CN111179864B - Pixel driving circuit, driving method thereof, display device and electronic equipment - Google Patents
Pixel driving circuit, driving method thereof, display device and electronic equipment Download PDFInfo
- Publication number
- CN111179864B CN111179864B CN202010049484.4A CN202010049484A CN111179864B CN 111179864 B CN111179864 B CN 111179864B CN 202010049484 A CN202010049484 A CN 202010049484A CN 111179864 B CN111179864 B CN 111179864B
- Authority
- CN
- China
- Prior art keywords
- signal
- light
- unit
- driving
- transistor
- 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.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
Abstract
The invention relates to a pixel driving circuit and a driving method thereof, a display device and electronic equipment, wherein the pixel driving circuit comprises a driving unit, a first switch unit and an energy storage unit, the driving unit comprises a first end, a second end and a control end, the first end of the driving unit is connected with a first signal end, and the second end of the driving unit is connected with a light-emitting element; the first end of the first switch unit is connected with the second signal end, the second end of the first switch unit is connected with the control end of the driving unit, and the control end of the first switch unit is connected with the scanning signal end; the first end of the first energy storage unit is connected with the control end of the driving unit, and the second end of the first energy storage unit is connected with the reference power end; the first signal terminal is used for outputting an initialization signal in a reset stage and outputting a first power supply signal in a light-emitting stage, and the second signal terminal is used for outputting a reference signal in a reset stage and outputting a data signal in a data writing stage. The pixel driving circuit can increase the light transmittance of the under-screen camera.
Description
Technical Field
The disclosure relates to the technical field of electronic equipment, and in particular relates to a pixel driving circuit, a driving method thereof, a display device and electronic equipment.
Background
With the development and progress of technology, the requirements of the screen ratio of the electronic device are increasing. And the front camera of the electronic device seriously hinders the improvement of the screen ratio of the electronic device.
In order to further increase the screen ratio of electronic devices, an under-screen camera technology has been developed that increases the screen ratio by disposing a front-facing camera under a display device. At present, the technology of the under-screen camera has the problem that the light transmittance of the camera area is insufficient.
It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the present disclosure and thus may include information that does not constitute prior art known to those of ordinary skill in the art.
Disclosure of Invention
The disclosure aims to provide a pixel driving circuit, a driving method thereof, a display device and electronic equipment, and further solve the problem that the light transmittance of a camera area is insufficient in the under-screen camera technology to at least a certain extent.
According to a first aspect of the present disclosure, there is provided a pixel driving circuit including:
the driving unit comprises a first end, a second end and a control end, wherein the first end of the driving unit is connected with the first signal end, and the second end of the driving unit is connected with the light-emitting element;
the first end of the first switch unit is connected with the second signal end, the second end of the first switch unit is connected with the control end of the driving unit, and the control end of the first switch unit is connected with the scanning signal end;
the first end of the first energy storage unit is connected with the control end of the driving unit, and the second end of the first energy storage unit is connected with the reference power supply end;
the first signal end is used for outputting an initialization signal in a reset stage and outputting a first power supply signal in a light-emitting stage, the second signal end is used for outputting a reference signal in the reset stage and outputting a data signal in a data writing stage, the first switch unit is turned on in response to the scanning signal in the reset stage so as to transmit the reference signal to a control end of the driving unit, and the driving unit is turned on so as to transmit the initialization signal to the light-emitting element; the first switch unit is turned on in response to the scan signal during a data writing period to write the data signal into the first energy storage unit.
According to a second aspect of the present disclosure, there is provided a driving method of a pixel driving circuit for the above-described pixel driving circuit, the method comprising:
the first switch unit is turned on by the scanning signal, and a reference signal is transmitted to the control end of the driving unit so as to turn on the driving unit to transmit an initialization signal to the light-emitting element;
the first switch unit is turned on by the scanning signal, and the data signal is stored in the first energy storage unit;
and the data signals in the first energy storage unit are utilized to conduct the driving unit so that the first power supply signals are transmitted to the light emitting element, and the light emitting element is driven to emit light.
According to a third aspect of the present disclosure, there is provided a display device including:
a first display area;
the light transmittance of the first display area is larger than that of the second display area, and the pixel driving circuit is arranged on the first display area.
According to a fourth aspect of the present disclosure, there is provided an electronic apparatus including the display device described above.
According to the pixel driving circuit provided by the embodiment of the disclosure, the initialization signal is provided through the first signal end, the reference signal is provided through the second signal end, the reset of the light emitting element can be realized in the reset stage, the need of setting an independent reset unit in the pixel driving circuit to reset the pixel driving circuit is avoided, the number of wires and transistors in the driving circuit layer of the display device is further reduced, the light transmittance of the under-screen camera area is increased, and the imaging quality of the under-screen camera is improved.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Drawings
The above and other features and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.
Fig. 1 is a schematic diagram of a first pixel driving circuit provided in an exemplary embodiment of the present disclosure;
fig. 2 is a schematic diagram of a second pixel driving circuit provided in an exemplary embodiment of the present disclosure;
fig. 3 is a schematic diagram of a third pixel driving circuit provided in an exemplary embodiment of the present disclosure;
fig. 4 is a schematic diagram of a fourth pixel driving circuit provided in an exemplary embodiment of the present disclosure;
fig. 5 is a schematic diagram of a fifth pixel driving circuit provided in an exemplary embodiment of the present disclosure;
fig. 6 is a timing diagram of a pixel driving circuit provided in an exemplary embodiment of the present disclosure;
fig. 7 is a timing diagram of another pixel driving circuit provided by an exemplary embodiment of the present disclosure;
fig. 8 is a flowchart of a driving method of a pixel driving circuit according to an exemplary embodiment of the present disclosure;
fig. 9 is a schematic diagram of a display device according to an exemplary embodiment of the present disclosure;
fig. 10 is a schematic diagram of an electronic device according to an exemplary embodiment of the present disclosure.
In the figure: 110. a driving unit; 120. a first switching unit; 130. a first energy storage unit; 140. a first signal terminal; 150. a second signal terminal; 160. a light emitting unit; 170. a second energy storage unit; 180. a first light emission control unit; 190. a second light emission control unit; 210. a first display area; 211. a first pixel unit; 212. a first power line; 220. a second display area; 221. a second pixel unit; 222. a second power line; 300. a camera; 20. a frame; 30. a main board; 40. a battery; 50. a rear cover;
DT and a driving transistor; t1, a first transistor; t2, a second transistor; t3, third transistor; c1, a first energy storage capacitor; and C2, a second energy storage capacitor.
Detailed Description
Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted.
In order to realize some specific functions in a display device of an electronic apparatus, one or more designated display areas often need to be disposed in the display device, and the light transmittance of the designated display areas needs to be greater than that of other areas of the display device. For example, the area corresponding to the lower camera.
The exemplary embodiments of the present disclosure first provide a pixel driving circuit, as shown in fig. 1, including: a driving unit 110, a first switching unit 120, and a first energy storage unit 130; the driving unit 110 includes a first end, a second end and a control end, the first end of the driving unit 110 is connected to the first signal end 140, and the second end of the driving unit 110 is connected to the light emitting element 160. The first end of the first switch unit 120 is connected to the second signal end 150, the second end of the first switch unit 120 is connected to the control end of the driving unit 110, and the control end of the first switch unit 120 is connected to the scan signal Sn end. The first end of the first energy storage unit 130 is connected to the control end of the driving unit 110, and the second end of the first energy storage unit 130 is connected to the reference power end.
The first signal terminal 140 is configured to output an initialization signal Vint during a reset phase and output a first power signal VDD during a light-emitting phase, the second signal terminal 150 is configured to output a reference signal Vref during a reset phase and output a data signal Vdata during a data writing phase, the first switch unit 120 is turned on in response to the scan signal Sn during the reset phase to transmit the reference signal Vref to the control terminal of the driving unit 110, and the driving unit 110 is turned on to transmit the initialization signal Vint to the light-emitting element 160; in the data writing stage, the first switch unit 120 is turned on in response to the scan signal Sn to write the data signal Vdata into the first energy storage unit 130.
According to the pixel driving circuit provided by the embodiment of the disclosure, the initialization signal Vint is provided through the first signal end 140, the reference signal Vref is provided through the second signal end 150, the light-emitting element 160 can be reset in the resetting stage, the pixel driving circuit is prevented from being reset by an independent resetting unit, the number of wires and transistors in the driving circuit layer of the display device is reduced, the light transmittance of the under-screen camera area is increased, and the imaging quality of the under-screen camera is improved.
Further, as shown in fig. 2, the pixel driving circuit provided in the embodiment of the present disclosure may further include a second energy storage unit 170, a first light emission control unit 180, and a second light emission control unit 190. The first end of the second energy storage unit 170 is connected to the second end of the first energy storage unit 130 and the second end of the driving unit 110, respectively, and the second end of the second energy storage unit 170 is connected to the reference power source end. The first terminal of the first light emitting control unit 180 is connected to the first signal terminal 140, the second terminal of the first light emitting control unit 180 is connected to the first terminal of the driving transistor DT, the control terminal of the first light emitting control unit 180 is configured to receive a light emitting control signal, and the first light emitting control unit 180 is turned on in response to the light emitting control signal to transmit the initialization signal Vint to the first terminal of the driving unit 110 in the reset phase and transmit the first power signal VDD to the first terminal of the driving unit 110 in the light emitting phase.
The first end of the second light-emitting control unit 190 is connected to the second end of the driving unit 110, the second end of the second light-emitting control unit 190 is connected to the light-emitting element 160, the control end of the second light-emitting control unit 190 is used for receiving a light-emitting control signal, and the second light-emitting control unit 190 is turned on in response to the light-emitting control signal to transmit an initialization signal Vint to the light-emitting element 160 in a reset phase and transmit a first power signal VDD to the light-emitting element 160 in a light-emitting phase.
The light emission control signals may include a first light emission control signal and a second light emission control signal. The first light emitting control signal is connected to the control terminal of the first light emitting control unit 180. The first light emitting control signal is used to turn on the first light emitting control unit 180 in the reset phase, the compensation phase and the light emitting phase, and turn off the first light emitting control unit 180 in the data writing phase. The second light emission control signal is connected to the control terminal of the second light emission control unit 190, and is used for turning on the second light emission control unit 190 in the reset phase and the light emission phase, and turning off the second light emission control unit 190 in the compensation phase and the data writing phase.
Or the light emission control signal may include a first light emission control signal, control terminals of the first light emission control unit 180 and the second light emission control unit 190 are connected to the first light emission control signal, the first light emission control signal is used to turn on the first light emission control unit 180 and the second light emission control unit 190 in an initialization phase, a compensation phase, and a light emission phase, and turn off the first light emission control unit 180 and the second light emission control unit 190 in a data writing phase.
Each unit of the pixel driving circuit provided in the embodiment of the present disclosure will be described in detail below:
as shown in fig. 3, the driving unit 110 includes a driving transistor DT, a first terminal of the driving transistor DT is connected to the first signal terminal 140, a second terminal of the driving transistor DT is connected to the light emitting element 160, a control terminal of the driving transistor DT is connected to the second terminal of the first switching unit 120, the driving transistor DT transmits an initialization signal Vint to the light emitting element 160 in a reset phase, and transmits a first power signal VDD to the light emitting element 160 in a light emitting phase.
The first switch unit 120 includes a first transistor T1, a first end of the first transistor T1 is connected to the second signal end 150, a second end of the first transistor T1 is connected to a control end of the driving transistor DT, a control end of the first transistor T1 is connected to a scan signal Sn end, the first transistor T1 is turned on in response to the scan signal Sn during a reset period to transmit the reference signal Vref to the control end of the driving transistor DT, and the first transistor T1 is turned on in response to the scan signal Sn during a data writing period to write the data signal Vdata into the first energy storage unit 130.
The first energy storage unit 130 includes a first energy storage capacitor C1, a first end of the first energy storage capacitor C1 is connected to the control end of the driving transistor DT, and a second end of the first energy storage capacitor C1 is connected to the reference power end;
the second energy storage unit 170 includes a second energy storage capacitor C2, a first end of the second energy storage capacitor C2 is connected to a second end of the first energy storage capacitor C1 and a second end of the driving transistor DT, and a second end of the second energy storage capacitor C2 is connected to a reference power end.
In a possible embodiment, as shown in fig. 4, the first light emitting control unit 180 includes a second transistor T2, a first terminal of the second transistor T2 is connected to the first signal terminal 140, a second terminal of the second transistor T2 is connected to the first terminal of the driving transistor DT, a control terminal of the second transistor T2 is configured to receive the first light emitting control signal, and the second transistor T2 is turned on in response to the first light emitting control signal to transmit the initialization signal Vint to the first terminal of the driving unit 110 in the reset phase and transmit the first power signal VDD to the first terminal of the driving unit 110 in the light emitting phase. The second light emission control unit 190 includes a third transistor T3, a first terminal of the third transistor T3 is connected to the second terminal of the driving unit 110, a second terminal of the third transistor T3 is connected to the light emitting element 160, a control terminal of the third transistor T3 is configured to receive the second light emission control signal, and the third transistor T3 is turned on in response to the second light emission control signal to transmit the initialization signal Vint to the light emitting element 160 in the reset phase and transmit the first power signal VDD to the light emitting element 160 in the light emitting phase.
In another possible embodiment, as shown in fig. 5, the first light emitting control unit 180 includes a second transistor T2, a first terminal of the second transistor T2 is connected to the first signal terminal 140, a second terminal of the second transistor T2 is connected to the first terminal of the driving transistor DT, a control terminal of the second transistor T2 is configured to receive the first light emitting control signal, and the second transistor T2 is turned on in response to the first light emitting control signal to transmit the initialization signal Vint to the first terminal of the driving unit 110 in the reset phase and transmit the first power signal VDD to the first terminal of the driving unit 110 in the light emitting phase. The second light emission control unit 190 includes a third transistor T3, a first terminal of the third transistor T3 is connected to the second terminal of the driving unit 110, a second terminal of the third transistor T3 is connected to the light emitting element 160, a control terminal of the third transistor T3 is configured to receive the first light emission control signal, and the third transistor T3 is turned on in response to the first light emission control signal to transmit the initialization signal Vint to the light emitting element 160 in the reset phase and transmit the first power signal VDD to the light emitting element 160 in the light emitting phase.
In this example embodiment, each transistor has a control terminal, a first terminal, and a second terminal. Specifically, the control end of each transistor may be a gate, the first end may be a source, and the second end may be a drain; alternatively, the control terminal of each transistor may be a gate, the first terminal may be a drain, and the second terminal may be a source. In addition, each transistor may be an enhancement transistor or a depletion transistor, which is not particularly limited in this exemplary embodiment.
On the basis, all the transistors can be N-type thin film transistors, and the driving voltage of each transistor is high-level voltage; alternatively, all the transistors may be P-type thin film transistors, and the driving voltage of each transistor is a low level voltage.
When the light emission control signal includes the first light emission control signal and the second light emission control signal, a driving timing chart of the pixel driving circuit provided by the embodiment of the present disclosure is shown in fig. 6. The operation of the pixel driving circuit will be described in detail with reference to the operation timing chart of the pixel driving circuit shown in fig. 6. The level states of the first light emission control signal, the second light emission control signal, and the scan signal Sn at each operation stage are shown in the figure.
During the t1 period (reset phase): the first light emitting control signal is at a high level, the second light emitting control signal is at a high level, the scan signal Sn is at a high level, the first signal terminal 140 outputs the initialization signal Vint, and the second signal terminal 150 outputs the reference signal Vref. The first transistor T1, the second transistor T2, and the third transistor T3 are turned on. The reference voltage is written into the point a, at this time, the driving transistor DT operates in the linear region, and the initialization signal Vint output by the first signal terminal 140 is transmitted to the light emitting element 160, so as to realize the reset of the light emitting element 160, and avoid the phenomenon of residual image or smear of the display screen caused by the residual signal of the previous frame of screen.
During time t2 (compensation phase): the first light emitting control signal is at a high level, the second light emitting control signal is at a low level, the scan signal Sn is at a high level, the first signal terminal 140 outputs the first power signal VDD, and the second signal terminal 150 outputs the reference signal Vref. The first transistor T1 and the second transistor T2 are turned on, and the third transistor T3 is turned off. The voltage at point A is the reference voltage, and point B is charged to Vref-Vth, where Vth is the threshold voltage of the driving transistor DT.
In the period t3 (data writing stage): the first light emitting control signal is at a low level, the second light emitting control signal is at a low level, the scan signal Sn is at a high level, the first signal terminal 140 outputs the first power signal VDD, and the second signal terminal 150 outputs the data signal Vdata. The first transistor T1 is turned on, and the second and third transistors T2 and T3 are turned off. The data signal Vdata is written into the point A, the jump quantity of the voltage of the point A is Vdata-Vref, the jump quantity is transmitted to the point B through the first energy storage capacitor C1, and then the first energy storage capacitor C1 and the second energy storage capacitor C2 share the jump variable, namely the jump variable of the point B is: (Vdt-Vref). Times.C1/(C1+C2), the voltage at point B is:
at time t4 (light-emitting phase): the first light emitting control signal is at a high level, the second light emitting control signal is at a high level, the scan signal Sn is at a low level, the first signal terminal 140 outputs the first power signal VDD, and the second signal terminal 150 outputs the reference signal Vref. The first transistor T1 is turned off, the second transistor T2 and the third transistor T3 are turned off, and the driving transistor DT operates in a saturation region. Since the voltage at point B is Vb:
the driving current of the light emitting element 160 is independent of the threshold voltages of the driving transistors DT, that is, the pixel driving circuit is compensated by the first energy storage unit 130 and the second energy storage unit 170, so as to avoid the problem that the display effect of the display device is affected due to different threshold voltages of the driving transistors DT.
When the light emission control signal includes the first light emission control signal, a driving timing diagram of the pixel driving circuit provided by the embodiment of the present disclosure is shown in fig. 7. The operation of the pixel driving circuit will be described in detail with reference to the operation timing chart of the pixel driving circuit shown in fig. 7. The level states of the first light emission control signal, the second light emission control signal, and the scan signal Sn at each operation stage are shown in the figure.
During the t1 period (reset phase): the first light emitting control signal is at a high level, the scan signal Sn is at a high level, the first signal terminal 140 outputs the initialization signal Vint, and the second signal terminal 150 outputs the reference signal Vref. The first transistor T1, the second transistor T2, and the third transistor T3 are turned on. The reference voltage is written into the point a, at this time, the driving transistor DT operates in the linear region, and the initialization signal Vint output by the first signal terminal 140 is transmitted to the light emitting element 160, so as to realize the reset of the light emitting element 160, and avoid the phenomenon of residual image or smear of the display screen caused by the residual signal of the previous frame of screen.
During time t2 (compensation phase): the first light emitting control signal is at a high level, the scan signal Sn is at a high level, the first signal terminal 140 outputs the first power signal VDD, and the second signal terminal 150 outputs the reference signal Vref. The first transistor T1, the second transistor T2, and the third transistor T3 are turned on. The voltage at point A is the reference voltage, and point B is charged to Vref-Vth, where Vth is the threshold voltage of the driving transistor DT.
In the period t3 (data writing stage): the first light emitting control signal is low, the scan signal Sn is high, the first signal terminal 140 outputs the first power signal VDD, and the second signal terminal 150 outputs the data signal Vdata. The first transistor T1 is turned on, and the second and third transistors T2 and T3 are turned off. The data signal Vdata is written into the point A, the jump quantity of the voltage of the point A is Vdata-Vref, the jump quantity is transmitted to the point B through the first energy storage capacitor C1, and then the first energy storage capacitor C1 and the second energy storage capacitor C2 share the jump variable, namely the jump variable of the point B is: (Vdt-Vref). Times.C1/(C1+C2), the voltage at point B is:
at time t4 (light-emitting phase): the first light emitting control signal is high, the scan signal Sn is low, the first signal terminal 140 outputs the first power signal VDD, and the second signal terminal 150 outputs the reference signal Vref. The first transistor T1 is turned off, the second transistor T2 and the third transistor T3 are turned off, and the driving transistor DT operates in a saturation region. Since the voltage at point B is Vb:
the driving current of the light emitting element 160 is independent of the threshold voltages of the driving transistors DT, that is, the pixel driving circuit is compensated by the first energy storage unit 130 and the second energy storage unit 170, so as to avoid the problem that the display effect of the display device is affected due to different threshold voltages of the driving transistors DT.
It should be noted that: in the above specific embodiment, all the transistors are N-type transistors; those skilled in the art will readily be able to derive pixel drive circuits having all transistors that are P-type transistors from the pixel drive circuits provided in the present disclosure. In an exemplary embodiment of the present disclosure, all the transistors may be P-type transistors, in which case the first power signal VDD is a low level signal, the cathode of the OLED is connected to the second terminal of the third transistor T3, and the anode of the OLED is connected to a high level signal. The adoption of the full P-type thin film transistor has the following advantages: such as strong noise suppression; for example, the low level is on, and the low level in the charge management is easy to realize; for example, the P-type thin film transistor is simple to manufacture and relatively low in price; such as better stability of P-type thin film transistors, etc. Of course, the pixel driving circuit provided in the present disclosure may be changed to a CMOS (Complementary Metal Oxide Semiconductor ) circuit or the like, and is not limited to the pixel driving circuit provided in the present embodiment, and will not be described here again.
According to the pixel driving circuit provided by the embodiment of the disclosure, the initialization signal Vint is provided through the first signal end 140, the reference signal Vref is provided through the second signal end 150, the light-emitting element 160 can be reset in the resetting stage, the pixel driving circuit is prevented from being reset by an independent resetting unit, the number of wires in the driving circuit layer of the display device is reduced, the light transmittance of the under-screen camera area is increased, and the imaging quality of the under-screen camera is improved. The first energy storage unit 130 and the second energy storage unit 170 can compensate the driving unit 110, so as to avoid the influence of different threshold voltages of the driving transistors DT on the display effect of the display device.
The exemplary embodiments of the present disclosure also provide a driving method of a pixel driving circuit, for the above pixel driving circuit, as shown in fig. 8, the driving method includes:
step 810, using the scan signal to turn on the first switch unit, transmitting the reference signal to the control end of the driving unit, so as to turn on the driving unit to transmit the initialization signal to the light emitting element;
step S820, the first switch unit is turned on by the scanning signal, and the data signal is stored in the first energy storage unit;
in step S830, the driving unit is turned on to transmit the first power signal to the light emitting device by using the data signal in the first energy storage unit, so as to drive the light emitting device to emit light.
According to the pixel driving circuit provided by the embodiment of the disclosure, the initialization signal Vint is provided through the first signal end 140, the reference signal Vref is provided through the second signal end 150, the light-emitting element 160 can be reset in the resetting stage, the pixel driving circuit is prevented from being reset by an independent resetting unit, the number of wires in the driving circuit layer of the display device is reduced, the light transmittance of the under-screen camera area is increased, and the imaging quality of the under-screen camera is improved.
Further, when the pixel driving circuit further includes a second energy storage unit, a first light emitting control unit, and a second light emitting control unit, the driving method of the pixel driving circuit provided in the embodiment of the disclosure further includes:
in step S840, the first switching unit and the first light emitting control unit are turned on by the scan signal and the light emitting control signal, and the threshold voltage of the driving unit is written into the second terminal of the driving unit.
In step S810, the first switch unit may be turned on by the scan signal, and the reference signal is transmitted to the control terminal of the driving unit, so as to turn on the driving unit to transmit the initialization signal to the light emitting element.
The first light-emitting control signal is at a high level, the second light-emitting control signal is at a high level, the scanning signal is at a high level, the first signal end outputs an initialization signal, and the second signal end outputs a reference signal. The first transistor, the second transistor, and the third transistor are turned on. The reference voltage is written into the point A, at this time, the driving transistor works in the linear region, and the initialization signal output by the first signal end is transmitted to the light-emitting element, so that the reset of the light-emitting element is realized, and the phenomenon of image retention or smear of a display picture caused by the residual signal of the previous frame of picture is avoided.
In step S840, the first switching unit and the first light emitting control unit may be turned on using the scan signal and the light emitting control signal, and the threshold voltage of the driving unit may be written into the second terminal of the driving unit.
The first light-emitting control signal is high level, the second light-emitting control signal is low level, the scanning signal is high level, the first signal end outputs a first power signal, and the second signal end outputs a reference signal. The first transistor and the second transistor are turned on, and the third transistor is turned off. The voltage at point A is the reference voltage and point B is charged to Vref-Vth, where Vth is the threshold voltage of the drive transistor.
In step S820, the first switch unit is turned on by the scan signal to store the data signal in the first energy storage unit
The first light-emitting control signal is low level, the second light-emitting control signal is low level, the scanning signal is high level, the first signal end outputs a first power signal, and the second signal end outputs a data signal. The first transistor is on, and the second and third transistors are off. The data signal is written into the point A, at the moment, the jump quantity of the voltage of the point A is Vdata-Vref, the jump quantity is transmitted to the point B through the first energy storage capacitor, and then the first energy storage capacitor and the second energy storage capacitor share the jump quantity, namely the jump quantity of the point B is as follows: (Vdt-Vref). Times.C1/(C1+C2), the voltage at point B is:
in step S830, the driving unit may be turned on by using the data signal in the first energy storage unit to transmit the first power signal to the light emitting element, so as to drive the light emitting element to emit light.
The first light-emitting control signal is high level, the second light-emitting control signal is high level, the scanning signal is low level, the first signal end outputs a first power signal, and the second signal end outputs a reference signal. The first transistor is turned off, the second transistor and the third transistor are turned off, and the driving transistor operates in a saturation region. Since the voltage at point B is Vb:
the driving current of the light-emitting element is independent of the threshold voltage of the driving transistor, namely, the pixel driving circuit is compensated by the first energy storage unit and the second energy storage unit, so that the problem that the display effect of the display device is affected due to different threshold voltages of the driving transistors is avoided.
The above description has been made regarding the pixel driving circuit driving methods in which the light emission control signal includes the first light emission control signal and the second light emission control signal. The driving method of the pixel driving circuit when the light emission control signal includes the first light emission control signal is similar to that described above, and the embodiments of the disclosure are not repeated here.
It should be noted that although the steps of the methods of the present disclosure are illustrated in the accompanying drawings in a particular order, this does not require or imply that the steps must be performed in that particular order or that all of the illustrated steps be performed in order to achieve desirable results. Additionally or alternatively, certain steps may be omitted, multiple steps combined into one step to perform, and/or one step decomposed into multiple steps to perform, etc.
The exemplary embodiments of the present disclosure also provide a display device, as shown in fig. 9, including the first display region 210, the second display region 220, and the above-described pixel driving circuit. The first display region 210 has a light transmittance greater than that of the second display region 220; the pixel driving circuit is used for driving the light emitting elements of the first display area 210.
The first display area 210 includes a plurality of rows of first pixel units 211, and each first pixel unit 211 is correspondingly connected with a first pixel driving circuit, where the first pixel driving circuit is provided by the embodiment of the disclosure; the second display area 220 includes a plurality of rows of second pixel units 221, and each second pixel unit 221 is correspondingly connected with a second pixel driving circuit, which may be a conventional driving circuit, such as a 3T1C circuit.
On the basis, the display device further comprises: a plurality of first power lines 212 and a plurality of second power lines 222, wherein each first power line 212 is connected to a first signal terminal of a row of the first pixel circuits, and the plurality of first power lines 212 respectively receive the first power signal VDD and the initialization signal Vint. Each of the second power lines 222 is connected to a first power signal terminal of a row of the second pixel circuits, and a plurality of the second power lines 222 are connected to a first power output terminal to receive a first power signal VDD.
The first power supply signal end refers to a port for inputting a first power supply signal in the second pixel driving circuit, and the first power supply output end is a port for providing the first power supply signal for the display panel externally.
For example, the first display area may be a curved portion of a curved screen or an area where an under-screen camera is located, and so on. The first display region may include at least one light emitting element, which may be a red pixel unit, a blue pixel unit, or a green pixel unit; the second display region may include at least one light emitting element, which may be a red pixel unit, a blue pixel unit, or a green pixel unit.
Since the first display area is a small area in the whole display area, which is insensitive to the voltage drop of the first power signal, the first power lines of the light emitting elements in the first display area may be in a row design, that is, one first power line is used for one row of light emitting units in the first display area. The first power line is used for transmitting an initialization signal and a first power signal.
It should be noted that the rows exemplarily shown in the above embodiments are arranged with the first power supply line and the second power supply line for display in the manner of column scanning. In practical applications, the first power line and the second power line may also be arranged in columns, that is, used for displaying in a row scanning manner, which is not particularly limited in the embodiments of the present disclosure.
The display device provided by the embodiments of the present disclosure may be an OLED display device including a plurality of OLED light emitting elements, which may include a pixel electrode layer, a light emitting layer, and a common electrode layer. A second terminal of the driving transistor DT is connected to the pixel electrode layer.
It is understood that the display device provided by the embodiments of the present disclosure may be an LCD display device including a plurality of LCD light emitting elements including a pixel electrode layer, a liquid crystal layer, and a common electrode layer. A second terminal of the driving transistor can be connected to the pixel electrode layer
The exemplary embodiment of the disclosure also provides an electronic device, which comprises the display device.
The display device may include, for example, a mobile phone, a tablet computer, a television, a notebook computer, a digital photo frame, a navigator, and any other product or component having a display function.
As shown in fig. 10, the electronic device provided in the embodiment of the present disclosure further includes a camera 300, a frame 20, a motherboard 30, a battery 40, and a rear cover 50. Wherein the display device is mounted on the frame 20 to form a display surface of the electronic device, and the display device serves as a front case of the electronic device. The rear cover 50 is adhered to the frame by double sided tape, and the display device, the frame 20 and the rear cover 50 form an accommodating space for accommodating other electronic components or functional modules of the electronic device. Meanwhile, the display device forms a display surface of the electronic device and is used for displaying information such as images, texts and the like. The display device may be a liquid crystal display (Liquid Crystal Display) or an organic light-Emitting Diode (OLED) display.
The display device may be provided with a glass cover plate. The glass cover plate can cover the display device to protect the display device from being scratched or damaged by water.
The display device may be a full screen. At this time, the display device can display information in full screen, so that the electronic device has a large screen duty ratio. The display device includes a first display area 210 and a second display area 220. The camera 300 in the electronic device may be disposed below the first display area 210, that is, on a side of the first display area away from the light emitting side, where the first display area with high transmittance can increase the intensity of the light received by the camera 300. The camera 300 may be a front camera. Functional modules such as a proximity sensor and the like can be hidden below the display device, and a fingerprint identification module of the electronic device can be arranged on the back surface or under the screen of the electronic device.
The frame 20 may be a hollow frame structure. The material of the frame 20 may include metal or plastic. The main board 30 is installed in the accommodation space. For example, the main board 30 may be mounted on the frame 20 and stored in the storage space together with the frame 20. A grounding point is provided on the main board 30 to realize grounding of the main board 30. One or more of the functional modules of a motor, microphone, speaker, receiver, headphone interface, universal serial bus interface (USB interface), camera, proximity sensor, ambient light sensor, gyroscope, and processor may be integrated on the motherboard 30. Meanwhile, the display device may be electrically connected to the main board 30.
The main board 30 is provided with a display control circuit. The display control circuit outputs an electrical signal to the display device to control the display device to display information.
The battery 40 is mounted in the housing space. For example, the battery 40 may be mounted on the frame 20 and stored in the storage space together with the frame 20. The battery 40 may be electrically connected to the motherboard 30 to enable the battery 40 to power the electronic device. Wherein the motherboard 30 may have a power management circuit disposed thereon. The power management circuit is used to distribute the voltage provided by the battery 40 to the various electronic components in the electronic device.
The rear cover 50 is used to form the outer contour of the electronic device. The rear cover 50 may be integrally formed. In the process of forming the rear cover 50, a rear camera hole, a fingerprint recognition module mounting hole and other structures can be formed on the rear cover 50.
Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.
It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.
Claims (7)
1. A display device, characterized in that the display device comprises:
the display device comprises a first display area, a second display area and a first display unit, wherein the first display area comprises a plurality of rows of first pixel units, and each first pixel unit is correspondingly connected with a first pixel driving circuit;
the second display area comprises a plurality of rows of second pixel units, each second pixel unit is correspondingly connected with a second pixel driving circuit, and the light transmittance of the first display area is larger than that of the second display area;
a plurality of first power lines, each of which is connected to a first signal terminal of a row of the first pixel driving circuits, the plurality of first power lines respectively receiving a first power signal and an initialization signal;
a plurality of second power lines, each of which is connected to a row of the second pixel driving circuits, and the second power lines are connected to the first power output end to receive the first power signal;
the first pixel driving circuit comprises a driving unit, a first switch unit, a first energy storage unit and a second energy storage unit, wherein the driving unit comprises a first end, a second end and a control end, the first end of the driving unit is connected with a first signal end, and the second end of the driving unit is connected with a light-emitting element; the first end of the first switch unit is connected with the second signal end, the second end of the first switch unit is connected with the control end of the driving unit, and the control end of the first switch unit is connected with the scanning signal end; the first end of the first energy storage unit is connected with the control end of the driving unit; the second end of the first energy storage unit is connected with a reference power supply end; the first end of the second energy storage unit is respectively connected with the second end of the first energy storage unit and the second end of the driving unit, the second end of the second energy storage unit is connected with the reference power supply end, the first signal end is used for outputting an initialization signal in a reset phase and outputting a first power supply signal in a light-emitting phase, the second signal end is used for outputting a reference signal in a reset phase and outputting a data signal in a data writing phase, the first switch unit is turned on in response to the scanning signal in the reset phase so as to transmit the reference signal to the control end of the driving unit, and the driving unit is turned on so as to transmit the initialization signal to the light-emitting element; the first switch unit is turned on in response to the scan signal during a data writing stage to write the data signal into the first energy storage unit, and the second pixel driving circuit is different from the first pixel driving circuit.
2. The display device according to claim 1, wherein the driving unit includes:
the first end of the driving transistor is connected with the first signal end, the second end of the driving transistor is connected with the light-emitting element, the control end of the driving transistor is connected with the second end of the first switch unit, the driving transistor transmits the initialization signal to the light-emitting element in a reset stage, and transmits the first power signal to the light-emitting element in a light-emitting stage.
3. The display device according to claim 2, wherein the first switching unit includes:
the first end of the first transistor is connected with the second signal end, the second end of the first transistor is connected with the control end of the driving unit, the control end of the first transistor is connected with the scanning signal end, the first transistor is turned on in response to the scanning signal in the resetting stage so as to transmit the reference signal to the control end of the driving transistor, and the first transistor is turned on in response to the scanning signal in the data writing stage so as to write the data signal into the first energy storage unit.
4. The display device according to claim 1, wherein the first pixel driving circuit further comprises:
a first light emitting control unit, a first end of the first light emitting control unit is connected to the first signal end, a second end of the first light emitting control unit is connected to the first end of the driving unit, a control end of the first light emitting control unit is used for receiving a first light emitting control signal, the first light emitting control unit is turned on in response to the first light emitting control signal, so that the initialization signal is transmitted to the first end of the driving unit in a reset stage and the first power signal is transmitted to the first end of the driving unit in a light emitting stage;
the first end of the second light-emitting control unit is connected to the second end of the driving unit, the second end of the second light-emitting control unit is connected to the light-emitting element, the control end of the second light-emitting control unit is used for receiving a second light-emitting control signal, and the second light-emitting control unit is conducted in response to the second light-emitting control signal so as to transmit the initialization signal to the light-emitting element in a reset stage and transmit the first power signal to the light-emitting element in a light-emitting stage.
5. The display device according to claim 1, wherein the first pixel driving circuit further comprises:
a first light emitting control unit, a first end of the first light emitting control unit is connected to the first signal end, a second end of the first light emitting control unit is connected to the first end of the driving unit, a control end of the first light emitting control unit is used for receiving a first light emitting control signal, the first light emitting control unit is turned on in response to the first light emitting control signal, so that the initialization signal is transmitted to the first end of the driving unit in a reset stage and the first power signal is transmitted to the first end of the driving unit in a light emitting stage;
the first end of the second light-emitting control unit is connected to the second end of the driving unit, the second end of the second light-emitting control unit is connected to the light-emitting element, the control end of the second light-emitting control unit is used for receiving a first light-emitting control signal, and the second light-emitting control unit is conducted in response to the first light-emitting control signal so as to transmit the initialization signal to the light-emitting element in a reset stage and transmit the first power signal to the light-emitting element in a light-emitting stage.
6. An electronic device, characterized in that the electronic device comprises the display device according to any one of claims 1-5.
7. The electronic device of claim 6, further comprising a camera disposed on a side of the first display area of the display device remote from the light-emitting side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010049484.4A CN111179864B (en) | 2020-01-16 | 2020-01-16 | Pixel driving circuit, driving method thereof, display device and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010049484.4A CN111179864B (en) | 2020-01-16 | 2020-01-16 | Pixel driving circuit, driving method thereof, display device and electronic equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111179864A CN111179864A (en) | 2020-05-19 |
| CN111179864B true CN111179864B (en) | 2023-04-21 |
Family
ID=70656460
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010049484.4A Active CN111179864B (en) | 2020-01-16 | 2020-01-16 | Pixel driving circuit, driving method thereof, display device and electronic equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111179864B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113506538B (en) * | 2021-07-16 | 2022-10-04 | 深圳市华星光电半导体显示技术有限公司 | Pixel driving circuit and display panel |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101182238B1 (en) * | 2010-06-28 | 2012-09-12 | 삼성디스플레이 주식회사 | Organic Light Emitting Display and Driving Method Thereof |
| CN103440840B (en) * | 2013-07-15 | 2015-09-16 | 北京大学深圳研究生院 | A kind of display device and image element circuit thereof |
| KR102417120B1 (en) * | 2015-01-21 | 2022-07-06 | 삼성디스플레이 주식회사 | Organic Light Emitting Display Device |
| CN104715723B (en) * | 2015-03-19 | 2017-08-29 | 北京大学深圳研究生院 | Display device and its image element circuit and driving method |
| CN104778925B (en) * | 2015-05-08 | 2019-01-01 | 京东方科技集团股份有限公司 | OLED pixel circuit, display device and control method |
| CN108154840A (en) * | 2018-01-19 | 2018-06-12 | 昆山国显光电有限公司 | A kind of pixel circuit and its driving method, display device |
| CN109920371B (en) * | 2019-04-26 | 2021-01-29 | 京东方科技集团股份有限公司 | Pixel circuit, driving method thereof and display device |
| CN110459175A (en) * | 2019-08-09 | 2019-11-15 | 武汉华星光电半导体显示技术有限公司 | Display panel and display device |
| CN110649074B (en) * | 2019-09-25 | 2021-10-01 | 上海天马有机发光显示技术有限公司 | Display panel and display device |
| CN110618557A (en) * | 2019-09-30 | 2019-12-27 | 武汉天马微电子有限公司 | Display panel and display device |
-
2020
- 2020-01-16 CN CN202010049484.4A patent/CN111179864B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111179864A (en) | 2020-05-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111048041B (en) | Pixel circuit, driving method thereof, display panel and display device | |
| KR102606222B1 (en) | Display device and display panel | |
| US11328670B2 (en) | Pixel circuit, driving method thereof, and display apparatus | |
| US20190096322A1 (en) | Pixel driving circuit and method thereof, and display device | |
| EP3690871A1 (en) | Pixel circuit and driving method thereof, and display device | |
| US6864863B2 (en) | Driving circuit including organic electroluminescent element, electronic equipment, and electro-optical device | |
| US7301171B2 (en) | Display device and electronic device | |
| US6750833B2 (en) | System and methods for providing a driving circuit for active matrix type displays | |
| CN114093326A (en) | Pixel circuit and driving method thereof | |
| US20230096260A1 (en) | Display panel and electronic device | |
| US11156868B2 (en) | Charge release circuit and driving method therefor, and display device | |
| CN111179864B (en) | Pixel driving circuit, driving method thereof, display device and electronic equipment | |
| CN111754940B (en) | Pixel driving circuit, driving method thereof and display device | |
| CN114927099B (en) | Display panel, driving method thereof and display device | |
| CN113508430A (en) | Pixel circuit, display substrate and display device | |
| CN111414872B (en) | Display device and electronic apparatus | |
| CN113394258A (en) | Display panel and display device | |
| CN111210770B (en) | Pixel driving circuit, driving method thereof, display device and electronic equipment | |
| CN113409729B (en) | Pixel circuit, display panel, device and sensing driving method | |
| CN111508423B (en) | Pixel driving circuit, array substrate, display panel and display device | |
| CN112967684B (en) | Pixel circuit, driving method thereof and display device | |
| JP2005227336A (en) | Electro-optical apparatus and electronic device | |
| CN117116210A (en) | Pixel circuit, driving method, display substrate and display device | |
| CN115394227A (en) | Display panel and display device | |
| CN117577040A (en) | Display panel and display device |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |