WO2014190614A1 - 发光二极管像素单元电路和显示面板 - Google Patents

发光二极管像素单元电路和显示面板 Download PDF

Info

Publication number
WO2014190614A1
WO2014190614A1 PCT/CN2013/080848 CN2013080848W WO2014190614A1 WO 2014190614 A1 WO2014190614 A1 WO 2014190614A1 CN 2013080848 W CN2013080848 W CN 2013080848W WO 2014190614 A1 WO2014190614 A1 WO 2014190614A1
Authority
WO
WIPO (PCT)
Prior art keywords
thin film
film transistor
node
gate
switching element
Prior art date
Application number
PCT/CN2013/080848
Other languages
English (en)
French (fr)
Inventor
青海刚
祁小敬
Original Assignee
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
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 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 filed Critical 京东方科技集团股份有限公司
Priority to US14/371,510 priority Critical patent/US9318540B2/en
Publication of WO2014190614A1 publication Critical patent/WO2014190614A1/zh

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0416—Control or interface arrangements specially adapted for digitisers
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0412—Digitisers structurally integrated in a display
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means
    • G06F3/0443—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means using a single layer of sensing electrodes
    • 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]
    • 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
    • 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
    • H10K59/121—Active-matrix OLED [AMOLED] displays characterised by the geometry or disposition of pixel elements
    • H10K59/1213—Active-matrix OLED [AMOLED] displays characterised by the geometry or disposition of pixel elements the pixel elements being TFTs
    • 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
    • H10K59/121—Active-matrix OLED [AMOLED] displays characterised by the geometry or disposition of pixel elements
    • H10K59/1216—Active-matrix OLED [AMOLED] displays characterised by the geometry or disposition of pixel elements the pixel elements being capacitors
    • 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
    • H10K59/40—OLEDs integrated with touch screens
    • 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
    • G09G2300/04—Structural and physical details of display devices
    • G09G2300/0421—Structural details of the set of electrodes
    • G09G2300/043—Compensation electrodes or other additional electrodes in matrix displays related to distortions or compensation signals, e.g. for modifying TFT threshold voltage in column driver
    • 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
    • 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
    • G09G2300/0876—Supplementary capacities in pixels having special driving circuits and electrodes instead of being connected to common electrode or ground; Use of additional capacitively coupled compensation electrodes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0233—Improving the luminance or brightness uniformity across the screen
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2354/00—Aspects of interface with display user

Definitions

  • the present invention relates to the field of display technologies, and in particular, to an LED pixel unit circuit and a display panel. Background technique
  • the active matrix-Organic Light Emitting Diode (AMOLED) display panel Compared with the conventional liquid crystal panel, the active matrix-Organic Light Emitting Diode (AMOLED) display panel has the characteristics of faster response speed, higher contrast ratio and wider viewing angle.
  • the pixels of the AMOLED display panel are driven by the relevant driving circuit on the array (Array) substrate for illumination display.
  • Array array
  • FIG. 1 shows a prior art 2T1C pixel driving circuit. As can be seen from FIG.
  • the prior art 2T1C pixel driving circuit includes two thin film transistors (TFTs, Thin-Film Transistors) and one capacitor, wherein the thin film transistor M1 functions as a switch for controlling data lines and The connection of the gate of the thin film transistor DTFT, the thin film transistor DTFT is a driving thin film transistor, which can generate a driving current under saturation, driving
  • AMOLED light. 2 is a timing chart of the scan signal G(n) on the scan line of the pixel driving circuit shown in FIG. 1 and the gray scale voltage signal Vd on the data line.
  • the scan signal is low level, the thin film transistor M1 is turned on, and the data is turned on.
  • the gray scale voltage Vd on the line charges the capacitor C.
  • the scan signal is high, the thin film transistor M1 is turned off, and the capacitor C is used to store the gray scale voltage. Since the power supply voltage VDD potential is high, the DTFT is in a saturated state.
  • the driving current I of the OLED is:
  • Vsg is the gate-to-source voltage of the DTFT
  • Vth is the threshold voltage of the DTFT
  • VDD is the positive voltage of the power supply
  • Vd is the grayscale voltage on the data line
  • K is a constant related to the transistor size and carrier mobility, once The TFT size and process are determined, K is determined.
  • the embodiment of the invention provides an LED pixel unit circuit and a display panel for solving the problem of uneven brightness of the display panel caused by different threshold voltages of the driving thin film transistors.
  • the embodiment of the present invention provides a light emitting diode pixel unit circuit, the circuit includes a driving module and a light emitting diode, wherein the driving module includes: a driving thin film transistor, a first switching element, a second switching element, a first capacitor, and Drive control unit
  • the gate of the driving thin film transistor is connected to the first node, the source is connected to the positive voltage output end of the power source, and the drain is connected to the anode of the light emitting diode;
  • the cathode of the light emitting diode is connected to a negative voltage output end of the power source;
  • the first capacitor is located between the first node and a second node that is the first connection end of the drive control unit;
  • the first switching element is connected in series between a third node that is a second connection end of the driving control unit and a data line;
  • the second switching element is connected in series between the positive voltage output of the power source and the first node;
  • the driving control unit includes a matching thin film transistor having a threshold voltage matched with a threshold voltage of the driving thin film transistor, located between the first switching element and the first capacitor, for controlling charging and discharging of the first capacitor, and clearing the first
  • the threshold voltage of the matching thin film transistor in the drive control unit and the new data voltage are written into the first capacitor while the original data voltage in the capacitor is being compensated to compensate the threshold voltage of the driving thin film transistor.
  • the drive control unit further includes a third switching element and a fifth switching element; wherein the third switching element is connected in series between the third node and the second node; the matching thin film transistor acts as a fourth The switching element is connected in anti-parallel with the third switching element, and is disposed between the third node and the second node; the fifth switching element is connected in series between the second node and the reference voltage output terminal.
  • the circuit further includes a sensing module, the sensing module includes a sixth switching element, a seventh switching element, a second capacitor, an amplifying thin film transistor, and an inductive element; the sixth switching element is connected in series at the first node And between the gate of the amplifying thin film transistor; the seventh switching element is connected in series between the drain of the amplifying thin film transistor and the sensing line; the second capacitor is connected in series to control the gate of the amplifying thin film transistor and the seventh switching element
  • the sensing element is connected to the gate of the amplifying thin film transistor; the sensing module multiplexes the positive voltage of the power supply in the driving module and the scan signal for charging and discharging by controlling the second capacitor in the sensing module, so that The touch signal of the finger can be amplified by the amplifying thin film transistor in the sensing module.
  • the first to seventh switching elements are first to seventh open thin film transistors.
  • the gate of the first thin film transistor is connected to the scan signal of the pixel of the row, the source is connected to the data line, and the drain is connected to the third node; the gate of the second thin film transistor is connected with the scan signal of the pixel of the row.
  • a source is connected to the power positive voltage output terminal, and a drain is connected to the first node; a gate and a drain of the third thin film transistor are simultaneously connected to the second node, and a source is connected to the third node; The gate and the drain of the transistor are simultaneously connected to the third node, and the source is connected to the second node; the gate of the fifth thin film transistor is connected to the control signal of the pixel of the row, the source is connected to the second node, and the drain is connected to the reference voltage Output.
  • the gate of the sixth thin film transistor is connected to the scan signal of the pixel of the row, the source is connected to the first node, and the drain is connected to the gate of the amplified thin film transistor; the gate of the seventh thin film transistor is connected to the scan signal of the next row of pixels
  • the source is connected to the drain of the amplifying thin film transistor, and the drain is connected to the sensing line; the gate of the amplifying thin film transistor is connected to the drain of the sixth thin film transistor, the source is connected to the positive voltage of the power source, and the drain is connected to the source of the seventh thin film transistor. pole.
  • the fourth thin film transistor is the same size and shape as the driving thin film transistor.
  • the fourth thin film transistor may be disposed adjacent to the driving thin film transistor according to the principle that the two thin film transistors of the same design are more compatible (ie, inside the same pixel, two identical designs) Since the thin film transistors are in close proximity to each other and the process environment is also very uniform, the electrical difference caused by the process is very small and can be approximately the same, in other words, the threshold voltage of the fourth thin film transistor and the threshold voltage of the driving thin film transistor. Approximately the same), used to compensate the threshold voltage of the driving thin film transistor, and eliminate the influence of the threshold voltage of the driving thin film transistor on the driving current.
  • all of the thin film transistors are P-type thin film transistors.
  • the thin film transistors are all polysilicon thin film transistors, or both are amorphous silicon thin film transistors, or both are oxide thin film transistors.
  • the sensing element is an inductive electrode for forming a sensing capacitance with a human body when a person touches the sensing electrode.
  • Embodiments of the present invention provide a display panel, which includes the above-described LED pixel unit circuit.
  • the pixel unit circuit provided by the embodiment of the invention includes a driving module and a sensing module, wherein the driving module is provided with a driving thin film transistor, a first switching element, a first capacitor, a second switching element and a driving control unit, and is controlled by the driving The unit charges and discharges the first capacitor, and writes the threshold voltage of the matching thin film transistor and the new data voltage into the first capacitor while clearing the original data voltage.
  • the driving module is provided with a driving thin film transistor, a first switching element, a first capacitor, a second switching element and a driving control unit, and is controlled by the driving
  • the unit charges and discharges the first capacitor, and writes the threshold voltage of the matching thin film transistor and the new data voltage into the first capacitor while clearing the original data voltage.
  • the reference voltage is introduced by the driving control module, since the reference voltage source is only used in the circuit
  • a reference reference is used to provide a level reference to the first node without continuous current flowing through the line, so that the internal resistance of the line does not cause the reference level to drop after reaching the first node, so the reference voltage acts as a voltage
  • the value appears in the current formula, whether it is the working phase or the non-working phase of the circuit is constant, thus eliminating the influence of the internal resistance of the line on the lighting circuit, so that the driving current of the LED in the pixel circuit is the same gray level voltage. Consistently, the brightness of the display panel using the circuit does not differ, thereby improving the uniformity of the brightness of the display panel.
  • 1 is a 2T1C pixel driving circuit in the prior art
  • 2 is a signal timing diagram of each signal terminal of the 2T1C pixel driving circuit
  • FIG. 3 is a circuit diagram of a pixel driving circuit according to an embodiment of the present invention.
  • FIG. 4 is a signal timing diagram of each signal terminal in a pixel driving circuit according to an embodiment of the present invention
  • FIG. 5 is a first phase equivalent circuit diagram of a pixel driving circuit according to an embodiment of the present invention
  • FIG. 7 is a third stage equivalent circuit diagram of the pixel driving circuit according to the embodiment of the present invention.
  • Embodiments of the present invention provide an LED pixel unit circuit and a display panel for solving the problem of uneven brightness of a display panel caused by different threshold voltages of driving a thin film transistor.
  • FIG. 3 is an active matrix organic light emitting diode (AMOLED) pixel unit circuit according to an embodiment of the present invention.
  • the circuit includes: a driving module 31, a sensing module 32, and a light emitting diode 33.
  • the driving module 31 includes: a driving thin film transistor DTFT, a first thin film transistor T1, a second thin film transistor ⁇ 2, a first capacitor C1, and a driving control unit 311; wherein the driving control unit 311 includes a third thin film transistor ⁇ 3, a fourth thin film transistor ⁇ 4 and a fifth thin film transistor ⁇ 5.
  • the gate of the driving thin film transistor DTFT is connected to the first node PI, and the source is connected to the positive voltage of the power source
  • the VDD output terminal is connected to the anode of the active matrix organic light emitting diode AMOLED.
  • the first capacitor CI is located between the first node PI and the second node P2.
  • the gate of the first thin film transistor T1 is connected to the scan signal G(n) of the pixel of the row, the source is connected to the data line Ldata, and the drain is connected to the third node P3.
  • the gate of the second thin film transistor T2 is connected to the scan signal G(n) of the pixel of the row, the source is connected to the output terminal of the power positive voltage VDD, and the drain is connected to the first node P1.
  • the gate and the drain of the third thin film transistor T3 are simultaneously connected to the second node P2, and the source is connected to the third node P3.
  • the gate and the drain of the fourth thin film transistor T4 are simultaneously connected to the third node P3, and the source is connected to the second node P2.
  • the gate of the fifth thin film transistor T5 is connected to the control signal C(n) of the pixel of the row, the source is connected to the second node P2, and the drain is connected to the reference voltage output terminal Vref.
  • the sensing module 32 includes: a sixth thin film transistor T6, a seventh thin film transistor ⁇ 7, an amplifying thin film transistor ATFT, a second capacitor C2, and a sensing electrode 321 .
  • the gate of the sixth thin film transistor T6 is connected to the scan signal G(n) of the pixel of the row, the source is connected to the first node P1, and the drain is connected to the gate of the amplifying thin film transistor ATFT.
  • the gate of the seventh thin film transistor T7 is connected to the scanning signal G(n+1) of the pixel of the next row, the source is connected to the drain ATFT of the amplifying thin film transistor, and the drain is connected to the sensing line Lsense.
  • the second capacitor C2 is connected between the gate of the amplifying thin film transistor ATFT and the gate of the seventh thin film transistor T7.
  • the sensing electrode 321 is connected to the gate of the amplifying thin film transistor ATFT, and is used to form a sensing capacitor Cf with the human body when the human touches the sensing electrode, causing a change in the potential of the gate of the amplifying thin film transistor ATFT to generate a change induction. Current.
  • the anode of the active matrix organic light emitting diode AMOLED is connected to drive the drain of the thin film transistor DTFT, and the cathode is connected to the negative voltage VSS of the power supply.
  • FIG. 4 is a timing diagram of each signal terminal. The working method of the active matrix OLED pixel unit circuit according to the embodiment of the present invention is described below with reference to FIG. 4, wherein all the thin film transistors are low-level conduction, high level. cutoff.
  • FIG. 5 is an equivalent circuit diagram of the stage; the scanning signal G(n+1) of the next row of pixels is at a high level VGH, so that the scanning signal G (n+) in response to the next row of pixels
  • the seventh thin film transistor T7 of 1) is turned off, and the drain of the amplifying thin film transistor ATFT is in a vacant state.
  • the scanning signal G ( n ) of the pixel of the line is a low level VGL, and the control signal C ( n ) of the pixel of the line a high level VGH, the first thin film transistor T1, the second thin film transistor ⁇ 2 and the sixth thin film transistor ⁇ 6 are turned on, the fifth thin film transistor ⁇ 5 is turned off; the gray line voltage signal Vd is output on the data line, the gray scale voltage signal The gray scale voltage corresponding to Vd is Vh, and the Vh is high level, so the fourth thin film transistor T4 is turned off; since the potential of the second node P2 is low, the third thin film transistor T3 is turned on, at this time, the data line
  • the voltage Vh charges the first capacitor C1 through the first thin film transistor T1 and the third thin film transistor T3, so that the potential of the second node P2 rises to Vh-IVth31, wherein the IVth31 is the threshold of the third thin film transistor T3.
  • the power supply positive voltage VDD charges the first capacitor C1 through the second thin film transistor T2, so that the potential of the first node P1 rises to VDD, and the power supply positive voltage VDD passes through the second thin film transistor T2 and the sixth thin film transistor T6.
  • the second capacitor C2 is charged so that the gate potential of the fourth node P4, that is, the amplifying thin film transistor ATFT, rises to VDD.
  • the second stage S2 see Figure 6, Figure 6 is the equivalent circuit diagram of this stage; G ( n ) remains low, C ( n ) and G ( n+1 ) remain high, the voltage on the data line is from The high level Vh jumps to the low level Vdata, and therefore, the first thin film transistor T1, the second thin film transistor ⁇ 2, and the sixth thin film transistor ⁇ 6 are kept turned on, the fifth thin film transistor ⁇ 5 is turned off, and the seventh thin film transistor ⁇ 7 is kept turned off. Since the first capacitor C1 is charged in the previous stage, the potential of the second node ⁇ 2 rises to
  • Vh-IVth3l after the voltage on the data line jumps to Vdata, the potential of the third node P3 is lowered, the third thin film transistor T3 is turned off, the fourth thin film transistor T4 is turned on, and the first capacitor C1 is passed through the fourth thin film transistor T4. Gradually discharging, when the potential of the third node P3 falls to Vdata+IVth4l, the fourth thin film transistor T4 is turned off, wherein the IVth41 is the threshold voltage of the fourth thin film transistor T4.
  • Vcl VDD- ( Vdata+IVth4l );
  • the voltage Vc2 across the second capacitor is:
  • Vc2 VDD - VGH.
  • the third stage S3, see Figure 7, Figure 7 is the equivalent circuit diagram of this stage; G ( n ) jumps to high level VGH, C ( n ) jumps to low level.
  • the first thin film transistor T1, the second thin film transistor ⁇ 2 and the sixth thin film transistor ⁇ 6 are turned off, and the fifth thin film transistor ⁇ 5 is turned on; since the first node P1 is in a floating state, the voltage on the first capacitor C1 remains unchanged, but The fifth thin film transistor ⁇ 5 is turned on, so that the potential at the second node ⁇ 2 rises to Vref, and at the same time, due to the coupling of the first capacitor For cooperation, the potential at the gate of the first node PI, that is, the gate of the driving thin film transistor DTFT also changes. At this time, the potential of the gate of the driving TFTD DTFT is:
  • Vg is the potential of driving the gate of the thin film transistor DTFT
  • Vpl is the potential at the first node
  • Vref is the reference voltage
  • the gate-to-source voltage of the DTFT is:
  • Vsg Vs-Vg
  • Vsg is the gate-source voltage of the driving thin film transistor DTFT
  • Vs is the driving thin film transistor
  • the source voltage of the DTFT is the same as the DTFT.
  • the fourth thin film transistor T4 is a matching thin film transistor that drives the thin film transistor DTFT, the threshold voltages of the two are approximately equal, and thus the saturation current of the thin film transistor DTFT is driven, that is, the light emission current I of the OLED. Led is:
  • I oled K d (Vsg-l Vthd I) 2
  • K d is a constant related to the process and drive design.
  • G ( n+1 ) jumps to a low level VGL, so that the seventh thin film transistor T7 is turned on; since the sixth thin film transistor T6 is turned off, the gate of the amplifying thin film transistor ATFT is suspended, so when G(n+1) When the potential jumps to a low level, the gate potential of the fourth node P4, that is, the amplified thin film transistor ATFT, also jumps downward by the coupling action of the second capacitor C2.
  • the magnitude of the change in the gate potential of the ATFT of the amplifying thin film transistor is related to whether or not a touch action occurs on the sensing electrode 321 connected to the gate thereof.
  • the coupling capacitance Cf is formed between the human body and the sensing electrode 321, so that the potential of the fourth node P4 is:
  • Vp4 [VDD+ ( VGL-VGH ) ]* C2/(C2+Cf)
  • Vp4 is the potential of the fourth node P4.
  • VDD-[ [VDD+ ( VGL-VGH ) ]* C2/(C2+Cf)] VDD* Cf/(C2+Cf) + ( VGH-VGL ) * C2/(C2+Cf)
  • the magnitude of the induced current Ise passing through the sensing line Lsense is:
  • Vtha the threshold voltage of the amplifier tube
  • Ka the amplifier tube related to the process and design constant.
  • Vp4 VDD - (VGH - VGL )
  • the magnitude of the induced current Ise passing through the sensing line Lsense is:
  • the embodiment of the invention further provides a display panel, which comprises the above-mentioned active matrix organic light emitting diode AMOLED pixel unit circuit.
  • the active matrix AMOLED pixel unit circuit provided by the embodiment of the present invention includes a driving module and a sensing module.
  • the driving module is provided with a driving thin film transistor, a first switching element, a first capacitor, and a second switching element.
  • Driving the control unit by charging and discharging the first capacitor by the driving control unit, writing the threshold voltage of the matching thin film transistor and the new data voltage into the first capacitor while eliminating the original data voltage, thereby compensating the threshold of the driving thin film transistor
  • the voltage causes the driving current for driving the light emitting diode to be unaffected by the threshold voltage of the driving thin film transistor, and at the same time, the reference voltage is introduced by the driving control module to eliminate the influence of the internal resistance of the line on the light emitting circuit, so that the pixel circuit In the same gray-scale voltage, the driving current of the AMOLED is consistent, and the brightness of the display panel using the circuit is not different, thereby improving the brightness of the display panel. Uniformity.
  • the present invention further integrates the touch module in the circuit, and multiplexes the power supply positive voltage VDD in the driving module and the scanning signals G(n), G(n+1) of the pixels of the row and the pixels of the next row.
  • the utility model is characterized in that the second capacitor in the sensing module is charged and discharged, so that the touch signal of the finger can be amplified by the amplifying transistor, and the touch of the display panel is well realized without increasing the circuit structure and the operation complexity.
  • a single P-type thin film transistor is used in the circuit, which reduces the complexity and cost of the fabrication process.
  • the above embodiment is described by taking a single P-type thin film transistor as an example, the above circuit can be easily changed to use a single N-type thin film transistor or a CMOS transistor circuit; The touch function portion is removed, and the driving touch circuit is changed to a pure pixel light emitting driving circuit.
  • the above description has been made by taking an active matrix organic light emitting diode as an example, the present invention is not limited to a display device using an active matrix organic light emitting diode, and can be applied to a display device using other various light emitting diodes. The spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of the inventions

Landscapes

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

Abstract

一种发光二极管像素单元电路和显示面板，所述电路包括驱动模块（31），所述驱动模块（31）中设置有驱动控制单元（311），所述驱动控制单元（311）包括阈值电压与驱动薄膜晶体管（DTFT）的阈值电压相匹配的匹配管（T4），其位于第一开关元件（T1）和第一电容（C1）之间，用于通过控制所述第一电容（C1）充放电，在清除第一电容（C1）中原来数据电压的同时将所述匹配管（T4）的阈值电压和新的数据电压写入第一电容（C1）中，从而补偿驱动薄膜晶体管（DTFT）的阈值电压。该电路可以解决因驱动薄膜晶体管（DTFT）的阈值电压不同所导致的显示面板亮度不均的问题，同时将触摸屏电路集成于像素单元电路中，实现发光二极管显示面板的触控功能。

Description

发光二极管像素单元电路和显示面板 技术领域
本发明涉及显示技术领域， 尤其涉及一种发光二极管像素单元电路和显 示面板。 背景技术
有源矩阵有机发光二极管 （AMOLED, Active Matrix-Organic Light Emitting Diode )显示面板相比传统的液晶面板， 具有反应速度较快、 对比度 更高、 视角较广等特点。 AMOLED显示面板的像素由阵列 （Array )基板上 相关驱动电路驱动进行发光显示， 参见图 1 , 图 1为现有技术中 2T1C像素驱 动电路。 从图 1中可以看出， 现有技术中 2T1C像素驱动电路包括两个薄膜 晶体管 （TFT, Thin-Film Transistor )和 1个电容， 其中， 薄膜晶体管 Ml起 到开关作用， 用于控制数据线与薄膜晶体管 DTFT的栅极的连接， 薄膜晶体 管 DTFT为驱动薄膜晶体管， 其在饱和状态下能够产生驱动电流， 驱动
AMOLED发光。 图 2为图 1所示像素驱动电路的扫描线上的扫描信号 G(n) 与数据线上的灰阶电压信号 Vd的时序图， 当扫描信号为低电平时， 薄膜晶 体管 Ml导通， 数据线上的灰阶电压 Vd对电容 C充电， 当扫描信号为高电 平时， 薄膜晶体管 Ml截止， 电容 C用于保存灰阶电压。 由于电源电压 VDD 电位较高， 因此 DTFT处于饱和状态， 此时， OLED的驱动电流 I为：
I=K(Vsg-IVthl)2= K(VDD-Vdata-IVthl)2
其中， Vsg为 DTFT的栅源电压， Vth为 DTFT的阈值电压， VDD为电源 正电压， Vd为数据线上的灰阶电压， K是一个与晶体管尺寸和载流子迁移率 有关的常数， 一旦 TFT尺寸和工艺确定， K确定。
但是在实际生产工艺过程中， 即便是使用相同的工艺参数， 制作出来的 显示面板的不同位置的 TFT的阈值电压也可能有较大差异， 使得所述不同位 置的 TFT的临界饱和电压也不同，导致在同一灰阶电压下 OLED的驱动电流 不一样， 使得采用该电路的显示面板不同位置的亮度会有差异， 亮度均一性 差。 发明内容 本发明实施例提供了一种发光二极管像素单元电路和显示面板， 用以解 决因驱动薄膜晶体管的阈值电压不同所导致的显示面板亮度不均的问题。
本发明实施例提供了一种发光二极管像素单元电路， 所述电路包括驱动 模块和发光二极管， 其中， 所述驱动模块包括： 驱动薄膜晶体管、 第一开关 元件、 第二开关元件、 第一电容和驱动控制单元；
所述驱动薄膜晶体管的栅极连接第一节点，源极连接电源正电压输出端， 漏极连接所述发光二级管的阳极；
所述发光二级管的阴极连接电源负电压输出端；
所述第一电容位于第一节点与作为驱动控制单元的第一连接端的第二节 点之间；
所述第一开关元件串联在作为驱动控制单元的第二连接端的第三节点和 数据线之间；
所述第二开关元件串联在电源正电压输出端和第一节点之间；
所述驱动控制单元包括阈值电压与驱动薄膜晶体管的阈值电压相匹配的 匹配薄膜晶体管， 位于第一开关元件和第一电容之间， 用于通过控制所述第 一电容充放电， 在清除第一电容中原来数据电压的同时将所述驱动控制单元 中的匹配薄膜晶体管的阈值电压和新的数据电压写入第一电容中从而补偿所 述驱动薄膜晶体管的阈值电压。
在一个示例中，所述驱动控制单元还包括第三开关元件和第五开关元件; 其中， 所述第三开关元件串联在第三节点和第二节点之间； 所述匹配薄膜晶 体管充当第四开关元件， 并与第三开关元件反向并联， 共同设置在第三节点 和第二节点之间；所述第五开关元件串联在第二节点和参考电压输出端之间。
在一个示例中， 所述电路还包括感应模块， 所述感应模块包括第六开关 元件、 第七开关元件、 第二电容、 放大薄膜晶体管和感应元件； 所述第六开 关元件串联在第一节点和放大薄膜晶体管的栅极之间； 所述第七开关元件串 联在放大薄膜晶体管的漏极和感应线之间； 所述第二电容串联在放大薄膜晶 体管的栅极与第七开关元件的控制端之间； 所述感应元件连接所述放大薄膜 晶体管的栅极； 所述感应模块复用驱动模块中的电源正电压以及扫描信号， 用于通过控制感应模块中的第二电容充放电， 使得手指的触控信号能被感应 模块中的放大薄膜晶体管放大。
在一个示例中， 所述第一至第七开关元件为第一至第七开薄膜晶体管。 所述第一薄膜晶体管的栅极与本行像素的扫描信号连接， 源极与数据线 连接， 漏极与第三节点连接； 所述第二薄膜晶体管的栅极与本行像素的扫描 信号连接， 源极与电源正电压输出端连接， 漏极与第一节点连接； 所述第三 薄膜晶体管的栅极与漏极同时连接第二节点， 源极与第三节点连接； 所述第 四薄膜晶体管的栅极与漏极同时连接第三节点， 源极与第二节点连接； 所述 第五薄膜晶体管的栅极连接本行像素的控制信号， 源极连接第二节点， 漏极 连接参考电压输出端。
所述第六薄膜晶体管的栅极连接本行像素的扫描信号， 源极连接第一节 点， 漏极连接放大薄膜晶体管的栅极； 所述第七薄膜晶体管的栅极连接下一 行像素的扫描信号， 源极连接放大薄膜晶体管的漏极， 漏极连接感应线； 所 述放大薄膜晶体管的栅极连接第六薄膜晶体管的漏极，源极连接电源正电压， 漏极连接第七薄膜晶体管的源极。
在一个示例中， 所述第四薄膜晶体管与所述驱动薄膜晶体管的尺寸和形 状相同。 实际工艺过程中， 可将所述第四薄膜晶体管设置在与驱动薄膜晶体 管邻近的位置， 根据两个相同设计的薄膜晶体管电性较匹配的原理（即， 在 同一像素内部， 两个相同设计的薄膜晶体管由于相互的位置非常接近， 工艺 环境也非常一致， 因此工艺上引起的电性差异非常小， 可以近似为相同， 换 而言之， 第四薄膜晶体管的阈值电压和驱动薄膜晶体管的阈值电压近似相 同）， 用于补偿驱动薄膜晶体管的阈值电压， 消除驱动薄膜晶体管的阈值电压 对驱动电流的影响。
在一个示例中， 所有薄膜晶体管均为 P型薄膜晶体管。
在一个示例中， 上述薄膜晶体管均为多晶硅薄膜晶体管， 或者均为非晶 硅薄膜晶体管， 或者均为氧化物薄膜晶体管。
在一个示例中，所述感应元件为感应电极，用于当人触摸该感应电极时， 与人体之间形成感应电容。
本发明实施例提供了一种显示面板， 所述显示面板包括上述的发光二极 管像素单元电路。
本发明实施例提供的像素单元电路包括驱动模块和感应模块， 所述驱动 模块中设置有驱动薄膜晶体管、 第一开关元件、 第一电容、 第二开关元件和 驱动控制单元， 通过所述驱动控制单元对第一电容的充放电， 在清除原来数 据电压的同时将匹配薄膜晶体管的阈值电压和新的数据电压写入第一电容中 从而补偿驱动管的阈值电压， 使得用于驱动发光二极管发光的驱动电流不受 驱动薄膜晶体管的阈值电压的影响， 同时， 通过所述驱动控制模块引入参考 电压， 由于参考电压源在电路中只作为一个参考基准用于对第一节点提供电 平参照而并无持续的电流从线路中流过， 因而线路的内阻并不引起参考电平 在到达第一节点后电位下降， 因而参考电压作为一个电压值出现在电流公式 中不管是电路工作阶段还是非工作阶段都是恒定的， 因而消除了线路内阻对 发光电路的影响， 使得在该像素电路中， 同一灰阶电压下发光二极管的驱动 电流是一致的， 采用该电路的显示面板的亮度不会有差异， 从而提高了显示 面板亮度的均一性。 附图说明
图 1为现有技术中 2T1C像素驱动电路；
图 2为 2T1C像素驱动电路各信号端的信号时序图；
图 3为本发明实施例提供的一种像素驱动电路的电路图；
图 4为本发明实施例提供的像素驱动电路中各信号端的信号时序图； 图 5为本发明实施例提供的像素驱动电路的第一阶段等效电路图； 图 6为本发明实施例提供的像素驱动电路的第二阶段等效电路图； 图 7为本发明实施例提供的像素驱动电路的第三阶段等效电路图。 具体实施方式
本发明实施例提供了一种发光二极管像素单元电路和显示面板， 用以解 决因驱动薄膜晶体管的阈值电压不同所导致的显示面板亮度不均的问题。
下面结合附图， 对本发明进行说明。
参见图 3, 图 3为本发明实施例提供的有源矩阵有机发光二极管 AMOLED 像素单元电路， 该电路包括： 驱动模块 31、 感应模块 32和发光二极管 33。
具体的， 所述驱动模块 31包括： 驱动薄膜晶体管 DTFT、 第一薄膜晶体管 Tl、 第二薄膜晶体管 Τ2、 第一电容 C1和驱动控制单元 311 ; 其中， 所述驱动 控制单元 311包括第三薄膜晶体管 Τ3、 第四薄膜晶体管 Τ4和第五薄膜晶体管 Τ5。
所述驱动薄膜晶体管 DTFT的栅极连接第一节点 PI ,源极连接电源正电压
VDD输出端， 漏极连接有源矩阵有机发光二级管 AMOLED的阳极。 所述第一电容 CI位于第一节点 PI与第二节点 P2之间。
所述第一薄膜晶体管 T1的栅极与本行像素的扫描信号 G(n)连接， 源极与 数据线 Ldata连接， 漏极与第三节点 P3连接。
所述第二薄膜晶体管 T2的栅极与本行像素的扫描信号 G(n)连接， 源极与 电源正电压 VDD输出端连接， 漏极与第一节点 P1连接。
所述第三薄膜晶体管 T3的栅极与漏极同时连接第二节点 P2, 源极与第三 节点 P3连接。
所述第四薄膜晶体管 T4的栅极与漏极同时连接第三节点 P3, 源极与第二 节点 P2连接。
所述第五薄膜晶体管 T5的栅极连接本行像素的控制信号 C(n), 源极连接 第二节点 P2, 漏极连接参考电压输出端 Vref。
具体的，所述感应模块 32包括： 第六薄膜晶体管 T6、第七薄膜晶体管 Τ7、 放大薄膜晶体管 ATFT、 第二电容 C2和感应电极 321。
所述第六薄膜晶体管 T6的栅极连接本行像素的扫描信号 G(n), 源极连接 第一节点 P1 , 漏极连接放大薄膜晶体管 ATFT的栅极。
所述第七薄膜晶体管 T7的栅极连接下一行像素的扫描信号 G(n+1), 源极 连接放大薄膜晶体管的漏极 ATFT , 漏极连接感应线 Lsense。
第二电容 C2连接在放大薄膜晶体管 ATFT的栅极和第七薄膜晶体管 T7的 栅极之间。
所述感应电极 321连接放大薄膜晶体管 ATFT的栅极， 用于当人触摸该 感应电极时， 与人体之间形成感应电容 Cf, 引起放大薄膜晶体管 ATFT的栅 极的电位发生变化， 产生变化的感应电流。
此外， 所述有源矩阵有机发光二级管 AMOLED的阳极连接驱动薄膜晶 体管 DTFT的漏极， 阴极连接电源负电压 VSS。
图 4为各信号端的时序图， 下面结合图 4对本发明实施例提供的有源矩 阵有机发光二极管像素单元电路的工作方法进行说明， 其中， 所有薄膜晶体 管均为低电平导通， 高电平截止。
第一阶段 S1 , 参见图 5, 图 5为该阶段的等效电路图； 下一行像素的扫 描信号 G ( n+1 )为高电平 VGH,使得响应于下一行像素的扫描信号 G ( n+1 ) 的第七薄膜晶体管 T7截止， 放大薄膜晶体管 ATFT的漏极处于空置状态。
本行像素的扫描信号 G ( n )为低电平 VGL, 本行像素的控制信号 C ( n ) 为高电平 VGH, 使得第一薄膜晶体管 Tl、 第二薄膜晶体管 Τ2和第六薄膜晶 体管 Τ6导通， 第五薄膜晶体管 Τ5截止； 数据线上输出灰阶电压信号 Vd, 所 述灰阶电压信号 Vd对应的灰阶电压大小为 Vh, 所述 Vh为高电平， 因此第 四薄膜晶体管 T4截止； 由于第二节点 P2的电位较低， 因此第三薄膜晶体管 T3导通，此时，数据线的电压 Vh通过所述第一薄膜晶体管 T1和第三薄膜晶 体管 T3对第一电容 C1充电， 使得第二节点 P2的电位上升至 Vh-IVth3l, 其 中，所述 IVth3l为第三薄膜晶体管 T3的阈值电压； 电源正电压 VDD通过第二 薄膜晶体管 T2对第一电容 C1充电， 使得第一节点 P1的电位上升至 VDD, 同时， 电源正电压 VDD通过所述第二薄膜晶体管 T2和第六薄膜晶体管 T6 对第二电容 C2充电， 使得第四节点 P4、 即放大薄膜晶体管 ATFT的栅极电 位上升至 VDD。
同时， 由于下一行像素的扫描信号 G ( n+1 ) 为高电平 VGH, 因此第五 节点 P5的电位上升至 VGH。
第二阶段 S2, 参见图 6, 图 6为该阶段的等效电路图； G ( n )保持低电 平， C ( n )和 G ( n+1 )保持高电平， 数据线上的电压从高电平 Vh跳变为低 电平 Vdata, 因此， 第一薄膜晶体管 Tl、 第二薄膜晶体管 Τ2和第六薄膜晶体 管 Τ6保持导通， 第五薄膜晶体管 Τ5截止和第七薄膜晶体管 Τ7保持截止。 由于在上一阶段中对第一电容 C1充电使得第二节点 Ρ2的电位上升至
Vh-IVth3l, 数据线上的电压跳变为 Vdata后， 使得第三节点 P3的电位降低， 第三薄膜晶体管 T3截止， 第四薄膜晶体管 T4开启， 第一电容 C1通过所述 第四薄膜晶体管 T4逐渐放电， 当第三节点 P3的电位下降至 Vdata+IVth4l时， 第四薄膜晶体管 T4截止，其中，所述 IVth4l为第四薄膜晶体管 T4的阈值电压。
此时， 第一电容两端的电压 Vcl为：
Vcl= VDD- ( Vdata+IVth4l );
第二电容两端的电压 Vc2为：
Vc2=VDD-VGH。
第三阶段 S3, 参见图 7, 图 7为该阶段的等效电路图； G ( n )跳变为高 电平 VGH, C ( n )跳变为低电平。 第一薄膜晶体管 Tl、 第二薄膜晶体管 Τ2 和第六薄膜晶体管 Τ6截止， 第五薄膜晶体管 Τ5导通； 由于第一节点 P1处 于悬空状态， 因此第一电容 C1上的电压保持不变，但是由于第五薄膜晶体管 Τ5的导通， 使得第二节点 Ρ2处的电位上升至 Vref, 同时由于第一电容的耦 合作用， 第一节点 PI处、 即驱动薄膜晶体管 DTFT栅极的电位也发生变化， 此时， 驱动薄膜晶体管 DTFT栅极的电位为：
Vg=Vpl=VDD+Vref- ( Vdata+IVth4l )
其中， Vg为驱动薄膜晶体管 DTFT栅极的电位， Vpl为第一节点处的电 位， Vref为参考电压。
驱动薄膜晶体管 DTFT的栅源电压为：
Vsg=Vs-Vg
=VDD-( VDD+Vref- ( Vdata+IVth4l ) )
= Vdata+IVth4l-Vref;
其中， Vsg为驱动薄膜晶体管 DTFT的栅源电压， Vs为驱动薄膜晶体管
DTFT的源极电压。
由于第四薄膜晶体管 T4为驱动薄膜晶体管 DTFT的匹配薄膜晶体管， 两者的阈值电压近似相等， 因此通过驱动薄膜晶体管 DTFT的饱和电流即 OLED的发光电流大小 I。led为：
Ioled=Kd(Vsg-l Vthd I)2
=Kd (Vdata+IVth4l-Vref -l Vthd I)2
= Kd (Vdata-Vref)2
其中， Kd为与工艺和驱动设计有关的常数。
此外， G ( n+1 )跳变为低电平 VGL, 使得第七薄膜晶体管 T7导通； 由 于第六薄膜晶体管 T6截止，放大薄膜晶体管 ATFT的栅极悬空，因此当 G(n+1) 电位跳变为低电平时， 通过第二电容 C2的耦合作用， 第四节点 P4处、 即放 大薄膜晶体管 ATFT的栅极电位也会跟着向下跳变。 所述放大薄膜晶体管 ATFT栅极电位变化的大小，跟连接在其栅极上的感应电极 321上是否有触摸 动作发生有关。
当在感应电极 321上有触摸动作发生时， 由于人体与感应电极 321之间 会形成耦合电容 Cf, 因此第四节点 P4的电位为：
Vp4= [VDD+ ( VGL-VGH ) ]* C2/(C2+Cf)
其中， Vp4为第四节点 P4的电位。
此时， 放大薄膜晶体管 ATFT的源极与栅极之间的电压 V^g为：
V!Sg=Vs-Vg= Vs-Vp4
=VDD-[ [VDD+ ( VGL-VGH ) ]* C2/(C2+Cf)] = VDD* Cf/(C2+Cf) + ( VGH-VGL ) * C2/(C2+Cf)
相应的， 此时通过感应线 Lsense的感应电流 Ise大小为：
Ise=Ka(Vsg- IVthal)2: Ka(ViSg- IVthal)2
= Ka[VDD* Cf/(C2+Cf) + (VGH-VGL)* C2/(C2+Cf) -IVthal]2 其中， Vtha为放大管的阈值电压， Ka为放大管与工艺和设计有关的常 数。
当在感应电极 321上没有有触摸动作发生时， 第四节点 P4的电位为： Vp4=VDD- ( VGH-VGL )
此时， 放大薄膜晶体管 ATFT的源极与栅极之间的电压 V2sg为： V2sg=Vs-Vg= Vs-Vp4
=VDD-[ VDD- ( VGH-VGL ) ]
= VGH-VGL
相应的， 此时通过感应线 Lsense的感应电流 Ise大小为：
Ise=Ka(Vsg- IVthal)2: Ka(V2sg- IVthal)2
= Ka[(VGH-VGL) -IVthal]2
综上， 当有触摸动作发生时， 由于耦合电容 Cf的分压作用， 引^文大薄 膜晶体管 ATFT的源极与栅极之间的电压变小， 放大薄膜晶体管 ATFT的放 大能力减弱，从而使得有触摸动作发生时的感应电流 Ise较没有触摸动作发生 时的感应电流 Ise小， 因此，该电路中通过感应电流即可判断该处是否有触控 动作发生。
本发明实施例还提供了一种显示面板， 所述显示面板包括上述的有源矩 阵有机发光二极管 AMOLED像素单元电路。
综上所述， 本发明实施例提供的有源矩阵 AMOLED像素单元电路包括 驱动模块和感应模块； 所述驱动模块中设置有驱动薄膜晶体管、 第一开关元 件、 第一电容、 第二开关元件和驱动控制单元， 通过所述驱动控制单元对第 一电容的充放电， 在清除原来数据电压的同时将匹配薄膜晶体管的阈值电压 和新的数据电压写入第一电容中从而补偿驱动薄膜晶体管的阈值电压， 使得 用于驱动发光二极管发光的驱动电流不受驱动薄膜晶体管的阈值电压的影 响， 同时， 通过所述驱动控制模块引入参考电压， 消除线路内阻对发光电路 的影响， 使得在该像素电路中， 同一灰阶电压下 AMOLED的驱动电流是一 致的， 采用该电路的显示面板的亮度不会有差异， 从而提高了显示面板亮度 的均一性。 更进一步的， 本发明还将触控模块集成在该电路中， 复用了驱动 模块中电源正电压 VDD以及本行像素的和下一行像素的扫描信号 G ( n )、 G ( n+1 ), 用于通过控制感应模块中的第二电容充放电， 以便于手指的触控信 号能被放大晶体管放大， 在不增加电路结构和操作复杂性的同时， 很好的实 现了显示面板的触控功能。 此外， 该电路中采用单一的 P型薄膜晶体管， 从 而降低了制作工艺的复杂程度和成本。
需指出的是， 尽管上述实施例中， 以单一采用 P型薄膜晶体管为例进行 了说明， 然而， 上述电路还可以轻易的改成采用单一的 N型薄膜晶体管或 CMOS管电路； 此外， 还可以将触控功能部分去掉， 将该驱动触控电路改为 纯粹的像素发光驱动电路。 而且， 尽管上述实施例中以有源矩阵有机发光二 极管为例进行了说明， 然而本发明不限于使用有源矩阵有机发光二极管的显 示装置， 也可以应用于使用其他各种发光二极管的显示装置。 发明的精神和范围。 这样， 倘若本发明的这些修改和变型属于本发明权利要 求及其等同技术的范围之内， 则本发明也意图包含这些改动和变型在内。

Claims

权 利 要 求 书
1、一种发光二极管像素单元电路，所述电路包括驱动模块和发光二极管， 其中， 所述驱动模块包括： 驱动薄膜晶体管、 第一开关元件、 第二开关元件、 第一电容和驱动控制单元； 其中，
所述驱动薄膜晶体管的栅极连接第一节点，源极连接电源正电压输出端， 漏极连接所述发光二级管的阳极；
所述发光二级管的阴极连接电源负电压输出端；
所述第一电容位于第一节点与作为驱动控制单元的第一连接端的第二节 点之间；
所述第一开关元件串联在作为驱动控制单元的第二连接端的第三节点和 数据线之间；
所述第二开关元件串联在电源正电压输出端和第一节点之间；
所述驱动控制单元包括阈值电压与驱动薄膜晶体管的阈值电压相匹配的 匹配薄膜晶体管， 位于第一开关元件和第一电容之间， 用于通过控制所述第 一电容充放电， 在清除第一电容中原来数据电压的同时将所述匹配薄膜晶体 管的阈值电压和新的数据电压写入第一电容中， 从而补偿所述驱动薄膜晶体 管的阈值电压。
2、 如权利要求 1所述的电路， 其中， 所述驱动控制单元还包括第三开关 元件和第五开关元件； 其中，
所述第三开关元件串联在第三节点和第二节点之间；
所述匹配薄膜晶体管充当第四开关元件， 与第三开关元件反向并联， 共 同设置在第三节点和第二节点之间；
所述第五开关元件串联在第二节点和参考电压输出端之间。
3、 如权利要求 2所述的电路， 其中， 所述电路还包括感应模块， 所述感 应模块包括第六开关元件、 第七开关元件、 第二电容、 放大薄膜晶体管和感 应元件； 其中，
所述第六开关元件串联在第一节点和放大薄膜晶体管的栅极之间； 所述第七开关元件串联在放大薄膜晶体管的漏极和感应线之间； 所述第二电容串联在放大薄膜晶体管的栅极与第七开关元件的控制端之 间；
所述感应元件连接所述放大薄膜晶体管的栅极；
所述感应模块复用驱动模块中的电源正电压以及扫描信号， 用于通过控 制感应模块中的第二电容充放电 , 使得手指的触控信号被感应模块中的放大 薄膜晶体管放大。
4、 如权利要求 3所述的电路， 其中， 所述第一至第七开关元件分别为第 一至第七薄膜晶体管。
5、 如权利要求 4所述的电路， 其中，
所述第一薄膜晶体管的栅极与本行像素的扫描信号连接， 源极与数据线 连接， 漏极与第三节点连接；
所述第二薄膜晶体管的栅极与本行像素的扫描信号连接， 源极与电源正 电压输出端连接， 漏极与第一节点连接；
所述第三薄膜晶体管的栅极与漏极同时连接第二节点， 源极与第三节点 连接；
所述第四薄膜晶体管的栅极与漏极同时连接第三节点， 源极与第二节点 连接；
所述第五薄膜晶体管的栅极连接本行像素的控制信号， 源极连接第二节 点， 漏极连接参考电压输出端。
6、 如权利要求 4所述的电路， 其中，
所述第六薄膜晶体管的栅极连接本行像素的扫描信号， 源极连接第一节 点， 漏极连接放大薄膜晶体管的栅极；
所述第七薄膜晶体管的栅极连接下一行像素的扫描信号， 源极连接放大 薄膜晶体管的漏极， 漏极连接感应线；
所述放大薄膜晶体管的栅极连接第六薄膜晶体管的漏极， 源极连接电源 正电压， 漏极连接第七薄膜晶体管的源极。
7、 如权利要求 1~6任一所述的电路， 其中， 所有薄膜晶体管均为 P型薄 膜晶体管。
8、 如权利要求 3所述的电路， 其中， 所述感应元件为感应电极， 用于当 人触摸该感应电极时， 与人体之间形成感应电容。
9、如权利要求 4所述的电路， 其中， 所述第四薄膜晶体管与所述驱动薄 膜晶体管的尺寸和形状相同。
10、 一种显示面板， 其特征在于， 所述显示面板包括权利要求 1~9任- 项所述的发光二极管像素单元电路。
PCT/CN2013/080848 2013-05-29 2013-08-05 发光二极管像素单元电路和显示面板 WO2014190614A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US14/371,510 US9318540B2 (en) 2013-05-29 2013-08-05 Light emitting diode pixel unit circuit and display panel

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201310206508.2 2013-05-29
CN201310206508.2A CN103310729B (zh) 2013-05-29 2013-05-29 发光二极管像素单元电路和显示面板

Publications (1)

Publication Number Publication Date
WO2014190614A1 true WO2014190614A1 (zh) 2014-12-04

Family

ID=49135890

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2013/080848 WO2014190614A1 (zh) 2013-05-29 2013-08-05 发光二极管像素单元电路和显示面板

Country Status (3)

Country Link
US (1) US9318540B2 (zh)
CN (1) CN103310729B (zh)
WO (1) WO2014190614A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111162107A (zh) * 2020-01-02 2020-05-15 京东方科技集团股份有限公司 阵列基板、显示面板及显示装置

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103310728B (zh) 2013-05-29 2015-05-20 京东方科技集团股份有限公司 发光二极管像素单元电路和显示面板
CN104103239B (zh) 2014-06-23 2016-05-04 京东方科技集团股份有限公司 有机发光二极管像素电路及其驱动方法
CN104282265B (zh) 2014-09-26 2017-02-01 京东方科技集团股份有限公司 像素电路及其驱动方法、有机发光显示面板及显示装置
CN104778923B (zh) * 2015-04-28 2016-06-01 京东方科技集团股份有限公司 一种像素电路及其驱动方法、显示装置
CN104835449B (zh) * 2015-05-04 2017-05-17 京东方科技集团股份有限公司 像素电路及其驱动方法、阵列基板以及显示装置
CN105702214B (zh) * 2016-04-12 2018-03-06 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
CN106057128B (zh) * 2016-08-24 2018-07-06 中国科学院上海高等研究院 一种电压编程型amoled像素电路及其驱动方法
CN106782426B (zh) * 2017-03-31 2019-06-25 深圳市华星光电半导体显示技术有限公司 驱动电路及液晶显示设备
CN108877649B (zh) * 2017-05-12 2020-07-24 京东方科技集团股份有限公司 像素电路及其驱动方法、显示面板
KR101832831B1 (ko) * 2017-06-14 2018-02-28 주식회사 에이코닉 표시 장치
CN107134259B (zh) * 2017-06-28 2019-04-30 京东方科技集团股份有限公司 像素电路、驱动方法、显示模组、驱动方法和显示装置
KR102387793B1 (ko) * 2017-09-13 2022-04-15 엘지디스플레이 주식회사 터치 센서 일체형 표시장치와 그 구동 방법
US10423286B1 (en) * 2018-03-09 2019-09-24 Int Tech Co., Ltd. Circuit for fingerprint sensing and electronic device comprising the circuit
TWI717963B (zh) * 2019-12-31 2021-02-01 敦泰電子股份有限公司 發光二極體像素顯示單元、發光二極體顯示裝置及其亮度調整方法
CN113129807B (zh) * 2019-12-31 2022-10-14 敦泰电子股份有限公司 发光二极管像素显示单元、发光二极管显示设备及其亮度调整方法
KR20220104412A (ko) 2021-01-18 2022-07-26 삼성전자주식회사 발광 소자 및 이를 포함하는 표시 장치
CN112947790B (zh) * 2021-03-04 2022-06-14 深圳市汇顶科技股份有限公司 触控驱动电路、驱动芯片以及触控显示装置
WO2022183442A1 (zh) 2021-03-04 2022-09-09 深圳市汇顶科技股份有限公司 触控驱动电路、驱动芯片以及触控显示装置
TWI779651B (zh) * 2021-06-08 2022-10-01 友達光電股份有限公司 驅動電路
CN114038393B (zh) * 2021-07-16 2022-10-21 重庆康佳光电技术研究院有限公司 一种像素电路和显示面板
CN114999380A (zh) * 2022-07-07 2022-09-02 武汉华星光电半导体显示技术有限公司 驱动电路、驱动方法及显示面板

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1510652A (zh) * 2002-09-25 2004-07-07 三星电子株式会社 有机发光显示装置及其制造方法
US20050052377A1 (en) * 2003-09-08 2005-03-10 Wei-Chieh Hsueh Pixel driving circuit and method for use in active matrix OLED with threshold voltage compensation
CN1922470A (zh) * 2004-02-24 2007-02-28 彩光公司 用于平板显示器的光笔和触摸屏数据输入系统和方法
CN102708792A (zh) * 2012-02-21 2012-10-03 京东方科技集团股份有限公司 一种像素单元驱动电路和方法、像素单元以及显示装置
WO2013066017A1 (en) * 2011-10-30 2013-05-10 Yong Man Lee Display and touch panels with drive and sense techniques

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW536689B (en) * 2001-01-18 2003-06-11 Sharp Kk Display, portable device, and substrate
GB0401035D0 (en) * 2004-01-17 2004-02-18 Koninkl Philips Electronics Nv Active matrix display devices
US7652291B2 (en) * 2005-05-28 2010-01-26 Samsung Mobile Display Co., Ltd. Flat panel display
US8159422B2 (en) * 2006-09-05 2012-04-17 Canon Kabushiki Kaisha Light emitting display device with first and second transistor films and capacitor with large capacitance value

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1510652A (zh) * 2002-09-25 2004-07-07 三星电子株式会社 有机发光显示装置及其制造方法
US20050052377A1 (en) * 2003-09-08 2005-03-10 Wei-Chieh Hsueh Pixel driving circuit and method for use in active matrix OLED with threshold voltage compensation
CN1922470A (zh) * 2004-02-24 2007-02-28 彩光公司 用于平板显示器的光笔和触摸屏数据输入系统和方法
WO2013066017A1 (en) * 2011-10-30 2013-05-10 Yong Man Lee Display and touch panels with drive and sense techniques
CN102708792A (zh) * 2012-02-21 2012-10-03 京东方科技集团股份有限公司 一种像素单元驱动电路和方法、像素单元以及显示装置

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111162107A (zh) * 2020-01-02 2020-05-15 京东方科技集团股份有限公司 阵列基板、显示面板及显示装置

Also Published As

Publication number Publication date
US9318540B2 (en) 2016-04-19
US20150053947A1 (en) 2015-02-26
CN103310729A (zh) 2013-09-18
CN103310729B (zh) 2015-05-27

Similar Documents

Publication Publication Date Title
WO2014190614A1 (zh) 发光二极管像素单元电路和显示面板
CN103310728B (zh) 发光二极管像素单元电路和显示面板
WO2020062802A1 (zh) 显示面板及像素电路的驱动方法
EP2854124B1 (en) Organic light emitting display device
WO2018054350A1 (zh) 像素电路及其驱动方法、阵列基板以及显示装置
JP6084616B2 (ja) Ｏｌｅｄ画素構造及び駆動方法
WO2016070570A1 (zh) 像素电路、显示基板和显示面板
TWI442374B (zh) 有機發光二極體補償電路
US8605077B2 (en) Display device
WO2020062676A1 (zh) 像素驱动电路和显示装置
CN103198794B (zh) 像素电路及其驱动方法、有机发光显示面板及显示装置
WO2016155053A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2016011711A1 (zh) 像素电路、像素电路的驱动方法和显示装置
WO2015196700A1 (zh) 有机发光二极管像素电路及其驱动方法
WO2015180419A1 (zh) 像素电路及其驱动方法和一种显示装置
WO2018032899A1 (zh) 像素电路及其驱动方法、显示面板和显示装置
US20140055325A1 (en) Pixel unit driving circuit and method thereof, pixel unit and display apparatus
WO2016023311A1 (zh) 像素驱动电路及其驱动方法和显示装置
WO2016119305A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2018157443A1 (zh) 像素补偿电路及驱动方法、显示装置
CN104637446B (zh) 像素电路及其驱动方法和一种显示装置
WO2015003434A1 (zh) 发光二极管像素单元电路、其驱动方法及显示面板
CN103400548A (zh) 像素驱动电路及其驱动方法、显示装置
WO2016078282A1 (zh) 像素单元驱动电路和方法、像素单元和显示装置
WO2020062813A1 (zh) 像素电路、其驱动方法及显示装置

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 14371510

Country of ref document: US

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13885899

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS (EPO FORM 1205A DATED 04.04.2016)

122 Ep: pct application non-entry in european phase

Ref document number: 13885899

Country of ref document: EP

Kind code of ref document: A1