[go: up one dir, main page]

WO2019037300A1 - Amoled像素驱动电路 - Google Patents

Amoled像素驱动电路 Download PDF

Info

Publication number
WO2019037300A1
WO2019037300A1 PCT/CN2017/111335 CN2017111335W WO2019037300A1 WO 2019037300 A1 WO2019037300 A1 WO 2019037300A1 CN 2017111335 W CN2017111335 W CN 2017111335W WO 2019037300 A1 WO2019037300 A1 WO 2019037300A1
Authority
WO
WIPO (PCT)
Prior art keywords
thin film
node
film transistor
threshold voltage
potential
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/CN2017/111335
Other languages
English (en)
French (fr)
Inventor
韩佰祥
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Original Assignee
Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
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 Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd filed Critical Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority to US15/580,277 priority Critical patent/US10354592B2/en
Publication of WO2019037300A1 publication Critical patent/WO2019037300A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—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

Definitions

  • the present invention relates to the field of display technologies, and in particular, to an AMOLED pixel driving circuit.
  • the organic light emitting diode (OLED) display device has self-luminous, low driving voltage, high luminous efficiency, short response time, high definition and contrast, near 180° viewing angle, wide temperature range, and flexible display and large-area full-color display. And many other advantages, recognized by the industry as the most promising display device.
  • the OLED display device can be classified into two types: passive matrix OLED (PMOLED) and active matrix OLED (AMOLED) according to the driving method.
  • PMOLED passive matrix OLED
  • AMOLED active matrix OLED
  • the AMOLED has pixels arranged in an array, belongs to an active display type, has high luminous efficiency, and is generally used as a high-definition large-sized display device.
  • AMOLED is a current-driven device. The brightness is determined by the current flowing through the OLED itself. Most existing chips (IC) only transmit voltage signals. Therefore, the AMOLED pixel driving circuit must complete the task of converting the voltage signal into a current signal, usually 2T1C. Voltage/current (V/I) conversion circuit.
  • FIG. 1 it is a schematic diagram of a conventional 2T1C pixel driving circuit, which mainly includes two thin film transistors (TFTs) and a capacitor (C), which converts a voltage into a current to drive an OLED, wherein one thin film transistor is a switching TFT and is scanned by a signal.
  • (Scan) control for controlling the entry of the data signal (Data)
  • the other thin film transistor is a driving TFT for controlling the current through the organic light emitting diode
  • the scanning signal may be from the gate driver
  • the data signal may be from the source driver.
  • the importance of the threshold voltage Vth of the driving TFT is very obvious, and the positive or negative drift of the threshold voltage causes different currents to pass through the organic light emitting diode under the same data signal, which affects the uniformity of the brightness of the entire panel.
  • thin film transistors fabricated from low-temperature polysilicon or oxide semiconductors sometimes exhibit threshold voltage drift during use due to various factors.
  • the simple design of the pixel drive circuit of Figure 1 is sensitive to the threshold voltage and channel mobility of the TFT, the OLED startup voltage and quantum efficiency, and the transient process of the power supply. With this 2T1C pixel circuit without compensation, the luminance unevenness of the AMOLED is about 50% or more.
  • Compensation means that the parameters of the driving TFTs in each pixel (such as threshold voltage and mobility) must be compensated, so that the output current becomes independent of these parameters. .
  • an object of the present invention to provide an AMOLED pixel driving circuit capable of compensating for electrical drift of a driving TFT.
  • an AMOLED pixel driving circuit including:
  • a first thin film transistor as a driving transistor which is a double gate thin film transistor, a top gate is connected to the first node, a bottom gate is connected to the second node, and a source and a drain are respectively connected to the power supply high potential and the third node;
  • a second thin film transistor having a gate connected to the scan line, and a source and a drain connected to the first node and the first data line, respectively;
  • a third thin film transistor having a gate connected to the scan line, and a source and a drain respectively connected to the detection signal line and the third node;
  • a fourth thin film transistor having a gate connected to the scan line, and a source and a drain connected to the second node and the second data line, respectively;
  • the organic light emitting diode has an anode connected to the third node and a cathode connected to the power source at a low potential.
  • the first thin film transistor, the second thin film transistor, the third thin film transistor, and the fourth thin film transistor are low temperature polysilicon thin film transistors or oxide semiconductor thin film transistors.
  • the scan line is set to an input high potential; the first data line is set to input a first reference voltage; and the first thin film transistor is The threshold voltage detection state is divided into an initialization phase and a threshold voltage generation phase according to time, and the detection signal line is set to input a second reference voltage in an initialization phase, and is set to be suspended in a threshold voltage generation phase, and the second reference voltage is less than The first reference voltage is less than the turn-on voltage of the organic light emitting diode; the second data line is set to a third reference voltage.
  • the third reference voltage is 0 volts.
  • the potential of the third node rises to a difference between the first reference voltage and the threshold voltage of the first thin film transistor, and the threshold voltage of the first thin film transistor is obtained by the potential of the third node, and the second node The potential is the third reference voltage.
  • the first thin film transistor threshold voltage of each pixel in the panel is obtained and stored in the memory.
  • the threshold voltage of the first thin film transistor is adjusted to be uniformly set to all the pixels of the panel.
  • the potential of the second node required for the value is based on the obtained potential of the second node to form compensation data to further form a compensation signal based on the compensation data.
  • the compensation signals corresponding to each pixel in the panel are respectively obtained.
  • the threshold voltage compensation and the light emitting state of the first thin film transistor are divided into a compensation phase and an illumination phase according to time, and the scan line is in the compensation phase.
  • the first data line is set as an input data signal;
  • the second data line is set as an input compensation signal;
  • the detection signal line is set as an input a fourth reference voltage, the fourth reference voltage being less than an on voltage of the organic light emitting diode.
  • the invention also provides an AMOLED pixel driving circuit, comprising:
  • a first thin film transistor as a driving transistor which is a double gate thin film transistor, a top gate is connected to the first node, a bottom gate is connected to the second node, and a source and a drain are respectively connected to the power supply high potential and the third node;
  • a second thin film transistor having a gate connected to the scan line, and a source and a drain connected to the first node and the first data line, respectively;
  • a third thin film transistor having a gate connected to the scan line, and a source and a drain respectively connected to the detection signal line and the third node;
  • a fourth thin film transistor having a gate connected to the scan line, and a source and a drain connected to the second node and the second data line, respectively;
  • An organic light emitting diode having an anode connected to a third node and a cathode connected to a low potential
  • the first thin film transistor, the second thin film transistor, the third thin film transistor, and the fourth thin film transistor are low temperature polysilicon thin film transistors or oxide semiconductor thin film transistors;
  • the scan line is set to an input high potential;
  • the first data line is set to input a first reference voltage;
  • the first thin film transistor is The threshold voltage detection state is divided into an initialization phase and a threshold voltage generation phase according to time, and the detection signal line is set to input a second reference voltage in an initialization phase, and is set to be suspended in a threshold voltage generation phase, and the second reference voltage is less than a first reference voltage and less than an on voltage of the organic light emitting diode;
  • the second data line is set to a third reference voltage;
  • the third reference voltage is 0 volts
  • the potential of the third node rises to the first reference power
  • the voltage is different from the threshold voltage of the first thin film transistor, and the threshold voltage of the first thin film transistor is obtained by the potential of the third node, and the potential of the second node is the third reference voltage.
  • the AMOLED pixel driving circuit of the present invention effectively compensates for the electrical drift of the driving TFT.
  • 1 is a schematic diagram of a conventional 2T1C pixel driving circuit
  • FIG. 2 is a schematic diagram of a preferred embodiment of an AMOLED pixel driving circuit of the present invention
  • FIG. 3 is a timing diagram of a preferred embodiment of an AMOLED pixel driving circuit operating in a threshold voltage detection state
  • FIG. 4 is a schematic circuit diagram of a preferred embodiment of an AMOLED pixel driving circuit in a threshold voltage generation phase
  • FIG. 5 is a schematic diagram of a Vth-node B potential corresponding to a preferred embodiment of the AMOLED pixel driving circuit of the present invention
  • FIG. 6 is a schematic diagram showing a threshold voltage compensation and a light-emitting state of a preferred embodiment of the AMOLED pixel driving circuit of the present invention.
  • a preferred embodiment of the AMOLED pixel driving circuit of the present invention mainly includes: a double gate thin film transistor as a driving transistor.
  • T1 the signal of the data line Data1 is supplied to the thin film transistor T2 of the T1 top gate by the signal of the scan line Scan, and the signal of the detection signal line Sense is supplied to the thin film transistor T3 of the T1 source by the signal of the scan line Scan.
  • the signal of the data line Data2 is supplied to the thin film transistor T4, the capacitor C, the capacitor Cst, and the organic light emitting diode D1 of the bottom gate of the T1 by the signal control of the scan line Scan.
  • the top gate of the driving transistor T1 is connected to the node G, the bottom gate is connected to the node B, the source and the drain are respectively connected to the power supply high potential VDD and the node S; the gate of the T2 is connected to the scan line Scan, and the source and the drain are respectively connected to the node G and The data line Data1; T3 gate is connected to the scan line Scan, the source and the drain are respectively connected to the detection signal line Sense and the node S; the T4 gate is connected to the scan line Scan, and the source and the drain are respectively connected to the node B and the data line Data2;
  • the two ends of the capacitor C are respectively connected to the node B and the power supply high potential VDD; the two ends of the capacitor Cst are respectively connected to the node G and the node S; the organic light emitting diode D1 Yang
  • the pole is connected to the node S, and the cathode is connected to the power source VSS.
  • FIG. 3 it is a timing diagram of the preferred embodiment operating in a threshold voltage detection state.
  • the scan line Scan is set to input high potential; the data line Data1 is set to input the first reference voltage Ref1; the T1 threshold voltage detection state is divided into the initialization phase and the threshold voltage generation phase by time, and the detection signal line Sense is detected.
  • the initialization phase it is set to input the second reference voltage Ref2, which is set to be floating in the threshold voltage generation phase, the second reference voltage Ref2 is smaller than the first reference voltage Ref1 and smaller than the turn-on voltage of D1; the second data line Data2 is set to the third reference voltage.
  • Ref3 for convenience, can be 0 volts.
  • scan line Scan is high, then T2, T3, T4 are on; node G is written to Ref1; node S is written to Ref2; and node B is written to Ref3.
  • the detection signal line Sense is set to be floating.
  • the scan line Scan continues to be high, T2, T3, and T4 are still turned on; the peripheral detection circuit or the signal provided by the chip to detect the signal line Sense is set to float.
  • the potential of the node S rises to the difference between the first reference voltage Ref1 and the T1 threshold voltage Vth, which can be expressed as Ref1-Vth_T1, the threshold voltage Vth of T1 is captured to the S point, and the detecting circuit passes through the node.
  • the potential of S and the known Ref1 can obtain the T1 threshold voltage Vth, and the potential of the node B is the third reference voltage Ref3.
  • the threshold voltage of the first thin film transistor T1 of each pixel in the panel can be obtained separately and stored in the memory. According to the threshold voltage detection process of the driving TFT T1 of a single pixel, all the pixels in the panel can be scanned line by line until the Vth of T1 of all the pixels in the panel is detected and stored in the memory.
  • the threshold voltage Vth value of the TFT can be controlled by the bottom gate potential.
  • the node B potential can be controlled.
  • the Vth value of T1 can determine the correspondence between Vth and the potential of the node B according to the actual measurement condition.
  • the node B potential correction value corresponding to the Vth of each pixel T1 is calculated according to the Vth-node B relationship, and the graph is obtained.
  • the Vth-node B potential shown in FIG. 5 corresponds to the schematic diagram, and the corresponding node B potential can pull the Vth of T1 of all the pixels in the panel to the same value, and the same value can be uniformly set by all the pixels of the panel.
  • the node B potential can be written back to the data line Data2 as compensation data during the compensation and illumination phases.
  • the compensation data can be formed according to the potential of the corresponding node B to further form a compensation signal according to the compensation data for providing to T1 for subsequent illumination.
  • the compensation signals corresponding to T1 of each pixel in the panel can be obtained separately for later use.
  • FIG. 6 there is shown a schematic diagram of the preferred embodiment operating in a threshold voltage compensation and illumination state.
  • the T1 threshold voltage compensation and the light-emitting state are divided into the compensation phase and the light-emitting phase by time, the scan line Scan is set to the input high potential in the compensation phase, and the input low potential is set in the illumination phase; the data line Data1 is set as the input data.
  • the data line Data2 is set as an input compensation signal;
  • the detection signal line Sense is set to input a fourth reference voltage Ref, and the fourth reference voltage Ref is smaller than the on voltage of D1.
  • the scan line Scan is turned on for the high potential, T2, T3, T4; the node G writes the data signal of the current row and column; the node B writes the compensation signal (can come from the aforementioned threshold)
  • the scan line Scan is turned to a low potential, T2, T3, and T4 are turned off; the nodes G and S are subjected to a coupling potential, and the voltage Vgs across the capacitor Cst is unchanged, and is still a data signal -Ref; D1 starts to emit light, and since the Vth of T1 of each pixel is corrected to the same reference value by the potential of the node B, the luminance of the light is uniform, which compensates well for the Vth variation of T1.
  • the 4T2C pixel driving circuit proposed by the present invention includes, but is not limited to, a low-temperature polysilicon process and an oxide semiconductor process. Any pixel-like design method involved in any possible process belongs to the protection scope of the present invention; the TFT size of the 4T2C pixel driving circuit proposed by the present invention is Capacitance values and timing diagrams allow for a certain degree of flexibility, and any changes based on this are within the scope of protection of the present invention.
  • the AMOLED pixel driving circuit of the present invention effectively compensates for the electrical drift of the driving TFT.

Landscapes

  • 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)

Abstract

本发明涉及一种AMOLED像素驱动电路。该驱动电路包括：第一薄膜晶体管(T1)，顶栅极连接第一节点(G)，底栅极连接第二节点(B)，源极和漏极分别连接电源高电位(VDD)和第三节点(S)；第二薄膜晶体管(T2)，其栅极连接扫描线(Scan)，源极和漏极分别连接第一节点(G)和第一数据线(Data1)；第三薄膜晶体管(T3)，其栅极连接扫描线(Scan)，源极和漏极分别连接侦测信号线(Sense)和第三节点(S)；第四薄膜晶体管(T4)，其栅极连接扫描线(Scan)，源极和漏极分别连接第二节点(B)和第二数据线(Data2)；第一电容(C)，连接第二节点(B)和电源高电位(VDD)；第二电容(Cst)，连接第一节点(G)和第三节点(S)；有机发光二极管(D1)，其阳极连接第三节点(S)。本发明对驱动TFT的电性漂移进行了有效的补偿。

Description

AMOLED像素驱动电路 技术领域
本发明涉及显示技术领域，尤其涉及一种AMOLED像素驱动电路。
背景技术
有机发光二极管(OLED)显示装置具有自发光、驱动电压低、发光效率高、响应时间短、清晰度与对比度高、近180°视角、使用温度范围宽，可实现柔性显示与大面积全色显示等诸多优点，被业界公认为是最有发展潜力的显示装置。OLED显示装置按照驱动方式可以分为无源矩阵型OLED(Passive Matrix OLED，PMOLED)和有源矩阵型OLED(Active Matrix OLED，AMOLED)两大类。其中，AMOLED具有呈阵列式排布的像素，属于主动显示类型，发光效能高，通常用作高清晰度的大尺寸显示装置。
AMOLED是电流驱动器件，亮度由流过OLED自身的电流决定，大部分已有芯片(IC)都只传输电压信号，故AMOLED像素驱动电路要完成将电压信号转变为电流信号的任务，通常为2T1C电压/电流(V/I)变换电路。
参见图1，其为传统2T1C的像素驱动电路示意图，主要包括两个薄膜晶体管(TFT)和一个电容(C)，将电压转换为电流以驱动OLED，其中一个薄膜晶体管为开关TFT，由扫描信号(Scan)控制，用于控制数据信号(Data)的进入，另一个薄膜晶体管为驱动TFT，用于控制通过有机发光二极管的电流，扫描信号可以来自于栅极驱动器，数据信号可以来自于源极驱动器。因此驱动TFT的阈值电压Vth的重要性便十分明显，阈值电压的正向或负向漂移都有会使得在相同数据信号下有不同的电流通过有机发光二极管，影响整个面板亮度的均匀。然而，目前由低温多晶硅或氧化物半导体制作的薄膜晶体管因各种因素在使用过程中均会发生阈值电压漂移现象。
图1这种设计简单的像素驱动电路对TFT的阈值电压和沟道迁移率、OLED启动电压和量子效率以及供电电源的瞬变过程都很敏感。使用这种不带补偿的2T1C像素电路，AMOLED亮度的不均匀性约为50％，或者更大。
解决不均匀性的一个方法是对每一个像素加补偿电路，补偿意味着必须对每一个像素中的驱动TFT的参数(例如阈值电压和迁移率)进行补偿，使输出电流变得与这些参数无关。
发明内容
因此，本发明的目的在于提供一种AMOLED像素驱动电路，能够补偿驱动TFT的电性漂移。
为实现上述目的，本发明提供了一种AMOLED像素驱动电路，包括：
作为驱动晶体管的第一薄膜晶体管，其为双栅极薄膜晶体管，顶栅极连接第一节点，底栅极连接第二节点，源极和漏极分别连接电源高电位和第三节点；
第二薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第一节点和第一数据线；
第三薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接侦测信号线和第三节点；
第四薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第二节点和第二数据线；
第一电容，其两端分别连接第二节点和电源高电位；
第二电容，其两端分别连接第一节点和第三节点；
有机发光二极管，其阳极连接第三节点，阴极连接电源低电位。
其中，所述第一薄膜晶体管、第二薄膜晶体管、第三薄膜晶体管、及第四薄膜晶体管为低温多晶硅薄膜晶体管或者为氧化物半导体薄膜晶体管。
其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压侦测状态时，所述扫描线设置为输入高电位；所述第一数据线设置为输入第一参考电压；将第一薄膜晶体管阈值电压侦测状态按时间划分为初始化阶段和阈值电压生成阶段，所述侦测信号线在初始化阶段设置为输入第二参考电压，在阈值电压生成阶段设置为悬空，所述第二参考电压小于第一参考电压且小于有机发光二极管的开启电压；所述第二数据线设置为第三参考电压。
其中，所述第三参考电压为0伏特。
其中，在阈值电压生成阶段，所述第三节点的电位上升至第一参考电压与第一薄膜晶体管阈值电压之差，通过第三节点的电位得到第一薄膜晶体管阈值电压，此时第二节点的电位为第三参考电压。
其中，对于面板中所有像素，分别得到面板中每个像素的第一薄膜晶体管阈值电压并存储于存储器中。
其中，通过所述第一薄膜晶体管阈值电压与第二节点的电位之间的对应关系，得到欲将第一薄膜晶体管阈值电压调整至面板所有像素统一设定 值时所需的第二节点的电位，根据所得到的第二节点的电位形成补偿数据，以进而根据补偿数据形成补偿信号。
其中，对于面板中所有像素，分别得到面板中每个像素对应的补偿信号。
其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压补偿及发光状态时，将第一薄膜晶体管阈值电压补偿及发光状态按时间划分为补偿阶段和发光阶段，所述扫描线在补偿阶段设置为输入高电位，在发光状阶段设置为输入低电位；所述第一数据线设置为输入数据信号；所述第二数据线设置为输入补偿信号；所述侦测信号线设置为输入第四参考电压，所述第四参考电压小于有机发光二极管的开启电压。
本发明还提供一种AMOLED像素驱动电路，包括：
作为驱动晶体管的第一薄膜晶体管，其为双栅极薄膜晶体管，顶栅极连接第一节点，底栅极连接第二节点，源极和漏极分别连接电源高电位和第三节点；
第二薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第一节点和第一数据线；
第三薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接侦测信号线和第三节点；
第四薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第二节点和第二数据线；
第一电容，其两端分别连接第二节点和电源高电位；
第二电容，其两端分别连接第一节点和第三节点；
有机发光二极管，其阳极连接第三节点，阴极连接电源低电位；
其中，所述第一薄膜晶体管、第二薄膜晶体管、第三薄膜晶体管、及第四薄膜晶体管为低温多晶硅薄膜晶体管或者为氧化物半导体薄膜晶体管；
其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压侦测状态时，所述扫描线设置为输入高电位；所述第一数据线设置为输入第一参考电压；将第一薄膜晶体管阈值电压侦测状态按时间划分为初始化阶段和阈值电压生成阶段，所述侦测信号线在初始化阶段设置为输入第二参考电压，在阈值电压生成阶段设置为悬空，所述第二参考电压小于第一参考电压且小于有机发光二极管的开启电压；所述第二数据线设置为第三参考电压；
其中，所述第三参考电压为0伏特；
其中，在阈值电压生成阶段，所述第三节点的电位上升至第一参考电 压与第一薄膜晶体管阈值电压之差，通过第三节点的电位得到第一薄膜晶体管阈值电压，此时第二节点的电位为第三参考电压。
综上，本发明的AMOLED像素驱动电路对驱动TFT的电性漂移进行了有效的补偿。
附图说明
下面结合附图，通过对本发明的具体实施方式详细描述，将使本发明的技术方案及其他有益效果显而易见。
附图中，
图1为传统2T1C的像素驱动电路示意图；
图2为本发明AMOLED像素驱动电路一较佳实施例的示意图；
图3为本发明AMOLED像素驱动电路一较佳实施例工作于阈值电压侦测状态的时序示意图；
图4为本发明AMOLED像素驱动电路一较佳实施例在阈值电压生成阶段的电路示意图；
图5为本发明AMOLED像素驱动电路一较佳实施例中得到的Vth-节点B电位对应示意图；
图6为本发明AMOLED像素驱动电路一较佳实施例工作于阈值电压补偿及发光状态示意图。
具体实施方式
参见图2，为实现对单像素的补偿及驱动，本发明引入双栅结构调控驱动TFT的阈值电压，本发明AMOLED像素驱动电路一较佳实施例主要包括：作为驱动晶体管的双栅极薄膜晶体管T1、由扫描线Scan的信号控制将数据线Data1的信号提供至T1顶栅极的薄膜晶体管T2、由扫描线Scan的信号控制将侦测信号线Sense的信号提供至T1源极的薄膜晶体管T3、由扫描线Scan的信号控制将数据线Data2的信号提供至T1底栅极的薄膜晶体管T4、电容C、电容Cst以及有机发光二极管D1。
驱动晶体管T1顶栅极连接节点G，底栅极连接节点B，源极和漏极分别连接电源高电位VDD和节点S；T2栅极连接扫描线Scan，源极和漏极分别连接节点G和数据线Data1；T3栅极连接扫描线Scan，源极和漏极分别连接侦测信号线Sense和节点S；T4栅极连接扫描线Scan，源极和漏极分别连接节点B和数据线Data2；电容C两端分别连接节点B和电源高电位VDD；电容Cst两端分别连接节点G和节点S；有机发光二极管D1阳 极连接节点S，阴极连接电源低电位VSS。
参见图3，其为该较佳实施例工作于阈值电压侦测状态的时序示意图。此时，所述扫描线Scan设置为输入高电位；数据线Data1设置为输入第一参考电压Ref1；将T1阈值电压侦测状态按时间划分为初始化阶段和阈值电压生成阶段，侦测信号线Sense在初始化阶段设置为输入第二参考电压Ref2，在阈值电压生成阶段设置为悬空，第二参考电压Ref2小于第一参考电压Ref1且小于D1的开启电压；第二数据线Data2设置为第三参考电压Ref3，为后续方便，可以为0伏特。
在初始化(Initial)阶段，扫描线Scan给高电位，则T2，T3，T4打开；节点G写入Ref1；节点S写入Ref2；节点B写入Ref3。
参见图4，其为该较佳实施例在阈值电压生成阶段的电路示意图，此时侦测信号线Sense设置为悬空。在阈值电压生成(Vth Generation)阶段，扫描线Scan持续高电位，T2，T3，T4仍然打开；将外围的侦测电路或芯片所提供得侦测信号线Sense的信号设置为悬空(floating)，由于受到VDD充电影响，节点S的电位上升至第一参考电压Ref1与T1阈值电压Vth之差，可表示为Ref1－Vth_T1，T1的阈值电压Vth被抓取到S点，侦测电路等通过节点S的电位和已知的Ref1可得到T1阈值电压Vth，此时节点B的电位为第三参考电压Ref3。
对于面板中所有像素，可以分别得到面板中每个像素的第一薄膜晶体管T1阈值电压并存储于存储器中。按照单个像素的驱动TFT T1的阈值电压侦测过程，可以通过对面板中所有像素进行逐行扫描，直到面板中所有像素的T1的Vth被侦测完毕，存储到存储器中。
参见图5，其为该较佳实施例中得到的Vth-B电位对应示意图。根据现有研究表明，对于图2中的双栅极薄膜晶体管T1形式，可以通过底栅极电位来控制TFT的阈值电压Vth值，对于该较佳实施例来说，也就是节点B电位可以控制T1的Vth值，可以根据实际量测条件确定Vth和节点B电位的对应关系。
通过从存储器中读取上一阶段(阈值电压生成阶段)侦测的面板中所有像素T1的Vth值，根据Vth-节点B关系计算每个像素T1的Vth对应的节点B电位矫正值，得到图5所示的Vth-节点B电位对应示意图，相应的节点B电位可以将面板中所有像素的T1的Vth拉到同一值，此同一值可以通过面板所有像素预先统一设定实现。在补偿及发光阶段可以将节点B电位作为补偿数据回写至数据线Data2。根据相应的节点B的电位可以形成补偿数据，以进而根据补偿数据形成补偿信号，用于后续发光时提供给T1。 对于面板中所有像素，可以分别得到面板中每个像素的T1所对应的补偿信号，以备后续使用。
参见图6，其为该较佳实施例工作于阈值电压补偿及发光状态示意图。此时，将T1阈值电压补偿及发光状态按时间划分为补偿阶段和发光阶段，扫描线Scan在补偿阶段设置为输入高电位，在发光状阶段设置为输入低电位；数据线Data1设置为输入数据信号；所述数据线Data2设置为输入补偿信号；侦测信号线Sense设置为输入第四参考电压Ref，第四参考电压Ref小于D1的开启电压。
在补偿阶段，也可以称为编程(Programming)阶段，扫描线Scan给高电位，T2，T3，T4打开；节点G写入当前行列的数据信号；节点B写入补偿信号(可以来自于前述阈值电压侦测状态)并存储在电容C上；节点S写入第四参考电压Ref(＜D1开启电压)；此时存储电容Cst两端电压Vgs＝数据信号－Ref。
在发光(Emitting)阶段，扫描线Scan给低电位，T2，T3，T4关闭；节点G和S受到耦合作用电位升高，此时电容Cst两端电压Vgs不变，仍为数据信号－Ref；D1开始发光，由于每个像素的T1的Vth被节点B电位矫正为同一基准值，所以发光亮度均一，很好的补偿了T1的Vth变异。
本发明提出的4T2C像素驱动电路包含但不局限于低温多晶硅制程、氧化物半导体制程，任何可能的制程涉及的类似像素设计方法均属于本发明保护范畴；本发明提出的4T2C像素驱动电路TFT尺寸、电容值以及时序图允许一定的可变灵活度，任何在此基础上的变化均属于本发明的保护范畴。
综上，本发明的AMOLED像素驱动电路对驱动TFT的电性漂移进行了有效的补偿。
以上所述，对于本领域的普通技术人员来说，可以根据本发明的技术方案和技术构思作出其他各种相应的改变和变形，而所有这些改变和变形都应属于本发明后附的权利要求的保护范围。

Claims (14)

  1. 一种AMOLED像素驱动电路，包括：
    作为驱动晶体管的第一薄膜晶体管，其为双栅极薄膜晶体管，顶栅极连接第一节点，底栅极连接第二节点，源极和漏极分别连接电源高电位和第三节点；
    第二薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第一节点和第一数据线；
    第三薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接侦测信号线和第三节点；
    第四薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第二节点和第二数据线；
    第一电容，其两端分别连接第二节点和电源高电位；
    第二电容，其两端分别连接第一节点和第三节点；
    有机发光二极管，其阳极连接第三节点，阴极连接电源低电位。
  2. 如权利要求1所述的AMOLED像素驱动电路，其中，所述第一薄膜晶体管、第二薄膜晶体管、第三薄膜晶体管、及第四薄膜晶体管为低温多晶硅薄膜晶体管或者为氧化物半导体薄膜晶体管。
  3. 如权利要求1所述的AMOLED像素驱动电路，其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压侦测状态时，所述扫描线设置为输入高电位；所述第一数据线设置为输入第一参考电压；将第一薄膜晶体管阈值电压侦测状态按时间划分为初始化阶段和阈值电压生成阶段，所述侦测信号线在初始化阶段设置为输入第二参考电压，在阈值电压生成阶段设置为悬空，所述第二参考电压小于第一参考电压且小于有机发光二极管的开启电压；所述第二数据线设置为第三参考电压。
  4. 如权利要求3所述的AMOLED像素驱动电路，其中，所述第三参考电压为0伏特。
  5. 如权利要求3所述的AMOLED像素驱动电路，其中，在阈值电压生成阶段，所述第三节点的电位上升至第一参考电压与第一薄膜晶体管阈值电压之差，通过第三节点的电位得到第一薄膜晶体管阈值电压，此时第二节点的电位为第三参考电压。
  6. 如权利要求5所述的AMOLED像素驱动电路，其中，对于面板中所有像素，分别得到面板中每个像素的第一薄膜晶体管阈值电压并存储于 存储器中。
  7. 如权利要求5所述的AMOLED像素驱动电路，其中，通过所述第一薄膜晶体管阈值电压与第二节点的电位之间的对应关系，得到欲将第一薄膜晶体管阈值电压调整至面板所有像素统一设定值时所需的第二节点的电位，根据所得到的第二节点的电位形成补偿数据，以进而根据补偿数据形成补偿信号。
  8. 如权利要求7所述的AMOLED像素驱动电路，其中，对于面板中所有像素，分别得到面板中每个像素对应的补偿信号。
  9. 如权利要求1所述的AMOLED像素驱动电路，其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压补偿及发光状态时，将第一薄膜晶体管阈值电压补偿及发光状态按时间划分为补偿阶段和发光阶段，所述扫描线在补偿阶段设置为输入高电位，在发光状阶段设置为输入低电位；所述第一数据线设置为输入数据信号；所述第二数据线设置为输入补偿信号；所述侦测信号线设置为输入第四参考电压，所述第四参考电压小于有机发光二极管的开启电压。
  10. 一种AMOLED像素驱动电路，包括：
    作为驱动晶体管的第一薄膜晶体管，其为双栅极薄膜晶体管，顶栅极连接第一节点，底栅极连接第二节点，源极和漏极分别连接电源高电位和第三节点；
    第二薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第一节点和第一数据线；
    第三薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接侦测信号线和第三节点；
    第四薄膜晶体管，其栅极连接扫描线，源极和漏极分别连接第二节点和第二数据线；
    第一电容，其两端分别连接第二节点和电源高电位；
    第二电容，其两端分别连接第一节点和第三节点；
    有机发光二极管，其阳极连接第三节点，阴极连接电源低电位；
    其中，所述第一薄膜晶体管、第二薄膜晶体管、第三薄膜晶体管、及第四薄膜晶体管为低温多晶硅薄膜晶体管或者为氧化物半导体薄膜晶体管；
    其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压侦测状态时，所述扫描线设置为输入高电位；所述第一数据线设置为输入第一参考电压；将第一薄膜晶体管阈值电压侦测状态按时间划分为初始化阶段和阈值电压生成阶段，所述侦测信号线在初始化阶段设置为输入第二参 考电压，在阈值电压生成阶段设置为悬空，所述第二参考电压小于第一参考电压且小于有机发光二极管的开启电压；所述第二数据线设置为第三参考电压；
    其中，所述第三参考电压为0伏特；
    其中，在阈值电压生成阶段，所述第三节点的电位上升至第一参考电压与第一薄膜晶体管阈值电压之差，通过第三节点的电位得到第一薄膜晶体管阈值电压，此时第二节点的电位为第三参考电压。
  11. 如权利要求10所述的AMOLED像素驱动电路，其中，对于面板中所有像素，分别得到面板中每个像素的第一薄膜晶体管阈值电压并存储于存储器中。
  12. 如权利要求10所述的AMOLED像素驱动电路，其中，通过所述第一薄膜晶体管阈值电压与第二节点的电位之间的对应关系，得到欲将第一薄膜晶体管阈值电压调整至面板所有像素统一设定值时所需的第二节点的电位，根据所得到的第二节点的电位形成补偿数据，以进而根据补偿数据形成补偿信号。
  13. 如权利要求12所述的AMOLED像素驱动电路，其中，对于面板中所有像素，分别得到面板中每个像素对应的补偿信号。
  14. 如权利要求10所述的AMOLED像素驱动电路，其中，所述AMOLED像素驱动电路工作于第一薄膜晶体管阈值电压补偿及发光状态时，将第一薄膜晶体管阈值电压补偿及发光状态按时间划分为补偿阶段和发光阶段，所述扫描线在补偿阶段设置为输入高电位，在发光状阶段设置为输入低电位；所述第一数据线设置为输入数据信号；所述第二数据线设置为输入补偿信号；所述侦测信号线设置为输入第四参考电压，所述第四参考电压小于有机发光二极管的开启电压。
PCT/CN2017/111335 2017-08-22 2017-11-16 Amoled像素驱动电路 Ceased WO2019037300A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US15/580,277 US10354592B2 (en) 2017-08-22 2017-11-16 AMOLED pixel driver circuit

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201710726140.0 2017-08-22
CN201710726140.0A CN107316614B (zh) 2017-08-22 2017-08-22 Amoled像素驱动电路

Publications (1)

Publication Number Publication Date
WO2019037300A1 true WO2019037300A1 (zh) 2019-02-28

Family

ID=60175941

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/111335 Ceased WO2019037300A1 (zh) 2017-08-22 2017-11-16 Amoled像素驱动电路

Country Status (2)

Country Link
CN (1) CN107316614B (zh)
WO (1) WO2019037300A1 (zh)

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10354592B2 (en) 2017-08-22 2019-07-16 Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd. AMOLED pixel driver circuit
CN107316614B (zh) * 2017-08-22 2019-10-11 深圳市华星光电半导体显示技术有限公司 Amoled像素驱动电路
CN108172171B (zh) * 2017-12-20 2020-01-17 武汉华星光电半导体显示技术有限公司 像素驱动电路及有机发光二极管显示器
CN110021265B (zh) * 2019-04-26 2021-01-12 上海天马微电子有限公司 一种像素电路及其驱动方法、显示装置及驱动方法
CN110189707A (zh) * 2019-05-30 2019-08-30 京东方科技集团股份有限公司 一种像素驱动电路及其驱动方法、显示装置
CN110189698B (zh) * 2019-06-28 2021-04-13 京东方科技集团股份有限公司 像素电路及其驱动方法、显示装置
TWI697884B (zh) 2019-08-20 2020-07-01 友達光電股份有限公司 畫素電路
CN110706650A (zh) * 2019-09-17 2020-01-17 深圳市华星光电半导体显示技术有限公司 像素驱动电路
CN110808010A (zh) * 2019-10-29 2020-02-18 深圳市华星光电半导体显示技术有限公司 像素驱动电路、显示面板、显示装置及像素驱动方法
CN110689837B (zh) * 2019-10-29 2023-11-28 深圳市华星光电半导体显示技术有限公司 像素驱动电路以及显示面板
JP7535848B2 (ja) * 2019-12-13 2024-08-19 エルジー ディスプレイ カンパニー リミテッド 発光表示装置
CN111081190B (zh) * 2019-12-18 2021-08-24 深圳市华星光电半导体显示技术有限公司 Goa电路、显示面板及薄膜晶体管的阈值电压补偿方法
CN111292694B (zh) * 2020-02-18 2021-06-01 深圳市华星光电半导体显示技术有限公司 像素驱动电路及其驱动方法、显示面板
CN111261110A (zh) * 2020-03-09 2020-06-09 深圳市华星光电半导体显示技术有限公司 Amoled像素驱动电路、像素驱动方法及显示面板
US11315516B2 (en) 2020-03-23 2022-04-26 Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd. Method of driving pixel driving circuit solving problems of greater power consumption of blue phase liquid crystal panel
CN111402788A (zh) * 2020-04-08 2020-07-10 深圳市华星光电半导体显示技术有限公司 一种像素电路和显示面板
CN111402816A (zh) * 2020-04-14 2020-07-10 深圳市华星光电半导体显示技术有限公司 一种像素电路和具有该像素电路的amoled显示面板
CN111785212A (zh) * 2020-08-05 2020-10-16 京东方科技集团股份有限公司 一种像素电路、其驱动方法及显示装置
CN112071268B (zh) * 2020-08-12 2022-02-22 武汉华星光电半导体显示技术有限公司 显示面板和显示装置
CN112201201A (zh) * 2020-10-28 2021-01-08 武汉华星光电技术有限公司 显示驱动电路及显示装置
CN112562590A (zh) * 2020-12-30 2021-03-26 深圳市华星光电半导体显示技术有限公司 像素驱动电路及显示装置
CN113053314A (zh) * 2021-03-30 2021-06-29 福建华佳彩有限公司 一种oled面板的补偿电路及其驱动方法
KR20230122344A (ko) * 2022-02-14 2023-08-22 송기석 파도력 발전장치
CN114373414B (zh) * 2022-01-18 2023-06-02 深圳市华星光电半导体显示技术有限公司 显示面板电性的侦测电路以及显示面板
CN115798409B (zh) * 2022-12-23 2025-02-28 深圳市华星光电半导体显示技术有限公司 像素驱动电路及显示面板
KR20240106136A (ko) 2022-12-29 2024-07-08 엘지디스플레이 주식회사 표시 장치

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101667391A (zh) * 2008-09-03 2010-03-10 佳能株式会社 像素电路、发光显示装置及其驱动方法
CN105741779A (zh) * 2016-03-24 2016-07-06 北京大学深圳研究生院 一种基于双栅晶体管的像素电路及其驱动方法
US20160260373A1 (en) * 2015-03-05 2016-09-08 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and method for driving the same
CN106486522A (zh) * 2015-08-26 2017-03-08 乐金显示有限公司 有机发光显示装置及其制造方法
CN106652910A (zh) * 2016-10-31 2017-05-10 昆山工研院新型平板显示技术中心有限公司 像素电路及其驱动方法和有机发光显示器
CN107316614A (zh) * 2017-08-22 2017-11-03 深圳市华星光电半导体显示技术有限公司 Amoled像素驱动电路

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI330726B (en) * 2005-09-05 2010-09-21 Au Optronics Corp Display apparatus, thin-film-transistor discharge method and electrical driving method therefor
KR102122517B1 (ko) * 2012-12-17 2020-06-12 엘지디스플레이 주식회사 유기발광 표시장치
KR102241704B1 (ko) * 2014-08-07 2021-04-20 삼성디스플레이 주식회사 화소 회로 및 이를 포함하는 유기 발광 표시 장치
JP2017010000A (ja) * 2015-04-13 2017-01-12 株式会社半導体エネルギー研究所 表示装置
CN205080864U (zh) * 2015-09-16 2016-03-09 中国科学院物理研究所 薄膜晶体管驱动电路
CN105741781B (zh) * 2016-04-12 2018-10-26 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
CN106504699B (zh) * 2016-10-14 2019-02-01 深圳市华星光电技术有限公司 Amoled像素驱动电路及驱动方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101667391A (zh) * 2008-09-03 2010-03-10 佳能株式会社 像素电路、发光显示装置及其驱动方法
US20160260373A1 (en) * 2015-03-05 2016-09-08 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and method for driving the same
CN106486522A (zh) * 2015-08-26 2017-03-08 乐金显示有限公司 有机发光显示装置及其制造方法
CN105741779A (zh) * 2016-03-24 2016-07-06 北京大学深圳研究生院 一种基于双栅晶体管的像素电路及其驱动方法
CN106652910A (zh) * 2016-10-31 2017-05-10 昆山工研院新型平板显示技术中心有限公司 像素电路及其驱动方法和有机发光显示器
CN107316614A (zh) * 2017-08-22 2017-11-03 深圳市华星光电半导体显示技术有限公司 Amoled像素驱动电路

Also Published As

Publication number Publication date
CN107316614B (zh) 2019-10-11
CN107316614A (zh) 2017-11-03

Similar Documents

Publication Publication Date Title
WO2019037300A1 (zh) Amoled像素驱动电路
US10354592B2 (en) AMOLED pixel driver circuit
KR102176454B1 (ko) Amoled 픽셀 구동 회로 및 구동 방법
US10354590B2 (en) Hybrid compensation circuit and method for OLED pixel
CN107492343B (zh) 用于oled显示设备的像素驱动电路、oled显示设备
US10056037B1 (en) AMOLED pixel driver circuit and pixel driving method
CN104658474B (zh) 有机发光显示器和补偿有机发光显示器的阈值电压的方法
CN105185300B (zh) Amoled像素驱动电路及像素驱动方法
CN106297662B (zh) Amoled像素驱动电路及驱动方法
US10121416B2 (en) AMOLED pixel driver circuit and pixel driving method
WO2016119304A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2019033487A1 (zh) 用于oled显示设备的像素驱动电路及oled显示设备
WO2018045660A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2016145693A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2016155053A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2016155087A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2017156826A1 (zh) Amoled像素驱动电路及像素驱动方法
CN108777131B (zh) Amoled像素驱动电路及驱动方法
WO2018068392A1 (zh) Amoled像素驱动电路及驱动方法
WO2016123855A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2019033516A1 (zh) 用于oled显示设备的像素驱动电路、oled显示设备
WO2016119305A1 (zh) Amoled像素驱动电路及像素驱动方法
WO2018149008A1 (zh) Amoled像素驱动电路及amoled像素驱动方法
US20180102090A1 (en) Amoled pixel driving circuit and pixel driving method
KR102244932B1 (ko) 유기 발광 표시 장치 및 그의 구동 방법

Legal Events

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

Ref document number: 17922272

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17922272

Country of ref document: EP

Kind code of ref document: A1