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WO2013127189A1 - Circuit d'entraînement d'unité de pixel, procédé d'entraînement d'unité de pixel et unité de pixel - Google Patents

Circuit d'entraînement d'unité de pixel, procédé d'entraînement d'unité de pixel et unité de pixel Download PDF

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Publication number
WO2013127189A1
WO2013127189A1 PCT/CN2012/084015 CN2012084015W WO2013127189A1 WO 2013127189 A1 WO2013127189 A1 WO 2013127189A1 CN 2012084015 W CN2012084015 W CN 2012084015W WO 2013127189 A1 WO2013127189 A1 WO 2013127189A1
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WO
WIPO (PCT)
Prior art keywords
thin film
film transistor
driving
oled
source
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.)
Ceased
Application number
PCT/CN2012/084015
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English (en)
Chinese (zh)
Inventor
青海刚
祁小敬
高永益
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BOE Technology Group Co Ltd
Chengdu BOE Optoelectronics Technology Co Ltd
Original Assignee
BOE Technology Group Co Ltd
Chengdu BOE Optoelectronics Technology Co Ltd
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Publication of WO2013127189A1 publication Critical patent/WO2013127189A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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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
    • G09G3/22—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
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0819—Several active elements per pixel in active matrix panels used for counteracting undesired variations, e.g. feedback or autozeroing
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0842—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0842—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor
    • 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

Definitions

  • Pixel unit driving circuit Pixel unit driving method, and pixel unit
  • the present invention relates to the field of organic light emitting display, and more particularly to a pixel unit driving circuit, a pixel unit driving method, and a pixel unit. Background technique
  • the AMOLED Active Matrix Organic Light Emitting Diode
  • the AMOLED is capable of emitting light by a current generated when a driving TFT (Thin Film Transistor) is saturated, because different widths are input when the same gray scale voltage is input.
  • the value voltage produces different drive currents, causing current inconsistencies.
  • Vth crystal tube threshold voltage
  • Vth also drifts, so the brightness uniformity of the conventional 2T1C circuit has been poor.
  • the conventional 2T1C pixel unit driving circuit is shown in Figure 1.
  • the circuit contains only two TFTs, T1 is used as a switch, and DTFT is used for pixel driving.
  • the conventional 2T1C pixel unit driving circuit is also relatively simple to operate.
  • the control timing diagram of the 2T1C pixel unit driving circuit is as shown in FIG. 2. When the scanning level Vscan of the scanning line Scan output is low, T1 is turned on, and the data line Data is The upper gray scale voltage charges the capacitor C. When the scan level is high, T1 is turned off, and the capacitor C is used to store the gray scale voltage.
  • the driving current formula of the 2T1C pixel unit driving circuit includes Vth.
  • the Vth of the TFTs at different positions of the manufactured panel is greatly different, resulting in a large difference.
  • the driving current of the OLED is different under the same gray scale voltage, so the brightness of the panel at different positions of the driving scheme may be different, and the brightness uniformity is poor.
  • the OLED material gradually ages, resulting in an increase in the threshold voltage of the OLED, and at the same current, the luminous efficiency of the OLED material decreases, and the brightness of the panel decreases.
  • a main object of the present invention is to provide a pixel unit driving circuit and a pixel unit driving method And the pixel unit can compensate the threshold voltage of the driving thin film transistor while compensating for the driving current drop caused by the rising aging threshold voltage of the OLED material.
  • the present invention provides a pixel unit driving circuit for driving an OLED, including a driving thin film transistor, a first switching element, a storage capacitor, a driving control unit, and a charging control unit, wherein
  • a gate of the driving thin film transistor is connected to the first end of the storage capacitor, and is further connected to a drain of the driving thin film transistor through the charging control unit;
  • a source of the driving thin film transistor is connected to the first end of the OLED, and is connected to the second end of the storage capacitor through the driving control unit;
  • the drain of the driving thin film transistor is connected to the first end of the driving power source through the first switching element;
  • the second end of the storage capacitor Cs is further connected to the first end of the driving power source through the charging control unit;
  • the second end of the OLED is connected to the second end of the driving power source through the driving control unit;
  • the second end of the OLED is connected to the data line through the charging control unit.
  • the driving thin film transistor is a p-type thin film transistor
  • the first end of the OLED is a cathode of the OLED, and the second end of the OLED is the
  • An anode of the OLED, and a source of the driving thin film transistor is connected to a cathode of the OLED; a first end of the driving power source is a low level output end of the driving power source, and a second end of the driving power source is a high level output terminal of the driving power source, and a drain of the driving thin film transistor is connected to a low level output end of the driving power source through the first switching element;
  • the second end of the storage capacitor is connected to the low level output terminal of the driving power source through the charging control unit.
  • the first switching element is a first thin film transistor
  • the driving control unit includes a second thin film transistor and a third thin film transistor
  • the charging control unit includes a fourth thin film transistor, a fifth thin film transistor, and a Six thin film transistors
  • the first thin film transistor has a gate connected to the first control line, a drain connected to the low level output end of the driving power source, and a source connected to the drain of the driving thin film transistor;
  • the second thin film transistor has a gate connected to the second control line, a source and the driving power source a high level output is connected, and a drain is connected to an anode of the OLED;
  • the third thin film transistor has a gate connected to the second control line, a source connected to the source of the driving thin film transistor, and a drain connected to the second end of the storage capacitor;
  • the fourth thin film transistor has a gate connected to the first control line, a drain connected to the first end of the storage capacitor, and a source connected to the drain of the driving thin film transistor;
  • the fifth thin film transistor has a gate connected to the first control line, a source connected to the low level output end of the driving power source, and a drain connected to the second end of the storage capacitor;
  • the sixth thin film transistor has a gate connected to the first control line, a source connected to the anode of the OLED, and a drain connected to the data line;
  • the first thin film transistor, the second thin film transistor, and the third thin film transistor are all p-type thin film transistors, and the fourth switching element, the fifth thin film transistor, and the sixth thin film transistor are n-type Thin film transistor.
  • the first switching element is a first thin film transistor
  • the driving control unit includes a second thin film transistor and a third thin film transistor
  • the charging control unit includes a fourth thin film transistor, a fifth thin film transistor, and a sixth thin film transistor
  • the first thin film transistor has a gate connected to the first control line, a drain connected to the low level output end of the driving power source, and a source connected to the drain of the driving thin film transistor;
  • the second thin film transistor has a gate connected to the second control line, a source connected to the high level output end of the driving power source, and a drain connected to the anode of the OLED;
  • the third thin film transistor has a gate connected to the second control line, a source connected to the source of the driving thin film transistor, and a drain connected to the second end of the storage capacitor;
  • the fourth thin film transistor has a gate connected to the first control line, a drain connected to the first end of the storage capacitor, and a source connected to the drain of the driving thin film transistor;
  • the fifth thin film transistor has a gate connected to the first control line, a source connected to the second end of the storage capacitor, and a drain connected to the high level output end of the driving power source;
  • the sixth thin film transistor has a gate connected to the first control line, a source connected to the anode of the OLED, and a drain connected to the data line;
  • the first thin film transistor, the second thin film transistor, and the third thin film transistor are all p-type thin film transistors, and the fourth switching element, the fifth thin film transistor, and the sixth thin film transistor are n-type Thin film transistor.
  • the driving thin film transistor is an n-type thin film transistor; a first end of the OLED is an anode of the OLED, a second end of the OLED is a cathode of the OLED, and the driving a source of the thin film transistor is connected to an anode of the OLED; a first end of the driving power source is a high level output end of the driving power source, and a second end of the driving power source is a low level of the driving power source An output end, and a drain of the driving thin film transistor is connected to a high level output end of the driving power source through the first switching element;
  • the second end of the storage capacitor is connected to the high-level output terminal of the driving power source through the charging control unit.
  • the first switching element is a first thin film transistor
  • the charging control unit includes a second thin film transistor, a third thin film transistor, and a fourth thin film transistor
  • the driving control unit includes a fifth thin film transistor and a Six thin film transistors
  • the first thin film transistor has a gate connected to the first control line, a drain connected to a drain of the driving thin film transistor, and a source connected to a high level output end of the driving power source;
  • the second thin film transistor has a gate connected to the first control line, a source connected to the second end of the storage capacitor, and a drain connected to the high level output end of the driving power source;
  • the third thin film transistor has a gate connected to the first control line, a drain connected to a drain of the driving thin film transistor, and a source connected to a gate of the driving thin film transistor;
  • the fourth thin film transistor has a gate connected to the first control line, a source connected to the data line, and a drain connected to the cathode of the OLED;
  • the fifth thin film transistor has a gate connected to the second control line, a source connected to the second end of the storage capacitor, and a drain connected to the source of the driving thin film transistor;
  • the sixth thin film transistor has a gate connected to the second control line, a source connected to the cathode of the OLED, and a drain connected to the low level output end of the driving power source;
  • the second thin film transistor, the third thin film transistor, and the fourth thin film transistor are n-type thin film transistors, and the first thin film transistor, the fifth thin film transistor, and the sixth thin film transistor are p-type thin film transistors.
  • the first switching element is a first thin film transistor
  • the charging control unit includes a second thin film transistor, a third thin film transistor, and a fourth thin film transistor
  • the driving control unit includes a fifth thin film transistor and a sixth thin film transistor
  • the first thin film transistor has a gate connected to the first control line, and a drain and the driving thin film crystal a drain connection of the body tube, the source being connected to a high level output terminal of the driving power source;
  • the second thin film transistor has a gate connected to the first control line, a source connected to the low level output end of the driving power source, and a drain connected to the second end of the storage capacitor;
  • the third thin film transistor has a gate connected to the first control line, a drain connected to a drain of the driving thin film transistor, and a source connected to a gate of the driving thin film transistor;
  • the fourth thin film transistor has a gate connected to the first control line, a source connected to the data line, and a drain connected to the cathode of the OLED;
  • the fifth thin film transistor has a gate connected to the second control line, a source connected to the second end of the storage capacitor, and a drain connected to the source of the driving thin film transistor;
  • the sixth thin film transistor has a gate connected to the second control line, a source connected to the cathode of the OLED, and a drain connected to the low level output end of the driving power source;
  • the second thin film transistor, the third thin film transistor, and the fourth thin film transistor are n-type thin film transistors, and the first thin film transistor, the fifth thin film transistor, and the sixth thin film transistor are p-type thin film transistors.
  • the present invention also provides a pixel unit driving method, which is applied to the above pixel unit driving circuit, and the pixel unit driving method includes the following steps:
  • Pixel charging step the charging control unit first controls the driving of the driving thin film transistor, and controls charging of the storage capacitor until the gate potential of the driving thin film transistor rises to cause the driving thin film transistor to be turned off;
  • Driving the OLED light emitting display step the driving control unit controls the driving thin film transistor to be turned on and the gate thereof is in a floating state to drive the OLED light emitting display and make the gate-source voltage of the driving thin film transistor compensate the threshold value of the driving thin film transistor Voltage.
  • the present invention also provides a pixel unit including an OLED and a pixel unit driving circuit according to the above embodiment;
  • the pixel unit driving circuit includes a source of a driving thin film transistor connected to a cathode of the OLED, and an anode of the OLED is connected to a high level output end of the driving power source through the driving control unit, where the driving thin film transistor is The drain is connected to the low level output of the driving power source through the first switching element.
  • the present invention also provides a pixel unit including an OLED and a pixel unit driving circuit according to another embodiment described above; a source of the driving thin film transistor included in the pixel unit driving circuit is connected to an anode of the OLED, and a cathode of the OLED is connected to a low level output end of the driving power source through the driving control unit, where the driving thin film transistor The drain is connected to the high level output terminal of the driving power source through the first switching unit.
  • the pixel unit driving circuit, the pixel unit driving method and the pixel unit of the present invention are input from the source of the DTFT through the data voltage Vdata, and the self-discharge of the DTFT is used to connect the Vth (the threshold of the DTFT) Voltage), Vdata (data voltage), Vth-oled (the threshold voltage of OLED light) is stored in the storage capacitor Cs, compensating for the threshold voltage of the driving thin film transistor, and using the voltage feedback mechanism to compensate for the wide value caused by aging of the OLED material The drive current caused by the voltage rise drops.
  • Vth the threshold of the DTFT
  • Vdata data voltage
  • Vth-oled the threshold voltage of OLED light
  • 1 is a circuit diagram of a conventional 2T1C pixel unit driving circuit
  • 2 is a control timing chart of the conventional 2T1C pixel unit driving circuit
  • FIG. 3 is a circuit diagram of a pixel unit driving circuit according to a first embodiment of the present invention.
  • FIG. 4 is a circuit diagram of a pixel unit driving circuit according to a second embodiment of the present invention.
  • FIG. 5 is a circuit diagram of a pixel unit driving circuit according to a third embodiment of the present invention.
  • FIG. 6 is a circuit diagram of a pixel unit driving circuit according to a fourth embodiment of the present invention.
  • FIG. 7 is a circuit diagram of a pixel unit driving circuit according to a fifth embodiment of the present invention.
  • FIG. 8 is a circuit diagram of a pixel unit driving circuit according to a sixth embodiment of the present invention.
  • FIG. 9 is a timing chart of signals when a pixel unit driving circuit according to a second embodiment of the present invention operates.
  • FIG. 10A is an equivalent circuit diagram of a pixel unit driving circuit according to a second embodiment of the present invention in a first period of time
  • FIG. 10B is an equivalent circuit diagram of the pixel unit driving circuit in the second period of time according to the second embodiment of the present invention.
  • FIG. 10C is an equivalent circuit diagram of the pixel unit driving circuit in the third period of time according to the second embodiment of the present invention.
  • 11A is an equivalent circuit diagram of a pixel unit driving circuit according to a third embodiment of the present invention in a first period of time
  • 11B is an equivalent circuit diagram of a pixel unit driving circuit according to a third embodiment of the present invention in a second period of time
  • 11C is an equivalent circuit diagram of the pixel unit driving circuit in the third period of time according to the third embodiment of the present invention.
  • Fig. 12 is a timing chart showing signals of the pixel unit driving circuit according to the fifth embodiment of the present invention and the pixel unit driving circuit of the sixth embodiment. detailed description
  • the pixel unit driving circuit is configured to drive an OLED, including a driving thin film transistor DTFT, a first switching element 10, a storage capacitor Cs, a driving control unit 11, and a charging control unit 12. , among them,
  • the gate of the driving thin film transistor DTFT is connected to the first end of the storage capacitor Cs, and is also connected to the drain of the driving thin film transistor DTFT through the charging control unit 12;
  • the source of the driving thin film transistor DTFT is connected to the cathode of the OLED, and is connected to the second end of the storage capacitor Cs through the driving control unit 11;
  • the drain of the driving thin film transistor DTFT is connected to the low-level output terminal of the driving power source through the first switching element 10;
  • the second end of the storage capacitor Cs is connected to the low-level output end of the driving power source through the charging control unit 12;
  • the anode of the OLED is connected to the high-level output end of the driving power source through the driving control unit 11, and is also connected to the data line through the charging control unit 12;
  • the driving thin film transistor DTFT is a p-type thin film transistor
  • the data line outputs a data voltage Vdata
  • the output voltage of the high-level output terminal of the driving power source is VDD, and the output voltage of the low-level output terminal of the driving power source is VSS;
  • Point P is a node connected to the second end of the storage capacitor Cs
  • point G is the storage capacitor The node to which the first end of the Cs is connected.
  • the charging control unit 12 turns on the connection between the gate and the drain of the DTFT, and turns on the connection between the second end of the Cs and the low-level output of the driving power source. And conducting a connection between the anode of the OLED and the data line; if the previous stage of the driving transistor DTFT is in an off state, the G point (ie, the node connected to the gate of the DTFT) is in a floating state, and the charging control unit The conduction of 12 will cause the floating G point potential to be seriously pulled down, so that the DTFT is turned on.
  • the DTFT If the DTFT is turned on in the previous stage, it will enter the working state of this stage, the DTFT is in the diode connection state, and the data line passes through the OLED.
  • the first switching element 10 turns on a connection between a drain of the DTFT and a low-level output of the driving power source
  • the driving control unit 11 turns on the source of the DTFT and the second of the Cs.
  • the operating voltage is inconsistent with Vth-oled, and the gate of DTFT is floating, so the voltage of Vg jumps to Vdata-Vth-oled- I Vth
  • -VSS +VDD- Voled ) VSS+Vth_oled+ I Vth
  • the current I flowing through the DTFT has nothing to do with the threshold voltage Vth of the DTFT, so that the uniformity of the current can be improved to achieve uniform brightness; while the current I flowing through the DTFT includes Vth-oled.
  • Vth-oled As the use time prolongs, the aging efficiency of the OLED material decreases, Vth-oled rises, and the rise of Vth-oled increases the operating current accordingly, thus improving the panel brightness reduction caused by material aging.
  • the pixel unit driving circuit according to the second embodiment of the present invention is based on the pixel unit driving circuit according to the first embodiment of the present invention;
  • the first switching element 10 is a first thin film transistor T1
  • the driving control unit 11 includes a second thin film transistor T2 and a third thin film transistor T3
  • the charging control unit 12 includes a fourth thin film transistor T4 and a fifth thin film transistor. ⁇ 5 and sixth thin film transistor ⁇ 6;
  • the first thin film transistor T1 has a gate connected to a first control line outputting the first control signal S1, a drain connected to a low level output end of the driving power source, and a drain of the source and the driving thin film transistor DTFT Pole connection
  • the second thin film transistor T2 has a gate connected to a second control line outputting the second control signal S2, a source connected to the high level output end of the driving power source, and a drain connected to the anode of the OLED;
  • the third thin film transistor T3 has a gate connected to the second control line, a source connected to the source of the driving thin film transistor DTFT, and a drain connected to the second end of the storage capacitor Cs;
  • the fourth thin film transistor T4 has a gate connected to the first control line, a drain connected to the first end of the storage capacitor Cs, and a source connected to the drain of the driving thin film transistor DTFT;
  • the fifth thin film transistor T5 has a gate connected to the first control line, a source connected to the low level output end of the driving power source, and a drain connected to the second end of the storage capacitor Cs;
  • the sixth thin film transistor T6 has a gate connected to the first control line, a source connected to the anode of the OLED, and a drain connected to the data line;
  • the first thin film transistor T1, the second thin film transistor T2, and the third thin film transistor T3 are all p-type thin film transistors, and the fourth switching element T4 and the fifth thin film transistor T5 And the sixth thin film transistor T6 is an n-type thin film transistor;
  • the output voltage of the high-level output terminal of the driving power source is VDD, and the output voltage of the low-level output terminal of the driving power source is VSS;
  • Point P is a node connected to the second end of the storage capacitor Cs
  • point G is a node connected to the first end of the storage capacitor Cs.
  • the pixel unit driving circuit according to the third embodiment of the present invention is based on the pixel unit driving circuit according to the first embodiment of the present invention.
  • the first switching element 10 is a first thin film transistor T1
  • the driving control unit 11 includes a second thin film transistor T2 and a third thin film transistor T3
  • the charging control unit 12 includes a fourth thin film transistor T4 and a fifth thin film transistor.
  • the first thin film transistor T1 has a gate connected to a first control line outputting the first control signal S1, a drain connected to a low level output end of the driving power source, a source and the driving thin film transistor
  • the second thin film transistor ⁇ 2 has a gate connected to a second control line outputting the second control signal S2, a source connected to the high level output end of the driving power source, and a drain connected to the anode of the OLED;
  • the third thin film transistor ⁇ 3 has a gate connected to the second control line, a source connected to the source of the driving thin film transistor DTFT, and a drain connected to the second end of the storage capacitor Cs;
  • the fourth thin film transistor T4 has a gate connected to the first control line, a drain connected to the first end of the storage capacitor Cs, and a source connected to the drain of the driving thin film transistor DTFT;
  • the fifth thin film transistor T5 has a gate connected to the first control line, a source connected to the second end of the storage capacitor Cs, and a drain connected to the high-level output end of the driving power source;
  • the sixth thin film transistor T6 has a gate connected to the first control line, a source connected to the anode of the OLED, and a drain connected to the data line;
  • the first thin film transistor T1, the second thin film transistor T2, and the third thin film transistor T3 are all p-type thin film transistors, the fourth switching element T4, the fifth thin film transistor T5, and the sixth
  • the thin film transistor ⁇ 6 is an n-type thin film transistor
  • the output voltage of the high-level output terminal of the driving power source is VDD, and the output voltage of the low-level output terminal of the driving power source is VSS;
  • the defect is a node connected to the second end of the storage capacitor Cs, and the G point is the storage capacitor The node to which the first end of the Cs is connected.
  • the pixel unit driving circuit is configured to drive an OLED, including a driving thin film transistor DTFT, a first switching element 20, a storage capacitor Cs, a driving control unit 21, and a charging control unit 22. , among them,
  • the gate of the driving thin film transistor DTFT is connected to the first end of the storage capacitor Cs, and is also connected to the drain of the driving thin film transistor DTFT through the charging control unit 22;
  • the source of the driving thin film transistor DTFT is connected to the anode of the OLED, and is connected to the second end of the storage capacitor Cs through the driving control unit 21;
  • the drain of the driving thin film transistor DTFT is connected to the high-level output terminal of the driving power source through the first switching element 20;
  • the second end of the storage capacitor Cs is connected to the high-level output end of the driving power source through the charging control unit 22;
  • the cathode of the OLED is connected to the data line through the charging control unit 22, and is also connected to the low-level output end of the driving power source through the driving control unit 21;
  • the driving thin film transistor DTFT is an n-type thin film transistor
  • the data line outputs a data voltage Vdata
  • the output voltage of the high level output terminal of the driving power source is VDD, and the output voltage of the low level output terminal of the driving power source is VSS.
  • a pixel unit driving circuit according to a fifth embodiment of the present invention is based on a pixel unit driving circuit according to a fourth embodiment of the present invention.
  • the first switching element 20 is a first thin film transistor T1
  • the charging control unit 22 includes a second thin film transistor T2, a third thin film transistor T3, and a fourth thin film transistor T4, and the driving control unit 21 includes a fifth thin film transistor.
  • the first thin film transistor T1 has a gate connected to the first control line, a drain connected to the drain of the driving thin film transistor DTFT, and a source connected to the high level output end of the driving power source;
  • the second thin film transistor T2 has a gate connected to the first control line, a source connected to the second end of the storage capacitor Cs, and a drain connected to the high level output end of the driving power source;
  • the third thin film transistor T3 has a gate connected to the first control line, a drain connected to the drain of the driving thin film transistor DTFT, and a source connected to the gate of the driving thin film transistor DTFT; the fourth film Transistor T4, the gate is connected to the first control line, and the source is connected to the data line. a drain connected to a cathode of the OLED;
  • the fifth thin film transistor T5 has a gate connected to the second control line, a source connected to the second end of the storage capacitor, and a drain connected to the source of the driving thin film transistor DTFT;
  • the sixth thin film transistor T6 has a gate connected to the second control line, a source connected to the cathode of the OLED, and a drain connected to the low level output end of the driving power source;
  • the second thin film transistor T2, the third thin film transistor T3, and the fourth thin film transistor T4 are n-type thin film transistors, and the first thin film transistor T1, the fifth thin film transistor T5, and the sixth thin film transistor T6 a p-type thin film transistor;
  • the output voltage of the high-level output terminal of the driving power source is VDD, and the output voltage of the low-level output terminal of the driving power source is VSS;
  • the defect is a node connected to the second end of the storage capacitor Cs, and the G point is a node connected to the first end of the storage capacitor Cs.
  • the pixel unit driving circuit according to the sixth embodiment of the present invention is based on the pixel unit driving circuit according to the fourth embodiment of the present invention.
  • the first switching element 20 is a first thin film transistor T1
  • the charging control unit 22 includes a second thin film transistor T2, a third thin film transistor T3, and a fourth thin film transistor T4, and the driving control unit 21 includes a fifth thin film transistor.
  • the first thin film transistor T1 has a gate connected to the first control line, a drain connected to the drain of the driving thin film transistor DTFT, and a source connected to the high level output end of the driving power source;
  • the second thin film transistor ⁇ 2 has a gate connected to the first control line, a source connected to the low level output end of the driving power source, and a drain connected to the second end of the storage capacitor Cs;
  • the third thin film transistor T3 has a gate connected to the first control line, a drain connected to the drain of the driving thin film transistor DTFT, and a source connected to the gate of the driving thin film transistor DTFT;
  • the fourth film The transistor T4 has a gate connected to the first control line, a source connected to the data line, and a drain connected to the cathode of the OLED;
  • the fifth thin film transistor T5 has a gate connected to the second control line, a source connected to the second end of the storage capacitor, and a drain connected to the source of the driving thin film transistor DTFT;
  • the sixth thin film transistor T6 has a gate connected to the second control line, a source connected to the cathode of the OLED, and a drain connected to the low level output end of the driving power source;
  • the tube T4 is an n-type thin film transistor
  • the first thin film transistor T1, the fifth thin film transistor T5, and the sixth thin film transistor T6 are p-type thin film transistors
  • the output voltage of the high-level output terminal of the driving power source is VDD, and the output voltage of the low-level output terminal of the driving power source is VSS;
  • the defect is a node connected to the second end of the storage capacitor Cs, and the G point is the storage capacitor
  • the node to which the first end of the Cs is connected is connected.
  • FIG. 10A is an equivalent circuit diagram of the pixel unit driving circuit of the second embodiment in a first period of time
  • FIG. 10B is an equivalent circuit diagram of the pixel unit driving circuit of the second embodiment in a second period of time
  • FIG. 10C is an equivalent circuit diagram of the pixel unit driving circuit of the second embodiment in a third period of time
  • T1 in the first time period, that is, in the initial stage, T1, ⁇ 2, and ⁇ 3 are all turned off, and ⁇ 4, ⁇ 5, and ⁇ 6 are turned on.
  • the G point ie, The node connected to the gate of the DTFT is in a floating state, and the conduction of T5 will cause the floating G point potential to be seriously pulled down, so that the DTFT is turned on. If the DTFT is turned on in the previous stage, it will enter the work of this stage.
  • T1 is turned on
  • T2, ⁇ 3, ⁇ 4, ⁇ 5, ⁇ 6 are all turned off
  • the DTFT is also turned off, and is in a working stop state to avoid the switch due to switching.
  • T4 in the third period, T4, ⁇ 5, and ⁇ 6 are turned off, and T1, ⁇ 2, and ⁇ 3 are turned on, since the ⁇ point potential is hopped from VSS to VDD-Voled (Voled is the operating voltage of the OLED for this gray scale) , does not coincide with Vth-oled, and the gate of DTFT is floating, so the voltage of Vg jumps to Vdata-Vth- oled- I Vth
  • -VSS +VDD-Voled ) VSS+Vth_oled+ I Vth
  • the current I flowing through the DTFT has nothing to do with the threshold voltage Vth of the DTFT, so that the uniformity of the current can be improved to achieve uniform brightness; while the current I flowing through the DTFT includes Vth-oled.
  • Vth-oled As the use time prolongs, the aging efficiency of the OLED material decreases, Vth-oled rises, and the rise of Vth-oled increases the operating current accordingly, thus improving the panel brightness reduction caused by material aging.
  • 11A is an equivalent circuit diagram of the pixel unit driving circuit of the third embodiment in a first period of time
  • FIG. 11B is an equivalent circuit diagram of the pixel unit driving circuit of the third embodiment in a second period of time
  • Fig. 11C is an equivalent circuit diagram of the pixel unit driving circuit of the third embodiment in the third period.
  • Vdata In the pixel unit driving circuit according to the second embodiment of the present invention, Vdata must be a negative voltage having a large absolute value to cause the entire circuit to emit light, otherwise the DTFT cannot be turned on, and the pixel according to the third embodiment of the present invention. This limitation is not present in the unit driver circuit. Vdata requires only a small positive voltage to turn the DTFT on and operate normally.
  • the operation timing of the pixel unit driving circuit according to the second embodiment of the present invention is still applicable to the pixel unit driving circuit according to the third embodiment of the present invention, and the operation of the circuit is also completely the same, which is only the third embodiment of the present invention.
  • Pixel unit drive circuit at During the three time period, the P point potential changes from VDD to VDD-Voled (Voled is the operating voltage of the OLED for this gray scale, which is inconsistent with Vth-oled), and the gate of the DTFT is floating), so the G point potential Vg jumps to Vdata-Vth- oled- I Vth
  • - Voled) VDD- Vdata+Vth_oled+ I Vth
  • , Current through the DTFT I K(Vsg- I Vth
  • f
  • I K(VDD- Vdata+Vth oled) 2 ;
  • K is the current coefficient of the DTFT;
  • ⁇ . ⁇ ⁇ ⁇ ⁇ ; ⁇ , C ox , W . J are the carrier mobility of the DTFT, the capacitance per unit area of the gate insulating layer, the channel width, and the channel length.
  • the pixel unit driving circuit according to the fifth embodiment of the present invention and the pixel unit driving circuit according to the sixth embodiment of the present invention are in operation, the first control signal S1, the second control signal S2, and the A timing diagram of the output signal Vdata of the data line.
  • the pixel unit driving circuit of the fifth embodiment of the present invention only converts the DTFT into an n-type thin film transistor, and the source of the DTFT and the anode of the OLED. Connection, the working process of the circuit is exactly the same, but the bottom light has a problem of aperture ratio.
  • Vdata In the pixel unit driving circuit of the fifth embodiment of the present invention, Vdata must also be a large positive voltage to turn on the DTFT, and the pixel unit driving circuit according to the sixth embodiment of the present invention overcomes this. Problem, in the pixel unit driving circuit according to the sixth embodiment of the present invention, Vdata only needs a small positive voltage to turn on the DTFT, so that the circuit works normally.
  • Vg jumps to Vdata+Vth_oled+Vth+VSS+ Voled- VDD
  • ⁇ . ⁇ ⁇ ⁇ ⁇ ; ⁇ , C ox , W . J are the carrier mobility of the DTFT, the capacitance per unit area of the gate insulating layer, the channel width, and the channel length.
  • Vth oled-VSS Vth oled-VSS 2 ;
  • K is the current coefficient of the DTFT
  • ⁇ . ⁇ ⁇ ⁇ ⁇ ; ⁇ , C ox , W . J are the carrier mobility of the DTFT, the capacitance per unit area of the gate insulating layer, the channel width, and the channel length.
  • a pixel unit driving circuit according to a third embodiment of the present invention, a sixth embodiment of the present invention, in comparison with the pixel unit driving circuit of the second embodiment of the present invention, the pixel unit driving circuit according to the fifth embodiment of the present invention
  • the pixel unit driving circuit described in the example reduces the voltage value of the data voltage Vdata, and reduces the power consumption of the pixel unit driving circuit, and also reduces the complexity of the pixel unit driving circuit.
  • the most characteristic feature of the pixel unit driving circuit of the present invention is that the data voltage Vdata is input from the source of the DTFT, and the self-discharge of the DTFT diode is used to connect Vth (the threshold voltage of the DTFT), Vdata (data voltage), Vth_oled (OLED light emission).
  • the threshold voltage is stored in the storage capacitor Cs to compensate the threshold voltage of the driving thin film transistor of the OLED, and the OLED is compensated by the voltage feedback mechanism.
  • the present invention also provides a pixel unit driving method, which is applied to the pixel unit described above. a driving circuit, the pixel unit driving method comprising the following steps:
  • Pixel charging step the charging control unit first controls the driving of the driving thin film transistor, and controls charging of the storage capacitor until the gate potential of the driving thin film transistor is raised to make the driving thin Membrane transistor cutoff;
  • Driving the OLED light emitting display step the driving control unit controls the driving thin film transistor to be turned on and the gate thereof is in a floating state to drive the OLED light emitting display and make the gate-source voltage of the driving thin film transistor compensate the threshold value of the driving thin film transistor Voltage.
  • the present invention also provides a pixel unit including an OLED and the pixel unit driving circuit of the first embodiment, the second embodiment, and the third embodiment;
  • the pixel unit driving circuit includes a source of a driving thin film transistor connected to a cathode of the OLED, and an anode of the OLED is connected to a high level output end of the driving power source through the driving control unit, where the driving thin film transistor is The drain is connected to the low level output of the driving power source through the first switching element.
  • the present invention further provides a pixel unit including an OLED and the pixel unit driving circuit of the fourth embodiment, the fifth embodiment, and the sixth embodiment;
  • a source of the driving thin film transistor included in the pixel unit driving circuit is connected to an anode of the OLED, and a cathode of the OLED is connected to a low level output end of the driving power source through the driving control unit, where the driving thin film transistor The drain is connected to the high level output terminal of the driving power source through the first switching element.
  • the source s and the drain g of the above various thin film transistors are manufactured in the same process, and are interchangeably named. Change the name according to the direction of the voltage.
  • the types of the transistors in the same pixel circuit may be the same or different, and it is only necessary to adjust the timing high and low levels of the corresponding gate-on signal source according to the characteristics of its own threshold voltage.
  • the preferred method is that the types of transistors that require the same gate-on signal source are the same.
  • all of the thin film transistors are of the same type (including a thin film transistor as a switching element, a driving thin film transistor, and a matching thin film transistor), and are both an n-type thin film transistor or a p-type thin film transistor.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Electroluminescent Light Sources (AREA)
  • Control Of El Displays (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)

Abstract

Un circuit d'entraînement d'unité de pixel, un procédé d'entraînement d'unité de pixel et une unité de pixel sont décrits. Le circuit d'entraînement d'unité de pixel comprend un transistor à film mince de commande (DTFT), un premier élément (10) de commutation, un condensateur (Cs) de stockage, une unité(11) de commande d'entraînement et une unité (12)de commande de charge. L'électrode de grille du transistor à film mince de commande (DTFT) est reliée à la première extrémité du condensateur (Cs) de stockage, et est en outre connectée à l'électrode de drain du transistor à film mince de commande (DTFT) à travers l'unité (12) de commande de charge. L'électrode de source du transistor à film mince de commande (DTFT) est reliée à la première extrémité d'une Diode Électroluminescente Organique (OLED), et est connectée à la seconde extrémité du condensateur (Cs) de stockage à travers l'unité(11) de commande d'entraînement. L'électrode de drain du transistor à film mince de commande (DTFT) est reliée à la première extrémité (VDD) d'une alimentation électrique d'entraînement à travers le premier élément (10) de commutation. La seconde extrémité du condensateur (Cs) de stockage est reliée à la première extrémité (VDD) de l'alimentation électrique d'entraînement à travers l'unité (12) de commande de charge. La seconde extrémité de l'OLED est reliée à la deuxième extrémité (VSS) de l'alimentation électrique d'entraînement à travers l'unité (11) de commande d'entraînement. La seconde extrémité de l'OLED est connectée à une ligne (Vdata) de données à travers l'unité (12) de commande de charge. Le circuit d'entraînement d'unité de pixel, le procédé d'entraînement d'unité de pixel et l'unité de pixel compensent la tension seuil du transistor à film mince de commande (DTFT), et compensent la chute du courant d'entraînement due au vieillissement du matériau de l'OLED.
PCT/CN2012/084015 2012-02-27 2012-11-02 Circuit d'entraînement d'unité de pixel, procédé d'entraînement d'unité de pixel et unité de pixel Ceased WO2013127189A1 (fr)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107967897A (zh) * 2013-12-05 2018-04-27 伊格尼斯创新公司 像素电路和提取电路参数并提供像素内补偿的方法

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102708793B (zh) * 2012-02-27 2014-02-19 京东方科技集团股份有限公司 像素单元驱动电路、像素单元驱动方法以及像素单元
CN103226931B (zh) 2013-04-27 2015-09-09 京东方科技集团股份有限公司 像素电路和有机发光显示器
CN103700346B (zh) * 2013-12-27 2016-08-31 合肥京东方光电科技有限公司 像素驱动电路、阵列基板、显示装置和像素驱动方法
US20160063921A1 (en) * 2014-08-26 2016-03-03 Apple Inc. Organic Light-Emitting Diode Display With Reduced Capacitive Sensitivity
CN104575393B (zh) * 2015-02-03 2017-02-01 深圳市华星光电技术有限公司 Amoled像素驱动电路及像素驱动方法
CN104715725A (zh) * 2015-04-03 2015-06-17 京东方科技集团股份有限公司 像素电路、显示装置及其驱动方法
CN106531083A (zh) * 2016-12-15 2017-03-22 上海天马有机发光显示技术有限公司 像素电路的补偿方法、oled显示面板及其补偿方法
CN108446051B (zh) * 2018-03-16 2020-10-30 深圳市华星光电技术有限公司 阵列基板及触控显示装置
CN113077761B (zh) * 2020-01-06 2022-12-09 京东方科技集团股份有限公司 像素电路、像素驱动方法和显示装置
CN113450695A (zh) * 2020-05-07 2021-09-28 重庆康佳光电技术研究院有限公司 一种MicroLED像素电路、时序控制方法及显示器
CN113516942B (zh) * 2020-05-14 2022-05-13 合肥联宝信息技术有限公司 一种显示控制方法以及驱动电路

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070126680A1 (en) * 2005-12-02 2007-06-07 Samsung Electronics Co., Ltd Display device and method for driving the same
US20070200793A1 (en) * 2006-02-28 2007-08-30 Oh Kyong Kwon Organic light emitting display device and driving method
CN101192374A (zh) * 2006-11-27 2008-06-04 奇美电子股份有限公司 有机发光显示面板及其电压驱动有机发光像素
JP2011013261A (ja) * 2009-06-30 2011-01-20 Kyocera Corp 画像表示装置および画像表示装置の駆動方法
CN102314829A (zh) * 2010-06-30 2012-01-11 三星移动显示器株式会社 像素和使用该像素的有机发光显示装置
CN102708793A (zh) * 2012-02-27 2012-10-03 京东方科技集团股份有限公司 像素单元驱动电路、像素单元驱动方法以及像素单元

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070126680A1 (en) * 2005-12-02 2007-06-07 Samsung Electronics Co., Ltd Display device and method for driving the same
US20070200793A1 (en) * 2006-02-28 2007-08-30 Oh Kyong Kwon Organic light emitting display device and driving method
CN101192374A (zh) * 2006-11-27 2008-06-04 奇美电子股份有限公司 有机发光显示面板及其电压驱动有机发光像素
JP2011013261A (ja) * 2009-06-30 2011-01-20 Kyocera Corp 画像表示装置および画像表示装置の駆動方法
CN102314829A (zh) * 2010-06-30 2012-01-11 三星移动显示器株式会社 像素和使用该像素的有机发光显示装置
CN102708793A (zh) * 2012-02-27 2012-10-03 京东方科技集团股份有限公司 像素单元驱动电路、像素单元驱动方法以及像素单元

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107967897A (zh) * 2013-12-05 2018-04-27 伊格尼斯创新公司 像素电路和提取电路参数并提供像素内补偿的方法

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