display panel | |
| WO2022247467A1 (en) | Display panel and display device | |
| WO2021077487A1 (en) | Pixel unit and display panel | |
| CN112967665B (en) | Light emitting element control circuit, display panel and display device | |
| CN204117567U (en) | A kind of image element circuit and display panel | |
| US20240135884A1 (en) | Display panel driving method and display panel | |
| CN215868588U (en) | Light-emitting drive circuit and display panel | |
| CN203085137U (en) | Pixel circuit, organic electroluminescence display panel and display device | |
| CN113948032B (en) | Pixel circuit and driving method thereof | |
| CN114299870A (en) | Drive circuit and display panel |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20220408 |