WO2017117940A1 - 像素驱动电路、像素驱动方法、显示面板和显示装置 - Google Patents

像素驱动电路、像素驱动方法、显示面板和显示装置 Download PDF

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Publication number
WO2017117940A1
WO2017117940A1 PCT/CN2016/088381 CN2016088381W WO2017117940A1 WO 2017117940 A1 WO2017117940 A1 WO 2017117940A1 CN 2016088381 W CN2016088381 W CN 2016088381W WO 2017117940 A1 WO2017117940 A1 WO 2017117940A1
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Prior art keywords
transistor
control
pole
control module
light
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PCT/CN2016/088381
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English (en)
French (fr)
Inventor
何小祥
吴博
祁小敬
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京东方科技集团股份有限公司
成都京东方光电科技有限公司
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Priority to US15/322,463 priority Critical patent/US10403201B2/en
Publication of WO2017117940A1 publication Critical patent/WO2017117940A1/zh

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    • 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
    • G09G3/22—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 using controlled light sources
    • G09G3/30—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 using controlled light sources using electroluminescent panels
    • G09G3/32—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G09G3/3225—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
    • G09G3/3233—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the current through the light-emitting element
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    • 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
    • G09G3/22—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 using controlled light sources
    • G09G3/30—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 using controlled light sources using electroluminescent panels
    • G09G3/32—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
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    • G09G3/22—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 using controlled light sources
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    • G09G3/32—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
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    • G09G3/3225—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
    • G09G3/3258—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the voltage across the light-emitting element
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    • 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
    • G09G3/22—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 using controlled light sources
    • G09G3/30—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 using controlled light sources using electroluminescent panels
    • G09G3/32—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G09G3/3266—Details of drivers for scan electrodes
    • G—PHYSICS
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    • 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
    • G09G3/22—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 using controlled light sources
    • G09G3/30—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 using controlled light sources using electroluminescent panels
    • G09G3/32—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—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 using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G09G3/3275—Details of drivers for data electrodes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/10—OLED displays
    • H10K59/12—Active-matrix OLED [AMOLED] displays
    • H10K59/131—Interconnections, e.g. wiring lines or terminals
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    • G09G2300/0861—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
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Definitions

  • the present disclosure relates to the field of display technologies, and in particular, to a pixel driving circuit, a pixel driving method, a display panel, and a display device.
  • An Active Matrix Organic Light Emitting Diode is driven by a current generated by a driving transistor in a saturated state. Because the same gray voltage is input, different threshold voltages will generate different drive currents, resulting in current inconsistency. The uniformity of the threshold voltage Vth of the driving transistor on the low temperature polysilicon (LTPS) process is very poor, and the threshold voltage Vth also drifts, so the brightness uniformity of the conventional 2 turn-on control transistor T1C pixel unit driving circuit has been very good. difference.
  • the driving current of the driving transistor is related to the turn-on voltage of the organic light emitting diode (Organic Light-emitting control signal), and the turn-on voltage changes due to aging of the OLED, thereby The drive current of the drive transistor is affected by the aging of the OLED.
  • the main purpose of the present disclosure is to provide a pixel driving circuit, a pixel driving method, a display panel, and a display device to solve the problem that the driving current of the driving transistor cannot be controlled at the same time and the threshold voltage of the driving transistor is independent of the driving voltage of the driving transistor.
  • the current is not affected by the aging of the light-emitting elements.
  • the present disclosure provides a pixel driving circuit including a driving transistor, a storage capacitor, a turn-on control module, a write control module, and a light emission control module, wherein
  • the driving transistor the gate is connected to the first pole of the driving transistor through the turn-on control module, the first pole is connected to the first power voltage through the light-emitting control module, and the second pole is passed through the light-emitting control module Connected to the light emitting element and connected to the data line through the write control module;
  • the storage capacitor has a first end connected to a gate of the driving transistor, a second end connected to a second pole of the driving transistor by the illuminating control module, and a reference voltage is input through the write control module;
  • the turn-on control module is configured to receive an on-control signal for controlling a gate and a gate of the driving transistor under control of the turn-on control signal during a threshold compensation phase and a write phase of each display period
  • the first pole of the driving transistor is connected such that the driving transistor is diode-connected, thereby controlling a threshold voltage of the driving transistor to be written into the storage capacitor;
  • the write control module is configured to receive a scan signal for controlling a data voltage on the data line to be written into a second pole of the driving transistor under control of the scan signal in a writing phase of each display period Controlling the reference voltage to be written to the second end of the storage capacitor;
  • the illuminating control module is configured to receive an illuminating control signal for controlling the first pole of the driving transistor to be connected to the first pole in a threshold compensation phase and a illuminating and holding phase of each display period under the control of the illuminating control signal a power supply voltage that controls the second pole of the drive transistor to be coupled to the light emitting element.
  • the light emitting element comprises an organic light emitting diode
  • the organic light emitting diode the anode is connected to the second end of the storage capacitor, and the cathode is connected to the second power voltage;
  • the reference voltage is less than or equal to the second supply voltage during a write phase of each display cycle.
  • the turn-on control module includes: turning on a control transistor, the gate is connected to the turn-on control signal, the first pole is connected to the first pole of the driving transistor, and the second pole is connected to the gate of the driving transistor connection.
  • the write control module includes: a data write transistor, the gate is connected to the scan signal, the first pole is connected to the data line, and the second pole is connected to the second pole of the drive transistor;
  • the reference voltage is written to the transistor, the gate is connected to the scan signal, the first pole is connected to the second end of the storage capacitor, and the second pole is connected to the reference voltage.
  • the illuminating control module includes: a first illuminating control transistor, the gate is connected to the illuminating control signal, the first pole is connected to the first power voltage, and the second pole is connected to the first pole of the driving transistor; as well as,
  • a second light-emitting control transistor having a gate connected to the light-emitting control signal, a first pole connected to the second pole of the driving transistor, and a second pole connected to the light-emitting element.
  • the driving transistor, the turn-on control transistor, the data write transistor, the reference voltage write transistor, the first light-emitting control transistor, and the second light-emitting control transistor are all n-type transistors .
  • the illumination control signal is the scan signal;
  • the illumination control module includes: a first illumination control transistor, the gate is connected to the scan signal, and the first pole is connected to the first pole of the driving transistor, The second pole is connected to the first power voltage; and
  • a second light-emitting control transistor having a gate connected to the scan signal, a first pole connected to the light-emitting element, and a second pole connected to the second pole of the drive transistor.
  • the driving transistor, the turn-on control transistor, the data write transistor, and the reference voltage write transistor are all n-type transistors, the first light-emitting control transistor and the second light-emitting control transistor Both are p-type transistors.
  • the present disclosure also provides a pixel driving method, which is applied to the above pixel driving circuit, and the pixel driving method includes:
  • the pixel driving method includes:
  • Threshold compensation step in the threshold compensation phase of each display period, the turn-on control signal and the illumination control signal are both valid signals, the turn-on control module and the illumination control module are turned on, and the drive transistor is controlled to be diode-connected for storage. a voltage difference between the first end of the capacitor and the second end of the storage capacitor compensates a threshold voltage Vth of the driving transistor;
  • the turn-on control signal and the scan signal are both valid signals, the turn-on control module and the write control module are turned on, and the drive transistor is controlled to be connected as a diode, and the data is controlled.
  • a data voltage Vdata on the line is written to the first end of the storage capacitor through a driving transistor, and a reference voltage Vref is written to the second end of the storage capacitor;
  • the illuminating step in the illuminating and holding phase of each display period, the illuminating control signal is an effective signal, the illuminating control module is turned on, and the driving transistor is controlled to be turned on by the charge stored in the storage capacitor.
  • the light emitting element is driven to emit light.
  • the threshold compensation phase lasts less than a predetermined time.
  • the present disclosure also provides a display panel including the above-described pixel driving circuit.
  • the present disclosure also provides a display device including the above display panel.
  • the pixel driving circuit, the pixel driving method, the display panel, and the display device described in the present disclosure turn the threshold voltage Vth of the driving transistor and the data voltage Vdata on the data line by turning on the control module and the write control module.
  • Step-by-step writing to the storage capacitor so that the gate-source voltage of the driving transistor includes Vdata+Vth, thereby controlling the driving current of the driving transistor when the light-emitting holding phase is independent of the threshold voltage Vth of the driving transistor, and achieving uniform display
  • the reference voltage is also written to the second end of the storage capacitor by the write control module during the writing phase, so that the driving current of the driving transistor when the light-emitting holding phase is controlled is independent of the turn-on voltage of the light-emitting element, so that the driving transistor is driven during the light-holding phase
  • the drive current is not affected by the aging of the light-emitting elements.
  • FIG. 1 is a structural diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • FIG. 2A is a structural diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • 2B is a structural diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • 2C is a structural diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • 2D is a structural diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • 2E is a structural diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • FIG. 3 is a circuit diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • FIG. 4 is an operational timing diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • 5A is an equivalent circuit diagram of a pixel driving circuit in a threshold compensation phase t1 according to some embodiments of the present disclosure
  • 5B is an equivalent circuit diagram of the pixel driving circuit of the embodiment of the present disclosure at the writing phase t2;
  • 5C is an equivalent circuit diagram of the pixel driving circuit of the embodiment of the present disclosure in the light-emitting holding phase t3;
  • FIG. 6 is another circuit diagram of a pixel driving circuit according to some embodiments of the present disclosure.
  • FIG. 7 is another operational timing diagram of a pixel driving circuit in accordance with some embodiments of the present disclosure.
  • the pixel driving circuit of the embodiment of the present disclosure includes a driving transistor DTFT, a storage capacitor C1, a turn-on control module 11, a write control module 12, and a light emission control module 13, wherein
  • the gate of the driving transistor DTFT is connected to the first pole of the driving transistor DTFT through the turn-on control module 11, and the first pole is connected to the first power voltage V1 through the light-emitting control module 13, and the second pole passes
  • the light emission control module 12 is connected to the light emitting element LE and connected to the data line Data through the write control module 12;
  • the storage capacitor C1 has a first end A connected to the gate of the driving transistor DTFT, and a second end B connected to the second pole of the driving transistor DTFT through the illumination control module 12 and controlled by the write Module 12 is connected to a reference voltage Vref;
  • the switch-on control module 11 is configured to access the turn-on control signal CR for controlling the drive transistor DTFT under the control of the turn-on control signal CR during a threshold compensation phase and a write phase of each display cycle.
  • the gate is coupled to the first electrode of the driving transistor DTFT, such that the driving transistor DTFT is diode-connected, thereby controlling the threshold voltage Vth of the driving transistor DTFT is written into the storage capacitor C1;
  • the write control module 12 is configured to access a scan signal Scan for controlling the data voltage Vdata on the data line Data to be written to the drive under the control of the scan signal Scan during a write phase of each display cycle.
  • a second pole of the transistor DTFT, controlling the reference voltage Vref is written to the second end B of the storage capacitor C1;
  • the illumination control module 13 is configured to access the illumination control signal Em for controlling the first polarity of the driving transistor DTFT under the control of the illumination control signal Em during the threshold compensation phase and the illumination retention phase of each display period.
  • the second pole of the driving transistor DTFT is controlled to be connected to the light emitting element LE.
  • the pixel driving circuit of the embodiment of the present disclosure writes the threshold voltage Vth of the driving transistor and the data voltage Vdata of the data line to the storage capacitor step by step by the turn-on control module and the write control module, thereby causing the gate of the driving transistor
  • the source voltage includes Vdata+Vth, so that the driving current of the driving transistor when controlling the light-emitting holding phase is independent of the threshold voltage Vth of the driving transistor, and the display is uniform.
  • the pixel driving circuit of the embodiment of the present disclosure further writes a reference voltage to the second end of the storage capacitor in the writing phase by the write control module, so that the driving current of the driving transistor and the turning of the light emitting element when the light emitting holding phase can be controlled
  • the voltage is independent so that the driving current of the driving transistor at the light-holding stage is not affected by the aging of the light-emitting element.
  • the driving transistor DTFT is an n-type transistor.
  • the first electrode of the driving transistor DTFT drives the drain of the transistor DTFT
  • the second electrode of the driving transistor DTFT drives the source of the transistor DTFT; however, in practice In operation, the driving transistor DTFT may also be a p-type transistor.
  • the present disclosure is as shown in FIG. 1 when the pixel driving circuit is in operation
  • the illumination control module 13 controls the drain of the V1 write drive transistor DTFT, controls the source of the drive transistor DTFT to be connected to the light emitting element LE; and the turn-on control module 11 controls the drive transistor DTFT.
  • the gate is connected to the drain of the driving transistor DTFT, that is, the driving transistor DTFT is diode-connected, the driving transistor DTFT enters a saturated state, and the gate-source voltage of the driving transistor DTFT is a threshold voltage Vth, and the first terminal A voltage is V1, and the second The voltage of the terminal B is V1-Vth, the voltage difference between the first end A of the storage capacitor C1 and the second end B of the storage capacitor C1 is the threshold voltage Vth, so that the threshold voltage Vth of the control transistor is controlled to be written into the storage capacitor C1;
  • the light emission control module 13 controls the connection between the drain of the driving transistor DTFT and the first power voltage line that outputs the first power voltage V1, and controls the source of the driving TFT DTFT to be turned off.
  • the write control module 12 controls the write of the Vdata write drive transistor DTFT
  • the first terminal A voltage is Vdata+Vth
  • the write control module 12 controls the second terminal B voltage to be pulled down to the reference voltage Vref, the first end A of the storage capacitor C1 and the second end B of the storage capacitor C1.
  • the voltage difference between the voltage is Vdata+Vth-Vref, the threshold voltage Vth of the driving transistor and the data voltage Vdata are written into the storage capacitor C1.
  • the reference voltage Vref can clear the light-emitting element LE of the previous frame connected to the source of the driving transistor DTFT.
  • the illumination control module 13 controls the drain of the driving transistor DTFT to access the first power voltage V1 and controls the sources of the driving transistor DTFT and the second end B of the light emitting element LE and the storage capacitor C1, respectively.
  • the turn-on control module 11 controls the connection between the gate of the drive transistor DTFT and the drain of the drive transistor DTFT
  • the write control module 12 controls the second terminal B of the storage capacitor C1 to stop the reference voltage Vref and control Disconnecting the connection between the source of the driving transistor DTFT and Data, so that the gate-source voltage Vgs of the driving transistor DTFT is the voltage difference between the first terminal A of the storage capacitor C1 and the second terminal B of the storage capacitor C1 due to The voltage difference across the storage capacitor C1 cannot be abruptly changed. Therefore, the voltage difference between the first terminal A of the storage capacitor C1 and the second terminal B of the storage capacitor C1 is still Vdata+Vth-Vref, thereby controlling the driving of the driving transistor DTFT.
  • the current is independent of the threshold voltage Vth of the driving transistor DTFT;
  • the source of the driving transistor DTFT is written in the writing phase reference voltage Vref, thereby avoiding the source voltage of the driving transistor DTFT being the turn-on voltage of the light-emitting element LE
  • the gate-source voltage of the driving transistor DTFT is related to the turn-on voltage of the LE at the light-holding stage, so that the driving current of the driving transistor DTFT in the light-holding phase is independent of the turn-on voltage of the light-emitting element LE, so that the driving current It is not affected by the aging of the light-emitting elements.
  • the source of the driving transistor DTFT is not written in the writing phase by the reference voltage Vref, but the second terminal B of the storage capacitor C1 is directly connected to the light-emitting element LE, the first portion of the storage capacitor C1 is written in the writing phase.
  • the voltage VB of the two terminals B is the turn-on voltage Vle of the light-emitting element LE, and the voltage difference between the first end A of the storage capacitor C1 and the second end B of the storage capacitor C1 is Vdata+Vth-Vle, due to the storage capacitor C1
  • the voltage difference between the terminals cannot be abruptly changed, and the voltage difference between the first terminal A of the storage capacitor C1 and the second terminal B of the storage capacitor C1 is maintained at Vdata+Vth-Vle during the light-emitting holding phase, so that the driving transistor drives the light-emitting element to emit light.
  • the drive current is related to the turn-on voltage of the light-emitting element, which is affected by the aging of the light-emitting element.
  • the light emitting element may include an organic light emitting diode OLED;
  • the organic light emitting diode OLED the anode is connected to the second end of the storage capacitor C1, and the cathode is connected to the second power voltage V2;
  • the reference voltage Vref is less than or equal to the second power voltage V2, thereby controlling the organic light emitting diode OLED not to emit light during the writing phase to extend the life of the OLED.
  • the threshold compensation phase lasts for less than a predetermined time
  • the light-emitting element is driven by the driving transistor in a saturated state during the threshold compensation phase, in order to reduce the influence of the display effect, it is necessary to minimize the duration of the threshold compensation phase.
  • the turn-on control module includes: turning on the control transistor T1, the gate accessing the turn-on control signal CR, the first pole being connected to the first pole of the driving transistor DTFT, and second a pole connected to a gate of the driving transistor DTFT;
  • the turn-on control transistor T1 is an n-type transistor.
  • the write control module includes: a data write transistor T2, a gate access scan signal Scan, a first pole connected to the data line Data, a second pole and the drive transistor The second pole connection of the DTFT; and,
  • the reference voltage is written to the transistor T3, the gate is connected to the scan signal Scan, the first pole is connected to the second end of the storage capacitor Cs, and the second pole is connected to the reference voltage Vref;
  • the data writing transistor T2 and the reference voltage writing transistor T3 are both n-type transistors.
  • the illumination control module may include:
  • a first light-emitting control transistor T4 the gate is connected to the light-emission control signal Em, the first pole is connected to the first power voltage V1, and the second pole is connected to the first pole of the driving transistor DTFT;
  • a second light-emitting control transistor T5 the gate is connected to the light-emission control signal Em, the first pole is connected to the second pole of the driving transistor DTFT, and the second pole is connected to the anode of the organic light-emitting diode OLED;
  • the first light emission control transistor T4 and the second light emission control transistor T5 are both n-type transistors.
  • the illumination control signal Em is a scan signal Scan
  • the illuminating control module includes: a first illuminating control transistor T4, the gate is connected to the scan signal Scan, a first pole is connected to a first pole of the driving transistor DTFT, and a second pole is connected to the first power voltage V1; and,
  • the second light-emitting control transistor T5 has a gate connected to the scan signal Scan, a first pole connected to the anode of the organic light-emitting diode OLED, and a second pole connected to the second pole of the driving transistor DTFT.
  • the first illumination control transistor and the second illumination control transistor are both p-type transistors.
  • the transistors employed in all embodiments of the present disclosure may each be a thin film transistor or a field effect transistor or other device having the same characteristics.
  • the two poles except the gate are referred to as a first pole and a second pole, wherein the first pole and the second pole may be interchanged as the current flow direction changes, that is, The first extreme source, the second extreme drain, or the first extreme drain, the second extreme source.
  • the transistor employed in the embodiment of the present disclosure may be an n-type transistor or a p-type transistor in accordance with the characteristics of the transistor.
  • the pixel driving circuit described in the present disclosure will be described below based on two specific embodiments.
  • the pixel driving circuit includes a driving transistor DTFT, a storage capacitor C1, a turn-on control module, a write control module, and a light emission control module;
  • the first end A of the storage capacitor is connected to the gate of the driving transistor DTFT;
  • the turn-on control module includes: a turn-on control transistor T1, a gate access-on control signal CR, a drain connected to a drain of the drive transistor DTFT, and a source connected to a gate of the drive transistor DTFT;
  • the write control module includes: a data write transistor T2, a gate connected to the scan signal Scan, a drain connected to the data line Data of the output data voltage Vdata, and a source connected to the source of the drive transistor DTFT;
  • the reference voltage is written to the transistor T3, the gate is connected to the scan signal Scan, the first pole is connected to the second end B of the storage capacitor C1, and the second pole is connected to the reference voltage Vref;
  • the illuminating control module includes: a first illuminating control transistor T4, the gate is connected to the illuminating control signal Em, the first pole is connected to the high level VDD, and the second pole is connected to the drain of the driving transistor DTFT;
  • a second light-emitting control transistor T5 the gate is connected to the light-emitting control signal Em, the first pole is connected to the source of the driving transistor DTFT, and the second pole is connected to the anode of the organic light-emitting diode OLED;
  • the cathode of the organic light emitting diode OLED is connected to a low level VSS;
  • the driving transistor DTFT, the turn-on control transistor T1, the data write transistor T2, the reference voltage write transistor T3, the first light-emitting control transistor T4, and the second light-emitting control transistor T5 are N-type transistor.
  • the pixel drive circuit of the present disclosure as shown in FIG. 3 is in operation.
  • the on control signal CR and the illumination control signal Em are both at a high level
  • the scan signal Scan is at a low level
  • the control transistor T1 the first illumination control transistor T4, and the second illumination control transistor T5 are both turned on.
  • the data writing transistor T2 and the reference voltage writing transistor T3 are both turned off.
  • the driving transistor DTFT is diode-connected, the driving transistor DTFT is in a saturated state, and the gate-source voltage Vgs of the driving transistor DTFT is the driving transistor DTFT.
  • the threshold voltage Vth the voltage of the first terminal A is a high level VDD, the voltage of the second terminal B is VDD-Vth, and the voltage difference between the first end A of the storage capacitor C1 and the second end B of the storage capacitor C1 is Threshold voltage Vth, the threshold voltage Vth of the driving transistor DTFT is written into the storage capacitor C1;
  • the turn-on control signal CR and the scan signal Scan are both at a high level
  • the light-emission control signal Em is at a low level
  • the turn-on control transistor T1, the data write transistor T2, and the reference voltage write transistor T3 are both turned on.
  • the first light-emitting control transistor T4 and the second light-emission control transistor T5 are both turned off. As shown in FIG.
  • the driving transistor DTFT maintains a diode connection, and the gate of the driving transistor DTFT
  • the source voltage Vgs is the threshold voltage Vth
  • the source of the driving transistor DTFT is connected to the data voltage Vdata, so the voltage of the first terminal A is Vdata+Vth, and the voltage of the second terminal B is pulled down to the reference voltage Vref, thus the storage capacitor C1
  • the voltage difference between the first terminal A and the second terminal B of the storage capacitor C1 is Vdata+Vth-Vref
  • the threshold voltage Vth of the driving transistor DTFT and the data voltage Vdata are written into the storage capacitor C1, and the reference voltage Vref can be cleared.
  • the turn-on control signal CR and the scan signal Scan are both at a low level
  • the light-emission control signal Em is at a high level
  • the turn-on control transistor T1, the reference voltage write transistor T3, and the reference voltage write transistor T3 are both turned on.
  • the first light-emitting control transistor T4 and the second light-emitting control transistor T5 are turned on, as shown in FIG. 5C
  • the voltage of the first terminal A of the storage capacitor C1 drives the driving transistor DTFT to start the OLED, and the second of the storage capacitor C1.
  • the current flowing through the OLED ie, the driving current of the driving transistor DTFT I is as follows:
  • the OLED remains in an illuminating state, and the current flowing through the OLED in the illuminating holding phase t3 is independent of the threshold voltage Vth, so that the uniformity of the current can be improved, thereby achieving uniform display brightness.
  • the pixel driving circuit described in the present disclosure as shown in FIG. 3 does not include the reference voltage writing transistor T3, that is, without writing the reference voltage Vref to the second end B of the storage capacitor C1 in the writing phase t2, then
  • the voltage of the second end of the storage capacitor C1 is the turn-on voltage Voled of the OLED, so that the gate-source voltage of the driving transistor DTFT in the light-holding stage t3 is related to the turn-on voltage Voled of the OLED, since the voltage is turned on as the OLED ages.
  • the capacitor C1 is stored in the writing phase.
  • the voltage VB of the second terminal B is the turn-on voltage Voled of the OLED, and the storage voltage is
  • the voltage difference between the first end A of the capacitor C1 and the second end B of the storage capacitor C1 is Vdata+Vth-Voled. Since the voltage difference across the storage capacitor C1 cannot be abruptly changed, the capacitor C1 is stored in the illuminating holding phase.
  • the voltage difference between the one end A and the second end B of the storage capacitor C1 is maintained as Vdata+Vth-Voled, so that the driving current for driving the OLED to drive the OLED is related to the turn-on voltage Voled of the OLED, and the driving current will be Affected by aging of OLEDs.
  • another pixel driving circuit described in the present disclosure includes a driving transistor DTFT, a storage capacitor C1, a turn-on control module, a write control module, and a light emission control module;
  • the first end A of the storage capacitor is connected to the gate of the driving transistor DTFT;
  • the turn-on control module includes: a turn-on control transistor T1, a gate access-on control signal CR, a drain connected to a drain of the drive transistor DTFT, and a source connected to a gate of the drive transistor DTFT;
  • the write control module includes:
  • the data is written into the transistor T2, the gate is connected to the scan signal Scan, the drain is connected to the data line Data of the output data voltage Vdata, and the source is connected to the source of the drive transistor DTFT;
  • the reference voltage is written to the transistor T3, the gate is connected to the scan signal Scan, the first pole is connected to the second end B of the storage capacitor C1, and the second pole is connected to the reference voltage Vref;
  • the illumination control module includes:
  • a first light-emitting control transistor T4 a gate connected to the scan signal Scan, a source connected to a drain of the driving transistor DTFT, and a drain connected to a high level VDD;
  • a second light-emitting control transistor T5 the gate is connected to the scan signal Scan, the source is connected to the anode of the organic light-emitting diode OLED, and the drain is connected to the source of the drive transistor DTFT;
  • the driving transistor DTFT, the turn-on control transistor T1, the data write transistor T2, and the reference voltage write transistor T3 are all n-type transistors, the first light-emitting control transistor T4 and the second light-emitting Control transistor T5 is a p-type transistor.
  • the turn-on control signal CR is at a high level
  • the scan signal Scan is at a low level
  • the first light-emission control transistor T4, and the second light-emission control transistor T5 are both turned on, and the data is written into the transistor.
  • T2 and the reference voltage writing transistor T3 are both turned off, the driving transistor DTFT is diode-connected, the driving transistor DTFT enters a saturated state, and the gate of the driving transistor DTFT is driven.
  • the source voltage Vgs is the threshold voltage Vth of the driving transistor DTFT
  • the voltage of the first terminal A is a high level VDD
  • the voltage of the second terminal B is VDD-Vth
  • the voltage difference between the terminals B is the threshold voltage Vth
  • the threshold voltage Vth of the driving transistor DTFT is written into the storage capacitor C1;
  • the turn-on control signal CR and the scan signal Scan are both at a high level, and the turn-on control transistor T1, the data write transistor T2, and the reference voltage write transistor T3 are both turned on, the first light-emission control transistor T4 and the first The second light-emitting control transistor T5 is turned off. As shown in FIG.
  • the driving transistor DTFT maintains a diode connection
  • the gate-source voltage Vgs of the driving transistor DTFT is a threshold voltage Vth
  • the source of the driving transistor DTFT is connected to the data voltage Vdata, so the first end The voltage of A is Vdata+Vth
  • the voltage of the second terminal B is pulled down to the reference voltage Vref, so the voltage difference between the first end A of the storage capacitor C1 and the second end B of the storage capacitor C1 is Vdata+Vth-Vref
  • the threshold voltage Vth and the data voltage Vdata of the driving transistor DTFT are written into the storage capacitor C1, and the reference voltage Vref can clear the anode voltage of the previous frame OLED;
  • the turn-on control signal CR and the scan signal Scan are both at a low level, and the turn-on control transistor T1, the reference voltage write transistor T3, and the reference voltage write transistor T3 are both turned off, the first light-emission control transistor T4 and The second light-emitting control transistor T5 is turned on.
  • the voltage of the first terminal A of the storage capacitor C1 drives the driving transistor DTFT to cause the OLED to start to emit light
  • the voltage VB of the second terminal B of the storage capacitor C1 is the opening of the OLED.
  • the current flowing through the OLED ie, the driving current of the driving transistor DTFT I is as follows:
  • the OLED remains in an illuminating state, and the current flowing through the OLED in the illuminating holding phase t3 is independent of the threshold voltage Vth, so that the uniformity of the current can be improved, thereby achieving uniform display brightness.
  • the pixel driving circuit shown in FIG. 6 does not include the reference voltage writing transistor T3, that is, the second end B of the storage capacitor C1 is not controlled by the reference voltage Vref during the writing phase t2, the second of the storage capacitor C1
  • the voltage of the terminal is the turn-on voltage Voled of the OLED, so that the gate-source voltage of the driving transistor DTFT in the light-holding stage t3 is related to the turn-on voltage Voled of the OLED.
  • the Voled will change, so that the current flowing through the OLED will be affected by the aging of the OLED, and the pixel driving current described in the embodiments of the present disclosure is controlled in the writing phase by using the write control module.
  • the voltage Vref is written to the second end of the storage capacitor C1 (the reference voltage is applied to the transistor T3 in FIG. 6), so that the above situation can be avoided.
  • the pixel driving method of the embodiment of the present disclosure is applied to the pixel driving circuit described above, and the pixel driving method includes:
  • Threshold compensation step in the threshold compensation phase of each display period, the on control signal and the illumination control signal are both valid signals (the effective signal is a signal for controlling the corresponding module to be turned on), and the control module and the illumination control module are turned on. Turning on, controlling the driving transistor to be a diode connection to compensate a threshold voltage Vth of the driving transistor by a voltage difference between a first end of the storage capacitor and a second end of the storage capacitor;
  • the turn-on control signal and the scan signal are both valid signals, the turn-on control module and the write control module are turned on, and the drive transistor is controlled to be connected as a diode, and the data is controlled.
  • the data voltage Vdata on the line is written to the first end of the storage capacitor through a driving transistor, and the reference voltage Vref is written to the second end of the storage capacitor;
  • the illuminating step in the illuminating holding phase of each display period, the illuminating control signal is an effective signal, and the illuminating control module is turned on, and the driving transistor is controlled to be turned on by the charge stored in the storage capacitor to drive the illuminating element to emit light.
  • the pixel driving method of the embodiment of the present disclosure writes the threshold voltage Vth of the driving transistor and the data voltage Vdata of the data line to the storage capacitor step by step by the turn-on control module and the write control module, thereby causing the gate of the driving transistor
  • the source voltage includes Vdata+Vth, so that the driving current of the driving transistor when controlling the light-emitting holding phase is independent of the threshold voltage Vth of the driving transistor, and the display is uniform.
  • the pixel driving circuit of the embodiment of the present disclosure further writes a reference voltage to the second end of the storage capacitor in the writing phase by the write control module, so that the driving current of the driving transistor and the turning of the light emitting element when the light emitting holding phase can be controlled
  • the voltage is independent so that the driving current of the driving transistor at the light-holding stage is not affected by the aging of the light-emitting element.
  • the threshold compensation phase lasts for less than a predetermined time
  • the light-emitting element is driven by the driving transistor in a saturated state during the threshold compensation phase, in order to reduce the influence of the display effect, it is necessary to minimize the duration of the threshold compensation phase.
  • the display panel described in the embodiments of the present disclosure includes the pixel driving circuit described above.
  • the display device described in the embodiments of the present disclosure includes the above display panel.
  • the display device may be, for example, an electronic paper, an OLED display device, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital frame, a navigator, or the like, or any product or component having a display function.

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Abstract

一种像素驱动电路、像素驱动方法、显示面板和显示装置。像素驱动电路包括驱动晶体管（DTFT）、存储电容（C1）、接通控制模块（11）、写入控制模块（12）和发光控制模块（13），其中接通控制模块（11）在阈值补偿阶段和写入阶段控制驱动晶体管（DTFT）的栅极和驱动晶体管（DTFT）的第一极连接，使所述驱动晶体管（DTFT）的阈值电压（Vth）写入所述存储电容（C1）；写入控制模块（12）在写入阶段控制数据电压（Vdata）写入驱动晶体管（DTFT）的第二极。通过接通控制模块（11）和写入控制模块（12）分步写入驱动晶体管（DTFT）的阈值电压（Vth）和数据线上的数据电压（Vdata）至存储电容（C1），控制驱动晶体管（DTFT）的驱动电流与驱动晶体管（DTFT）的阈值电压无关，还通过写入控制模块（12）在写入阶段将参考电压（Vref）写入存储电容（C1）的第二端（B），控制发光保持阶段时驱动晶体管（DTFT）的驱动电流与发光元件（LE）的开启电压无关。

Description

像素驱动电路、像素驱动方法、显示面板和显示装置
相关申请的交叉引用
本申请主张在2016年1月4日在中国提交的中国专利申请No.201610005028.3的优先权，其全部内容通过引用包含于此。
技术领域
本公开文本涉及显示技术领域，尤其涉及一种像素驱动电路、像素驱动方法、显示面板和显示装置。
背景技术
有源矩阵有机发光二极管(Active Matrix Organic Light Emitting Diode，AMOLED)是由驱动晶体管在饱和状态时产生的电流驱动发光的。因为输入相同的灰阶电压时，不同的临界电压会产生不同的驱动电流，造成电流的不一致性。低温多晶硅(Low Temperature Poly Silicon，LTPS)制程上驱动晶体管的阈值电压Vth的均匀性非常差，同时该阈值电压Vth也有漂移，因此传统的2接通控制晶体管T1C像素单元驱动电路亮度均匀性一直很差。并且采用相关技术中的像素驱动电路，驱动晶体管的驱动电流与有机发光二极管(Organic Light-发光控制信号Emitting Diode，OLED)的开启电压有关，由于随着OLED的老化该开启电压会改变，从而使得驱动晶体管的驱动电流受到OLED的老化的影响。
发明内容
本公开文本的主要目的在于提供一种像素驱动电路、像素驱动方法、显示面板和显示装置，以解决相关技术中无法同时控制驱动晶体管的驱动电流与驱动晶体管的阈值电压无关与控制驱动晶体管的驱动电流不受发光元件老化影响的问题。
为了达到上述目的，本公开文本提供了一种像素驱动电路，包括驱动晶体管、存储电容、接通控制模块、写入控制模块和发光控制模块，其中，
所述驱动晶体管，栅极通过所述接通控制模块与所述驱动晶体管的第一极连接，第一极通过所述发光控制模块接入第一电源电压，第二极通过所述发光控制模块与发光元件连接并通过所述写入控制模块与数据线连接；
所述存储电容，第一端与所述驱动晶体管的栅极连接，第二端通过所述发光控制模块与所述驱动晶体管的第二极连接并通过所述写入控制模块接入参考电压；
所述接通控制模块，接入接通控制信号，用于在每一显示周期的阈值补偿阶段和写入阶段，在所述接通控制信号的控制下控制所述驱动晶体管的栅极和所述驱动晶体管的第一极连接，以使得所述驱动晶体管为二极管连接，从而控制所述驱动晶体管的阈值电压写入所述存储电容；
所述写入控制模块，接入扫描信号，用于在每一显示周期的写入阶段在所述扫描信号的控制下控制所述数据线上的数据电压写入所述驱动晶体管的第二极，控制所述参考电压写入所述存储电容的第二端；以及
所述发光控制模块，接入发光控制信号，用于在每一显示周期的阈值补偿阶段和发光保持阶段在所述发光控制信号的控制下控制所述驱动晶体管的第一极接入所述第一电源电压，控制所述驱动晶体管的第二极与所述发光元件连接。
实施时，所述发光元件包括有机发光二极管；
所述有机发光二极管，阳极与所述存储电容的第二端连接，阴极接入第二电源电压；
在每一显示周期的写入阶段，所述参考电压小于或等于所述第二电源电压。
实施时，所述接通控制模块包括：接通控制晶体管，栅极接入接通控制信号，第一极与所述驱动晶体管的第一极连接，第二极与所述驱动晶体管的栅极连接。
实施时，所述写入控制模块包括：数据写入晶体管，栅极接入扫描信号，第一极与所述数据线连接，第二极与所述驱动晶体管的第二极连接；以及，
参考电压写入晶体管，栅极接入所述扫描信号，第一极与所述存储电容的第二端连接，第二极接入所述参考电压。
实施时，所述发光控制模块包括：第一发光控制晶体管，栅极接入发光控制信号，第一极接入所述第一电源电压，第二极与所述驱动晶体管的第一极连接；以及，
第二发光控制晶体管，栅极接入所述发光控制信号，第一极与所述驱动晶体管的第二极连接，第二极与所述发光元件连接。
实施时，所述驱动晶体管、所述接通控制晶体管、所述数据写入晶体管、所述参考电压写入晶体管、所述第一发光控制晶体管和所述第二发光控制晶体管都为n型晶体管。
实施时，所述发光控制信号为所述扫描信号；所述发光控制模块包括：第一发光控制晶体管，栅极接入所述扫描信号，第一极与所述驱动晶体管的第一极连接，第二极接入所述第一电源电压；以及，
第二发光控制晶体管，栅极接入所述扫描信号，第一极与所述发光元件连接，第二极与所述驱动晶体管的第二极连接。
实施时，所述驱动晶体管、所述接通控制晶体管、所述数据写入晶体管和所述参考电压写入晶体管都为n型晶体管，所述第一发光控制晶体管和所述第二发光控制晶体管都为p型晶体管。
本公开文本还提供了一种像素驱动方法，应用于上述的像素驱动电路，所述像素驱动方法包括：
所述像素驱动方法包括：
阈值补偿步骤：在每一显示周期的阈值补偿阶段，接通控制信号和发光控制信号都为有效信号，接通控制模块和发光控制模块导通，控制所述驱动晶体管为二极管连接，以通过存储电容的第一端和存储电容的第二端之间的电压差补偿所述驱动晶体管的阈值电压Vth；
写入步骤：在每一显示周期的写入阶段，接通控制信号和扫描信号都为有效信号，接通控制模块和写入控制模块导通，控制所述驱动晶体管保持为二极管连接，将数据线上的数据电压Vdata通过驱动晶体管写入所述存储电容的第一端，将参考电压Vref写入所述存储电容的第二端；以及
发光步骤：在每一显示周期的发光保持阶段，发光控制信号为有效信号，发光控制模块导通，通过所述存储电容中存储的电荷控制驱动晶体管导通以 驱动发光元件发光。
实施时，所述阈值补偿阶段持续的时间小于预定时间。
本公开文本还提供了一种显示面板，包括上述的像素驱动电路。
本公开文本还提供了一种显示装置，包括上述的显示面板。
与相关技术相比，本公开文本所述的像素驱动电路、像素驱动方法、显示面板和显示装置通过接通控制模块和写入控制模块将驱动晶体管的阈值电压Vth和数据线上的数据电压Vdata分步写入至存储电容，从而使得驱动晶体管的栅源电压包含Vdata+Vth，从而控制发光保持阶段时驱动晶体管的驱动电流与驱动晶体管的阈值电压Vth无关，达到显示均匀的目的，本公开文本还通过写入控制模块在写入阶段将参考电压写入存储电容的第二端，从而可以控制发光保持阶段时驱动晶体管的驱动电流与发光元件的开启电压无关，以使得发光保持阶段时驱动晶体管的驱动电流不受发光元件的老化的影响。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本申请中记载的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。以下附图并未刻意按实际尺寸等比例缩放绘制，重点在于示出本申请的主旨。
图1是本公开文本一些实施例所述的像素驱动电路的结构图；
图2A是本公开文本一些实施例所述的像素驱动电路的结构图；
图2B是本公开文本一些实施例所述的像素驱动电路的结构图；
图2C是本公开文本一些实施例所述的像素驱动电路的结构图；
图2D是本公开文本一些实施例所述的像素驱动电路的结构图；
图2E是本公开文本一些实施例所述的像素驱动电路的结构图；
图3是本公开文本一些实施例所述的像素驱动电路的一个电路图；
图4是本公开文本一些实施例所述的像素驱动电路的工作时序图；
图5A是本公开文本一些实施例所述的像素驱动电路的在阈值补偿阶段t1的等效电路图；
图5B是本公开文本一些实施例所述的像素驱动电路的在写入阶段t2的等效电路图；
图5C是本公开文本一些实施例所述的像素驱动电路的在发光保持阶段t3的等效电路图；
图6是本公开文本一些实施例所述的像素驱动电路的另一个电路图；以及
图7是本公开文本一些实施例所述的像素驱动电路的另一个工作时序图。
具体实施方式
为使本公开文本实施例的目的、技术方案和优点更加清楚，下面将结合本公开文本实施例的附图，对本公开文本实施例的技术方案进行清楚、完整地描述。显然，所描述的实施例是本公开文本的一部分实施例，而不是全部的实施例。基于所描述的本公开文本的实施例，本领域普通技术人员所获得的所有其他实施例，都属于本公开文本保护的范围。
除非另作定义，此处使用的技术术语或者科学术语应当为本公开所属领域内具有一般技能的人士所理解的通常意义。本公开专利申请说明书以及权利要求书中使用的“第一”、“第二”以及类似的词语并不表示任何顺序、数量或者重要性，而只是用来区分不同的组成部分。同样，“一个”或者“一”等类似词语也不表示数量限制，而是表示存在至少一个。“连接”或者“相连”等类似的词语并非限定于物理的或者机械的连接，而是可以包括电性的连接，不管是直接的还是间接的。“上”、“下”、“左”、“右”等仅用于表示相对位置关系，当被描述对象的绝对位置改变后，则该相对位置关系也相应地改变。
如图1所示，本公开文本实施例所述的像素驱动电路包括驱动晶体管DTFT、存储电容C1、接通控制模块11、写入控制模块12和发光控制模块13，其中，
所述驱动晶体管DTFT，栅极通过所述接通控制模块11与所述驱动晶体管DTFT的第一极连接，第一极通过所述发光控制模块13接入第一电源电压V1，第二极通过所述发光控制模块12与发光元件LE连接并通过所述写入控制模块12与数据线Data连接；
所述存储电容C1，第一端A与所述驱动晶体管DTFT的栅极连接，第二端B通过所述发光控制模块12与所述驱动晶体管DTFT的第二极连接并通过所述写入控制模块12接入参考电压Vref；
所述接通控制模块11，接入接通控制信号CR，用于在每一显示周期的阈值补偿阶段和写入阶段，在所述接通控制信号CR的控制下控制所述驱动晶体管DTFT的栅极和所述驱动晶体管DTFT的第一极连接，以使得所述驱动晶体管DTFT为二极管连接，从而控制所述驱动晶体管DTFT的阈值电压Vth写入所述存储电容C1；
所述写入控制模块12，接入扫描信号Scan，用于在每一显示周期的写入阶段在所述扫描信号Scan的控制下控制所述数据线Data上的数据电压Vdata写入所述驱动晶体管DTFT的第二极，控制所述参考电压Vref写入所述存储电容C1的第二端B；
所述发光控制模块13，接入发光控制信号Em，用于在每一显示周期的阈值补偿阶段和发光保持阶段在所述发光控制信号Em的控制下控制所述驱动晶体管DTFT的第一极接入所述第一电源电压V1，控制所述驱动晶体管DTFT的第二极与所述发光元件LE连接。
本公开文本实施例所述的像素驱动电路通过接通控制模块和写入控制模块将驱动晶体管的阈值电压Vth和数据线上的数据电压Vdata分步写入至存储电容，从而使得驱动晶体管的栅源电压包含Vdata+Vth，从而控制发光保持阶段时驱动晶体管的驱动电流与驱动晶体管的阈值电压Vth无关，达到显示均匀的目的。本公开文本实施例所述的像素驱动电路还通过写入控制模块在写入阶段将参考电压写入存储电容的第二端，从而可以控制发光保持阶段时驱动晶体管的驱动电流与发光元件的开启电压无关，以使得发光保持阶段时驱动晶体管的驱动电流不受发光元件的老化的影响。
具体地，在图1中，驱动晶体管DTFT为n型晶体管，此时，驱动晶体管DTFT的第一极为驱动晶体管DTFT的漏极，驱动晶体管DTFT的第二极为驱动晶体管DTFT的源极；然而在实际操作时，驱动晶体管DTFT也可以为p型晶体管。
本公开文本如图1所示的像素驱动电路在工作时，
在每一显示周期的阈值补偿阶段：发光控制模块13控制V1写入驱动晶体管DTFT的漏极，控制驱动晶体管DTFT的源极与发光元件LE连接；接通控制模块11控制所述驱动晶体管DTFT的栅极和驱动晶体管DTFT的漏极连接，即驱动晶体管DTFT为二极管连接，驱动晶体管DTFT进入饱和状态，驱动晶体管DTFT的栅源电压为阈值电压Vth，此时第一端A电压为V1，第二端B电压为V1-Vth，存储电容C1的第一端A和存储电容C1的第二端B之间的电压差为阈值电压Vth，从而控制驱动晶体管的阈值电压Vth写入存储电容C1；
在每一显示周期的写入阶段：发光控制模块13控制断开驱动晶体管DTFT的漏极与输出第一电源电压V1的第一电源电压线的连接，并控制断开驱动晶体管DTFT的源极与发光元件LE的连接；接通控制模块11持续控制所述驱动晶体管DTFT的栅极和驱动晶体管DTFT的漏极连接，驱动晶体管DTFT保持二极管连接；写入控制模块12控制Vdata写入驱动晶体管DTFT的源极，故第一端A电压为Vdata+Vth，写入控制模块12控制第二端B电压被下拉至参考电压Vref，存储电容C1的第一端A和存储电容C1的第二端B之间的电压差为Vdata+Vth-Vref，驱动晶体管的阈值电压Vth和数据电压Vdata写入存储电容C1，此时参考电压Vref可以清除上一帧与驱动晶体管DTFT的源极连接的发光元件LE的端子的电压；
在每一显示周期的发光保持阶段：发光控制模块13控制驱动晶体管DTFT的漏极接入第一电源电压V1并控制驱动晶体管DTFT的源极分别与发光元件LE和存储电容C1的第二端B连接，接通控制模块11控制断开驱动晶体管DTFT的栅极与驱动晶体管DTFT的漏极之间的连接，写入控制模块12控制存储电容C1的第二端B停止接入参考电压Vref并控制断开驱动晶体管DTFT的源极与Data之间的连接，从而驱动晶体管DTFT的栅源电压Vgs即为存储电容C1的第一端A和存储电容C1的第二端B之间的电压差，由于存储电容C1两端的电压差不能突变，因此此时存储电容C1的第一端A和存储电容C1的第二端B之间的电压差仍为Vdata+Vth-Vref，从而控制驱动晶体管DTFT的驱动电流与驱动晶体管DTFT的阈值电压Vth无关；
并且由于在所述写入阶段参考电压Vref写入驱动晶体管DTFT的源极，从而避免驱动晶体管DTFT的源极电压为发光元件LE的开启电压而导致的在 所述发光保持阶段时驱动晶体管DTFT的栅源电压与LE的开启电压有关的情况，从而使得在所述发光保持阶段驱动晶体管DTFT的驱动电流与发光元件LE的开启电压无关，以使得该驱动电流不受发光元件的老化的影响。
具体地，如果在写入阶段不采用参考电压Vref写入驱动晶体管DTFT的源极，而是存储电容C1的第二端B直接与发光元件LE连接的话，则在写入阶段存储电容C1的第二端B的电压VB为发光元件LE的开启电压Vle，存储电容C1的第一端A和存储电容C1的第二端B之间的电压差即为Vdata+Vth-Vle，由于存储电容C1两端的电压差不能突变，则在发光保持阶段存储电容C1的第一端A和存储电容C1的第二端B之间的电压差维持为Vdata+Vth-Vle，这样的话驱动晶体管驱动发光元件发光的驱动电流就会与发光元件的开启电压有关，所述驱动电流会受到发光元件老化的影响。
具体地，如图2A所示，所述发光元件可以包括有机发光二极管OLED；
所述有机发光二极管OLED，阳极与所述存储电容C1的第二端连接，阴极接入第二电源电压V2；
可选地，在每一显示周期的写入阶段，所述参考电压Vref小于或等于所述第二电源电压V2，从而控制在所述写入阶段有机发光二极管OLED不发光，以延长OLED的寿命。
可选地，所述阈值补偿阶段持续的时间小于预定时间；
由于在所述阈值补偿阶段发光元件是由处于饱和状态的驱动晶体管驱动而发光的，为了减小显示效果的影响，需尽量减少阈值补偿阶段持续的时间。
具体地，如图2B所示，所述接通控制模块包括：接通控制晶体管T1，栅极接入接通控制信号CR，第一极与所述驱动晶体管DTFT的第一极连接，第二极与所述驱动晶体管DTFT的栅极连接；
在图2B中，所述接通控制晶体管T1为n型晶体管。
具体地，如图2C所示，所述写入控制模块包括：数据写入晶体管T2，栅极接入扫描信号Scan，第一极与所述数据线Data连接，第二极与所述驱动晶体管DTFT的第二极连接；以及，
参考电压写入晶体管T3，栅极接入所述扫描信号Scan，第一极与所述存储电容Cs的第二端连接，第二极接入所述参考电压Vref；
在图2C中，所述数据写入晶体管T2和所述参考电压写入晶体管T3都为n型晶体管。
具体地，如图2D所示，所述发光控制模块可以包括：
第一发光控制晶体管T4，栅极接入发光控制信号Em，第一极接入所述第一电源电压V1，第二极与所述驱动晶体管DTFT的第一极连接；以及，
第二发光控制晶体管T5，栅极接入所述发光控制信号Em，第一极与所述驱动晶体管DTFT的第二极连接，第二极与所述有机发光二极管OLED的阳极连接；
在图2D中，所述第一发光控制晶体管T4和所述第二发光控制晶体管T5都为n型晶体管。
具体地，如图2E所示，所述发光控制信号Em为扫描信号Scan；
所述发光控制模块包括：第一发光控制晶体管T4，栅极接入所述扫描信号Scan，第一极与所述驱动晶体管DTFT的第一极连接，第二极接入所述第一电源电压V1；以及，
第二发光控制晶体管T5，栅极接入所述扫描信号Scan，第一极与所述有机发光二极管OLED的阳极连接，第二极与所述驱动晶体管DTFT的第二极连接。
具体地，在图2E中，所述第一发光控制晶体管和所述第二发光控制晶体管都为p型晶体管。
本公开文本所有实施例中采用的晶体管均可以为薄膜晶体管或场效应管或其他特性相同的器件。在本公开文本实施例中，为将晶体管除栅极之外的两极称为第一极和第二极，其中，第一极和第二极可以随着电流流向的改变而互换，也即第一极为源极，第二极为漏极，或者，第一极为漏极，第二极为源极。此外，按照晶体管的特性本公开文本实施例中采用的晶体管可以为n型晶体管或p型晶体管。
下面根据两个具体实施例来说明本公开文本所述的像素驱动电路。
如图3所示，本公开文本一些实施例所述的像素驱动电路包括驱动晶体管DTFT、存储电容C1、接通控制模块、写入控制模块和发光控制模块；
所述存储电容的第一端A与所述驱动晶体管DTFT的栅极连接；
所述接通控制模块包括：接通控制晶体管T1，栅极接入接通控制信号CR，漏极与所述驱动晶体管DTFT的漏极连接，源极与所述驱动晶体管DTFT的栅极连接；
所述写入控制模块包括：数据写入晶体管T2，栅极接入扫描信号Scan，漏极与输出数据电压Vdata的数据线Data连接，源极与所述驱动晶体管DTFT的源极连接；以及，参考电压写入晶体管T3，栅极接入所述扫描信号Scan，第一极与所述存储电容C1的第二端B连接，第二极接入参考电压Vref；
所述发光控制模块包括：第一发光控制晶体管T4，栅极接入发光控制信号Em，第一极接入高电平VDD，第二极与所述驱动晶体管DTFT的漏极连接；以及，
第二发光控制晶体管T5，栅极接入所述发光控制信号Em，第一极与所述驱动晶体管DTFT的源极连接，第二极与有机发光二极管OLED的阳极连接；
所述有机发光二极管OLED的阴极接入低电平VSS；
所述驱动晶体管DTFT、所述接通控制晶体管T1、所述数据写入晶体管T2、所述参考电压写入晶体管T3、所述第一发光控制晶体管T4和所述第二发光控制晶体管T5都为n型晶体管。
如图4所示，本公开文本如图3所示的像素驱动电路在工作时，
在阈值补偿阶段t1，接通控制信号CR和发光控制信号Em都为高电平，扫描信号Scan为低电平，接通控制晶体管T1、第一发光控制晶体管T4和第二发光控制晶体管T5都开启，数据写入晶体管T2和参考电压写入晶体管T3都关闭，如图5A所示，驱动晶体管DTFT为二极管连接，驱动晶体管DTFT进入饱和状态，驱动晶体管DTFT的栅源电压Vgs为驱动晶体管DTFT的阈值电压Vth，第一端A的电压为高电平VDD，第二端B的电压为VDD-Vth，存储电容C1的第一端A和存储电容C1的第二端B之间的电压差为阈值电压Vth，驱动晶体管DTFT的阈值电压Vth写入存储电容C1；
在写入阶段t2，接通控制信号CR和扫描信号Scan都为高电平，发光控制信号Em为低电平，接通控制晶体管T1、数据写入晶体管T2和参考电压写入晶体管T3都开启，第一发光控制晶体管T4和第二发光控制晶体管T5都关闭，如图5B所示，驱动晶体管DTFT保持二极管连接，驱动晶体管DTFT的栅 源电压Vgs为阈值电压Vth，驱动晶体管DTFT的源极接入数据电压Vdata，故第一端A的电压为Vdata+Vth，第二端B的电压被下拉至参考电压Vref，因此存储电容C1的第一端A和存储电容C1的第二端B之间的电压差为Vdata+Vth-Vref，驱动晶体管DTFT的阈值电压Vth和数据电压Vdata写入存储电容C1，此时参考电压Vref可以清除上一帧OLED的阳极电压；
在发光保持阶段t3，接通控制信号CR和扫描信号Scan都为低电平，发光控制信号Em为高电平，接通控制晶体管T1、参考电压写入晶体管T3和参考电压写入晶体管T3都关闭，第一发光控制晶体管T4和第二发光控制晶体管T5都开启，如图5C所示，存储电容C1的第一端A的电压驱动驱动晶体管DTFT，使OLED开始发光，存储电容C1的第二端B的电压VB为OLED的开启电压Voled，由于存储电容C1两端的电压差不能突变，因此存储电容C1的第一端A的电压VA＝Vdata+Vth-Vref+Voled；
驱动晶体管DTFT的栅源电压Vgs＝VA-VB＝Vdata+Vth-Vref；
则流过OLED的电流(即驱动晶体管DTFT的驱动电流)I如下：
I＝K×(Vgs-Vth)2＝K×(Vdata-Vref)2；
OLED保持发光状态，并在发光保持阶段t3流过OLED的电流与阈值电压Vth无关，这样就可以改善电流的均匀性，从而达到显示亮度的均匀。
并且，如果如图3所示的本公开文本所述的像素驱动电路不包括参考电压写入晶体管T3，即在写入阶段t2不控制参考电压Vref写入存储电容C1的第二端B，则存储电容C1的第二端的电压则为OLED的开启电压Voled，这样的话在发光保持阶段t3驱动晶体管DTFT的栅源电压就会与OLED的开启电压Voled有关系，由于随着OLED的老化开启电压Voled会改变，这样流过OLED的电流则会受到OLED的老化的影响，而本公开文本实施例所述的像素驱动电流由于采用了写入控制模块在写入阶段控制参考电压Vref写入存储电容C1的第二端(在图3中采用了参考电压写入晶体管T3)，则可以避免以上情况的发生。
具体地，如果在写入阶段t2不采用参考电压Vref写入驱动晶体管DTFT的源极，而是存储电容C1的第二端B直接与OLED的阳极连接的话，则在写入阶段存储电容C1的第二端B的电压VB为OLED的开启电压Voled，存储电 容C1的第一端A和存储电容C1的第二端B之间的电压差即为Vdata+Vth-Voled，由于存储电容C1两端的电压差不能突变，则在发光保持阶段存储电容C1的第一端A和存储电容C1的第二端B之间的电压差维持为Vdata+Vth-Voled，这样的话驱动晶体管驱动OLED发光的驱动电流就会与OLED的开启电压Voled有关，所述驱动电流会受到OLED老化的影响。
如图6所示，本公开文本所述的另一个像素驱动电路包括驱动晶体管DTFT、存储电容C1、接通控制模块、写入控制模块和发光控制模块；
所述存储电容的第一端A与所述驱动晶体管DTFT的栅极连接；
所述接通控制模块包括：接通控制晶体管T1，栅极接入接通控制信号CR，漏极与所述驱动晶体管DTFT的漏极连接，源极与所述驱动晶体管DTFT的栅极连接；
所述写入控制模块包括：
数据写入晶体管T2，栅极接入扫描信号Scan，漏极与输出数据电压Vdata的数据线Data连接，源极与所述驱动晶体管DTFT的源极连接；以及，
参考电压写入晶体管T3，栅极接入所述扫描信号Scan，第一极与所述存储电容C1的第二端B连接，第二极接入参考电压Vref；
所述发光控制模块包括：
第一发光控制晶体管T4，栅极接入所述扫描信号Scan，源极与所述驱动晶体管DTFT的漏极连接，漏极接入高电平VDD；以及，
第二发光控制晶体管T5，栅极接入所述扫描信号Scan，源极与有机发光二极管OLED的阳极连接，漏极与所述驱动晶体管DTFT的源极连接；
所述驱动晶体管DTFT、所述接通控制晶体管T1、所述数据写入晶体管T2和所述参考电压写入晶体管T3都为n型晶体管，所述第一发光控制晶体管T4和所述第二发光控制晶体管T5都为p型晶体管。
如图7所示，本公开文本如图6所示的像素驱动电路在工作时，
在阈值补偿阶段t1，接通控制信号CR为高电平，扫描信号Scan为低电平，接通控制晶体管T1、第一发光控制晶体管T4和第二发光控制晶体管T5都开启，数据写入晶体管T2和参考电压写入晶体管T3都关闭，驱动晶体管DTFT为二极管连接，驱动晶体管DTFT进入饱和状态，驱动晶体管DTFT的栅 源电压Vgs为驱动晶体管DTFT的阈值电压Vth，第一端A的电压为高电平VDD，第二端B的电压为VDD-Vth，存储电容C1的第一端A和存储电容C1的第二端B之间的电压差为阈值电压Vth，驱动晶体管DTFT的阈值电压Vth写入存储电容C1；
在写入阶段t2，接通控制信号CR和扫描信号Scan都为高电平，接通控制晶体管T1、数据写入晶体管T2和参考电压写入晶体管T3都开启，第一发光控制晶体管T4和第二发光控制晶体管T5都关闭，如图5B所示，驱动晶体管DTFT保持二极管连接，驱动晶体管DTFT的栅源电压Vgs为阈值电压Vth，驱动晶体管DTFT的源极接入数据电压Vdata，故第一端A的电压为Vdata+Vth，第二端B电压被下拉至参考电压Vref，因此存储电容C1的第一端A和存储电容C1的第二端B之间的电压差为Vdata+Vth-Vref，驱动晶体管DTFT的阈值电压Vth和数据电压Vdata写入存储电容C1，此时参考电压Vref可以清除上一帧OLED的阳极电压；
在发光保持阶段t3，接通控制信号CR和扫描信号Scan都为低电平，接通控制晶体管T1、参考电压写入晶体管T3和参考电压写入晶体管T3都关闭，第一发光控制晶体管T4和第二发光控制晶体管T5都开启，如图5C所示，存储电容C1的第一端A的电压驱动驱动晶体管DTFT，使OLED开始发光，存储电容C1的第二端B的电压VB为OLED的开启电压Voled，由于存储电容C1两端的电压差不能突变，因此存储电容C1的第一端A的电压VA＝Vdata+Vth-Vref+Voled；
驱动晶体管DTFT的栅源电压Vgs＝VA-VB＝Vdata+Vth-Vref；
则流过OLED的电流(即驱动晶体管DTFT的驱动电流)I如下：
I＝K×(Vgs-Vth)2＝K×(Vdata-Vref)2；
OLED保持发光状态，并在发光保持阶段t3流过OLED的电流与阈值电压Vth无关，这样就可以改善电流的均匀性，从而达到显示亮度的均匀。
并且，如果如图6所示的像素驱动电路不包括参考电压写入晶体管T3，即在写入阶段t2不控制参考电压Vref写入存储电容C1的第二端B，则存储电容C1的第二端的电压为OLED的开启电压Voled，这样的话在发光保持阶段t3驱动晶体管DTFT的栅源电压就会与OLED的开启电压Voled有关系，由 于随着OLED的老化Voled会改变，这样流过OLED的电流就会受到OLED的老化的影响，而本公开文本实施例所述的像素驱动电流由于采用了写入控制模块在写入阶段控制参考电压Vref写入存储电容C1的第二端(在图6中采用了参考电压写入晶体管T3)，则可以避免以上情况的发生。
本公开文本实施例所述的像素驱动方法，应用于上述的像素驱动电路，所述像素驱动方法包括：
阈值补偿步骤：在每一显示周期的阈值补偿阶段，接通控制信号和发光控制信号都为有效信号(所述有效信号即控制相应的模块导通的信号)，接通控制模块和发光控制模块导通，控制所述驱动晶体管为二极管连接，以通过存储电容的第一端和存储电容的第二端之间的电压差补偿所述驱动晶体管的阈值电压Vth；
写入步骤：在每一显示周期的写入阶段，接通控制信号和扫描信号都为有效信号，接通控制模块和写入控制模块导通，控制所述驱动晶体管保持为二极管连接，将数据线上的数据电压Vdata通过驱动晶体管写入所述存储电容的第一端，将参考电压Vref写入所述存储电容的第二端；
发光步骤：在每一显示周期的发光保持阶段，发光控制信号为有效信号，发光控制模块导通，通过所述存储电容中存储的电荷控制驱动晶体管导通以驱动发光元件发光。
本公开文本实施例所述的像素驱动方法通过接通控制模块和写入控制模块将驱动晶体管的阈值电压Vth和数据线上的数据电压Vdata分步写入至存储电容，从而使得驱动晶体管的栅源电压包含Vdata+Vth，从而控制发光保持阶段时驱动晶体管的驱动电流与驱动晶体管的阈值电压Vth无关，达到显示均匀的目的。本公开文本实施例所述的像素驱动电路还通过写入控制模块在写入阶段将参考电压写入存储电容的第二端，从而可以控制发光保持阶段时驱动晶体管的驱动电流与发光元件的开启电压无关，以使得发光保持阶段时驱动晶体管的驱动电流不受发光元件的老化的影响。
可选地，所述阈值补偿阶段持续的时间小于预定时间；
由于在所述阈值补偿阶段发光元件是由处于饱和状态的驱动晶体管驱动而发光的，为了减小显示效果的影响，需尽量减少阈值补偿阶段持续的时间。
本公开文本实施例所述的显示面板包括上述的像素驱动电路。
本公开文本实施例所述的显示装置包括上述的显示面板。
所述显示装置例如可以为：电子纸、OLED显示装置、手机、平板电脑、电视机、显示器、笔记本电脑、数码向框、导航仪等任何具有显示功能的产品或部件
以上所述是本公开文本的可选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本公开文本所述原理的前提下，还可以作出若干改进和润饰，这些改进和润饰也应视为本公开文本的保护范围。

Claims (13)

  1. 一种像素驱动电路，包括驱动晶体管、存储电容、接通控制模块、写入控制模块和发光控制模块，其中，
    所述驱动晶体管的栅极通过所述接通控制模块与所述驱动晶体管的第一极连接，所述驱动晶体管的第一极通过所述发光控制模块接入第一电源电压，所述驱动晶体管的第二极通过所述发光控制模块与发光元件连接并通过所述写入控制模块与数据线连接；
    所述存储电容的第一端与所述驱动晶体管的栅极连接，所述存储电容的第二端通过所述发光控制模块与所述驱动晶体管的第二极连接并通过所述写入控制模块接入参考电压；
    所述接通控制模块接入接通控制信号，用于在每一显示周期的阈值补偿阶段和写入阶段，在所述接通控制信号的控制下控制所述驱动晶体管的栅极和所述驱动晶体管的第一极连接，以使得所述驱动晶体管为二极管连接，从而控制所述驱动晶体管的阈值电压写入所述存储电容；
    所述写入控制模块接入扫描信号，用于在每一显示周期的写入阶段在所述扫描信号的控制下控制所述数据线上的数据电压写入所述驱动晶体管的第二极，控制所述参考电压写入所述存储电容的第二端；以及
    所述发光控制模块接入发光控制信号，用于在每一显示周期的阈值补偿阶段和发光保持阶段在所述发光控制信号的控制下控制所述驱动晶体管的第一极接入所述第一电源电压，控制所述驱动晶体管的第二极与所述发光元件连接。
  2. 如权利要求1所述的像素驱动电路，其中，所述发光元件包括有机发光二极管，所述有机发光二极管的阳极与所述存储电容的第二端连接，所述有机发光二极管的阴极接入第二电源电压；
    在每一显示周期的写入阶段，所述参考电压小于或等于所述第二电源电压。
  3. 如权利要求1或2所述的像素驱动电路，其中，所述接通控制模块包括：接通控制晶体管，所述接通控制晶体管的栅极接入接通控制信号，所述 接通控制晶体管的第一极与所述驱动晶体管的第一极连接，所述接通控制晶体管的第二极与所述驱动晶体管的栅极连接。
  4. 如权利要求3所述的像素驱动电路，其中，所述写入控制模块包括：
    数据写入晶体管，所述数据写入晶体管的栅极接入扫描信号，所述数据写入晶体管的第一极与所述数据线连接，所述数据写入晶体管的第二极与所述驱动晶体管的第二极连接；以及，
    参考电压写入晶体管，所述参考电压写入晶体管的栅极接入所述扫描信号，所述参考电压写入晶体管的第一极与所述存储电容的第二端连接，所述参考电压写入晶体管的第二极接入所述参考电压。
  5. 如权利要求4所述的像素驱动电路，其中，所述发光控制模块包括：
    第一发光控制晶体管，所述第一发光控制晶体管的栅极接入发光控制信号，所述第一发光控制晶体管的第一极接入所述第一电源电压，所述第一发光控制晶体管的第二极与所述驱动晶体管的第一极连接；以及，
    第二发光控制晶体管，所述第二发光控制晶体管的栅极接入所述发光控制信号，所述第二发光控制晶体管的第一极与所述驱动晶体管的第二极连接，所述第二发光控制晶体管的第二极与所述发光元件连接。
  6. 如权利要求5所述的像素驱动电路，其中，所述驱动晶体管、所述接通控制晶体管、所述数据写入晶体管、所述参考电压写入晶体管、所述第一发光控制晶体管和所述第二发光控制晶体管都为n型晶体管。
  7. 如权利要求4所述的像素驱动电路，其中，所述发光控制信号为所述扫描信号，
    所述发光控制模块包括：第一发光控制晶体管，所述第一发光控制晶体管的栅极接入所述扫描信号，所述第一发光控制晶体管的第一极与所述驱动晶体管的第一极连接，所述第一发光控制晶体管的第二极接入所述第一电源电压；以及，第二发光控制晶体管，所述第二发光控制晶体管的栅极接入所述扫描信号，所述第二发光控制晶体管的第一极与所述发光元件连接，所述第二发光控制晶体管的第二极与所述驱动晶体管的第二极连接。
  8. 如权利要求7所述的像素驱动电路，其中，所述驱动晶体管、所述接通控制晶体管、所述数据写入晶体管和所述参考电压写入晶体管都为n型晶 体管，所述第一发光控制晶体管和所述第二发光控制晶体管都为p型晶体管。
  9. 如权利要求7所述的像素驱动电路，其中，所述接通控制晶体管、所述数据写入晶体管和所述参考电压写入晶体管都为n型晶体管，所述驱动晶体管、所述第一发光控制晶体管和所述第二发光控制晶体管都为p型晶体管
  10. 一种应用于如权利要求1至9中任一权利要求所述的像素驱动电路的像素驱动方法，包括：
    阈值补偿步骤：在每一显示周期的阈值补偿阶段，接通控制信号和发光控制信号都为有效信号，接通控制模块和发光控制模块导通，控制所述驱动晶体管为二极管连接，以通过存储电容的第一端和存储电容的第二端之间的电压差补偿所述驱动晶体管的阈值电压Vth；
    写入步骤：在每一显示周期的写入阶段，接通控制信号和扫描信号都为有效信号，接通控制模块和写入控制模块导通，控制所述驱动晶体管保持为二极管连接，将数据线上的数据电压Vdata通过驱动晶体管写入所述存储电容的第一端，将参考电压Vref写入所述存储电容的第二端；以及
    发光步骤：在每一显示周期的发光保持阶段，发光控制信号为有效信号，发光控制模块导通，通过所述存储电容中存储的电荷控制驱动晶体管导通以驱动发光元件发光。
  11. 如权利要求10所述的像素驱动方法，其中，所述阈值补偿阶段持续的时间小于预定时间。
  12. 一种显示面板，包括如权利要求1至9中任一权利要求所述的像素驱动电路。
  13. 一种显示装置，包括如权利要求12所述的显示面板。
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