CN106652911B - Oled像素驱动电路及oled显示装置 - Google Patents

Oled像素驱动电路及oled显示装置 Download PDF

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CN106652911B
CN106652911B CN201710104522.XA CN201710104522A CN106652911B CN 106652911 B CN106652911 B CN 106652911B CN 201710104522 A CN201710104522 A CN 201710104522A CN 106652911 B CN106652911 B CN 106652911B
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CN106652911A (zh
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邝继木
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Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
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Priority to US15/519,837 priority patent/US10147356B2/en
Priority to PCT/CN2017/076778 priority patent/WO2018152893A1/zh
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    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
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    • G09G3/22Control 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
    • G09G3/30Control 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
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    • G09G3/3208Control 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]
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Abstract

本发明提供一种OLED像素驱动电路及OLED显示装置。该OLED像素驱动电路在2T1C结构的基础上增加第三薄膜晶体管(T3)并设置切换开关(K),切换开关(K)的第一引脚(K1)电性连接第三薄膜晶体管(T3)的漏极,第二引脚(K2)电性连接数模转换器(DAC),第三引脚(K3)电性连接模数转换器(ADC),通过切换信号(Switch)控制切换开关(K)接通第一引脚(K1)与第二引脚(K2)进入显示模式,通过切换信号(Switch)控制切换开关(K)接通第一引脚(K1)与第三引脚(K3)进入感测模式,使得模数转换器(ADC)感测到第二薄膜晶体管(T2)的阈值电压(Vth),经模数转换后用于显示模式下的数据补偿,不仅具有补偿功能,还能够提高像素的开口率,降低制造成本。

Description

OLED像素驱动电路及OLED显示装置
技术领域
本发明涉及显示技术领域,尤其涉及一种OLED像素驱动电路及OLED显示装置。
背景技术
有机发光二极管(Organic Light Emitting Display,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是电流驱动器件,当有电流流经有机发光二极管时,有机发光二极管发光,且发光亮度由流经有机发光二极管自身的电流决定。大部分已有的集成电路(IntegratedCircuit,IC)都只传输电压信号,故OLED的像素驱动电路需要完成将电压信号转变为电流信号的任务。传统的OLED像素驱动电路通常为2T1C,即两个薄膜晶体管加一个电容的结构,将电压变换为电流。
如图1所示,传统的用于OLED的2T1C像素驱动电路包括:第一薄膜晶体管T10、第二薄膜晶体管T20、及电容C10,所述第一薄膜晶体管T10为开关薄膜晶体管,所述第二薄膜晶体管T20为驱动薄膜晶体管,所述电容C10为存储电容。具体地,第一薄膜晶体管T10的栅极接入扫描信号Scan,漏极接入数据信号Data,源极与第二薄膜晶体管T20的栅极、及电容C10的一端电性连接;所述第二薄膜晶体管T20的漏极接入电源电压OVDD,源极电性连接有机发光二极管D10的阳极;有机发光二极管D10的阴极接入公共接地电压OVSS;电容C10的一端电性连接第二薄膜晶体管T20的栅极,另一端电性连接第二薄膜晶体管T20的源极。OLED显示时,扫描信号Scan控制第一薄膜晶体管T10导通,数据信号Data经过第一薄膜晶体管T10进入到第二薄膜晶体管T20的栅极及电容C10,然后第一薄膜晶体管T10截止,由于电容C10的存储作用,第二薄膜晶体管T20的栅极电压仍可继续保持数据信号电压,使得第二薄膜晶体管T20处于导通状态,驱动电流通过第二薄膜晶体管T20进入有机发光二极管D10,驱动有机发光二极管D10发光。
根据计算流经驱动薄膜晶体管及有机发光二极管电流的公式:
IOLED=K×(Vgs-Vth)2
其中:IOLED代表流经驱动薄膜晶体管及有机发光二极管的电流,K为驱动薄膜晶体管的本征导电因子,Vgs代表驱动薄膜晶体管的栅极与源极之间的电压差,Vth代表驱动薄膜晶体管的阈值电压。可见,IOLED的大小与驱动薄膜晶体管的阈值电压Vth有关。
上述传统的OLED像素驱动电路的结构较简单,不具有补偿功能,所以存在很多缺陷,其中比较明显的是:由于薄膜晶体管制造过程中的非均一性,OLED显示装置内每个像素的驱动薄膜晶体管的阈值电压不一致;又因为长时间工作会使驱动薄膜晶体管的材料老化,导致驱动薄膜晶体管的阈值电压漂移,会造成显示不均匀的现象。
图2所示为现有的一种具有补偿功能的3T1C结构的OLED像素驱动电路,在图1所示传统的OLED像素驱动电路的基础上增加了第三薄膜晶体管T30,该第三薄膜晶体管T30的栅极接入感测控制信号Sense,源极电性连接第二薄膜晶体管T20的源极,漏极电性连接模数转换器ADC并接入参考电压信号Vref,数据信号Data由数模转换器DAC提供。该3T1C结构的OLED像素驱动电路能感测到驱动薄膜晶体管的阈值电压Vth,并把Vth值补偿至数据信号Data中,这样能消除驱动薄膜晶体管的阈值电压Vth对流经有机发光二极管的电流IOLED的影响,从而使显示均匀,提高图像质量。但是该3T1C结构的OLED像素驱动电路的缺点有:
1、参考电压信号Vref为各像素提供参考电压,其走线致使像素的开口率降低。
2、参考电压信号Vref的产生使驱动IC的通道数量增加,制造成本增加。
发明内容
本发明的目的在于提供一种OLED像素驱动电路,不仅具有补偿功能,能够消除驱动薄膜晶体管的阈值电压对流经有机发光二极管的电流的影响,提高显示均匀性,还能够提高像素的开口率,降低制造成本。
本发明的另一目的在于提供一种OLED显示装置,其像素驱动电路具有补偿功能,显示均匀性较好,像素开口率较高,制造成本较低。
为实现上述目的,本发明首先提供一种OLED像素驱动电路,包括第一薄膜晶体管、第二薄膜晶体管、第三薄膜晶体管、电容、有机发光二极管、以及设置在驱动IC内的切换开关、数模转换器、与模数转换器;该OLED像素驱动电路的工作状态包括显示模式和感测模式;
所述切换开关受切换信号控制,包括第一引脚、第二引脚、及第三引脚;
所述第一薄膜晶体管的栅极接入扫描信号,漏极接入电源电压,源极与第二薄膜晶体管的栅极、及电容的一端电性连接;所述第二薄膜晶体管的漏极接入电源电压,源极电性连接有机发光二极管的阳极;有机发光二极管的阴极接入公共接地电压;电容的另一端电性连接第二薄膜晶体管的源极;第三薄膜晶体管的栅极在显示模式下接入扫描信号、在感测模式下接入感测控制信号,源极电性连接第二薄膜晶体管的源极,漏极电性连接切换开关的第一引脚;
切换开关的第二引脚电性连接数模转换器,第三引脚电性连接模数转换器;
在显示模式下,切换信号控制切换开关接通第一引脚与第二引脚,数模转换器提供数据信号;在感测模式下,数模转换器先提供一低电位信号,然后切换信号控制切换开关接通第一引脚与第三引脚,使得模数转换器感测到第二薄膜晶体管的阈值电压。
所述数据信号的电位不高于有机发光二极管的阈值电压,所述电源电压高于有机发光二极管的阈值电压与第二薄膜晶体管的阈值电压之和。
所述有机发光二极管的阈值电压为10V。
在显示模式下:所述扫描信号先提供一高电位脉冲,再保持低电位;所述公共接地电压始终为低电位;所述数据信号自扫描信号的高电位脉冲的上升沿开始持续为高电位;
在感测模式下:所述扫描信号先提供一高电位脉冲,再保持低电位;所述感测控制信号先提供一与扫描信号的高电位脉冲同步的高电位脉冲,再保持低电位。
在感测模式下:所述公共接地电压先提供一与感测控制信号的高电位脉冲同步的高电位脉冲,再保持低电位。
本发明还提供一种OLED显示装置,包括OLED像素驱动电路,所述OLED像素驱动电路包括第一薄膜晶体管、第二薄膜晶体管、第三薄膜晶体管、电容、有机发光二极管、以及设置在驱动IC内的切换开关、数模转换器、与模数转换器;该OLED像素驱动电路的工作状态包括显示模式和感测模式;
所述切换开关受切换信号控制,包括第一引脚、第二引脚、及第三引脚;
所述第一薄膜晶体管的栅极接入扫描信号,漏极接入电源电压,源极与第二薄膜晶体管的栅极、及电容的一端电性连接;所述第二薄膜晶体管的漏极接入电源电压,源极电性连接有机发光二极管的阳极;有机发光二极管的阴极接入公共接地电压;电容的另一端电性连接第二薄膜晶体管的源极;第三薄膜晶体管的栅极在显示模式下接入扫描信号、在感测模式下接入感测控制信号,源极电性连接第二薄膜晶体管的源极,漏极电性连接切换开关的第一引脚;
切换开关的第二引脚电性连接数模转换器,第三引脚电性连接模数转换器;
在显示模式下,切换信号控制切换开关接通第一引脚与第二引脚,数模转换器提供数据信号;在感测模式下,数模转换器先提供一低电位信号,然后切换信号控制切换开关接通第一引脚与第三引脚,使得模数转换器感测到第二薄膜晶体管的阈值电压。
所述数据信号的电位不高于有机发光二极管的阈值电压,所述电源电压高于有机发光二极管的阈值电压与第二薄膜晶体管的阈值电压之和。
所述有机发光二极管的阈值电压为10V。
在显示模式下:所述扫描信号先提供一高电位脉冲,再保持低电位;所述公共接地电压始终为低电位;所述数据信号自扫描信号的高电位脉冲的上升沿开始持续为高电位;
在感测模式下:所述扫描信号先提供一高电位脉冲,再保持低电位;所述感测控制信号先提供一与扫描信号的高电位脉冲同步的高电位脉冲,再保持低电位。
在感测模式下:所述公共接地电压先提供一与感测控制信号的高电位脉冲同步的高电位脉冲,再保持低电位。
本发明的有益效果:本发明提供的一种OLED像素驱动电路及OLED显示装置,在2T1C结构的基础上增加第三薄膜晶体管并设置切换开关,切换开关的第一引脚电性连接第三薄膜晶体管的漏极,第二引脚电性连接数模转换器,第三引脚电性连接模数转换器,通过切换信号控制切换开关接通第一引脚与第二引脚进入显示模式,通过切换信号控制切换开关接通第一引脚与第三引脚进入感测模式,使得模数转换器感测到第二薄膜晶体管的阈值电压,经模数转换后用于显示模式下的数据补偿,从而具有补偿功能,能够消除驱动薄膜晶体管的阈值电压对流经有机发光二极管的电流的影响,提高显示均匀性,并且无需像现有技术那样额外设置参考电压信号,从而还能够提高像素的开口率,降低制造成本。
附图说明
为了能更进一步了解本发明的特征以及技术内容,请参阅以下有关本发明的详细说明与附图,然而附图仅提供参考与说明用,并非用来对本发明加以限制。
附图中,
图1为传统的用于OLED的2T1C像素驱动电路的电路图;
图2为现有的一种具有补偿功能的3T1C结构的OLED像素驱动电路的电路图;
图3为本发明的OLED像素驱动电路的电路图;
图4为本发明的OLED像素驱动电路在显示模式下的电路连接图;
图5为本发明的OLED像素驱动电路在显示模式下的时序图;
图6为本发明的OLED像素驱动电路在感测模式下的电路连接图;
图7为本发明的OLED像素驱动电路在感测模式下的时序图。
具体实施方式
为更进一步阐述本发明所采取的技术手段及其效果,以下结合本发明的优选实施例及其附图进行详细描述。
请同时参阅图3至图7,本发明提供一种OLED像素驱动电路。如图3、图4、及图6所示,本发明的OLED像素驱动电路包括第一薄膜晶体管T1、第二薄膜晶体管T2、第三薄膜晶体管T3、电容C1、有机发光二极管D1、以及设置在驱动IC 10内的切换开关K、数模转换器DAC、与模数转换器ADC。其中,所述第二薄膜晶体管T2为直接对有机发光二极管D1进行驱动的驱动薄膜晶体管。
该OLED像素驱动电路在2T1C结构的基础上增加了第三薄膜晶体管T3并设置切换开关K,且其工作状态包括显示模式和感测模式。
具体地:所述切换开关K受切换信号Switch控制,包括第一引脚K1、第二引脚K2、及第三引脚K3;
所述第一薄膜晶体管T1的栅极接入扫描信号Scan,漏极接入电源电压OVDD,源极与第二薄膜晶体管T2的栅极、及电容C1的一端电性连接;所述第二薄膜晶体管T2的漏极接入电源电压OVDD,源极电性连接有机发光二极管D1的阳极;有机发光二极管D1的阴极接入公共接地电压OVSS;电容C1的另一端电性连接第二薄膜晶体管T2的源极;第三薄膜晶体管T3的栅极在显示模式下接入扫描信号Scan、在感测模式下接入感测控制信号Sense,源极电性连接第二薄膜晶体管T2的源极,漏极电性连接切换开关K的第一引脚K1;
切换开关K的第二引脚K2电性连接数模转换器DAC,第三引脚K3电性连接模数转换器ADC。
所述第一薄膜晶体管T1、第二薄膜晶体管T2、与第三薄膜晶体管T3均为低温多晶硅薄膜晶体管、氧化物半导体薄膜晶体管、或非晶硅薄膜晶体管。
结合图4与图5,在显示模式下:所述切换信号Switch控制切换开关K接通第一引脚K1与第二引脚K2,数模转换器DAC提供数据信号Data。所述扫描信号Scan先提供一高电位脉冲,使得第一薄膜晶体管T1和第三薄膜晶体管T3均导通。在这一阶段,电源电压OVDD经导通的第一薄膜晶体管T1进入第二薄膜晶体管T2的栅极g,即Vg=OVDD(Vg表示第二薄膜晶体管T2的栅极g的电位);所述数据信号Data自扫描信号Scan的高电位脉冲的上升沿开始持续为高电位,数据信号Data经切换开关K的第一引脚K1与第二引脚K2、及导通的第三薄膜晶体管T3写入第二薄膜晶体管T2的源极s,即Vs=VData(Vs表示第二薄膜晶体管T2的源极s的电位,VData表示数据信号Data的电位)。之后,扫描信号Scan再保持低电位,使得第一薄膜晶体管T1和第三薄膜晶体管T3均截止,依靠电容C1的存储作用,所述有机发光二极管D1发光进行显示。
值得注意的是:在显示模式下,公共接地电压OVSS始终为低电位;所述数据信号Data的电位VData不高于有机发光二极管D1的阈值电压Vth-OLED,即VData≤Vth-OLED,进一步地,所述有机发光二极管D1的阈值电压Vth-OLED约为10V(针对发光层为三叠层或四叠层的有机发光二极管),这样能够保证在数据信号Data写入过程中第二薄膜晶体管T2的源极s的电位Vs不能使有机发光二极管D1点亮;所述电源电压OVDD高于有机发光二极管D1的阈值电压Vth-OLED与第二薄膜晶体管T2的阈值电压Vth之和,即OVDD>Vth-OLED+Vth,这样在数据信号Data写入完成后,第二薄膜晶体管T2的栅极g与源极s之间的电压Vgs为:
Vgs=Vg-Vs=OVDD-VData>Vth
保证有机发光二极管D1能正常发光、显示。
结合图6与图7,在感测模式下:所述扫描信号Scan先提供一高电位脉冲使得第一薄膜晶体管T1导通,电源电压OVDD经导通的第一薄膜晶体管T1进入第二薄膜晶体管T2的栅极g,即Vg=OVDD;所述感测控制信号Sense先提供一与扫描信号Scan的高电位脉冲同步的高电位脉冲使第三薄膜晶体管T3导通,所述切换信号Switch先保持切换开关K接通第一引脚K1与第二引脚K2,数模转换器DAC先提供一低电位信号经切换开关K的第一引脚K1与第二引脚K2、及导通的第三薄膜晶体管T3写入第二薄膜晶体管T2的源极s,同时,所述公共接地电压OVSS先提供一与感测控制信号Sense的高电位脉冲同步的高电位脉冲,保证有机发光二极管D1不能被点亮。紧接着,切换信号Switch控制切换开关K接通第一引脚K1与第三引脚K3,此时,由于第二薄膜晶体管T2的栅极g的电位为OVDD,而源极s处于较低电位,模数转换器ADC通过导通的第三薄膜晶体管T3、及切换开关K的第一引脚K1与第三引脚K3能够感测到第二薄膜晶体管T2即驱动薄膜晶体管的阈值电压Vth。在这之后,所述扫描信号Scan、感测控制信号Sense、及公共接地电压OVSS均转变为低电位并保持。
模数转换器ADC感测到第二薄膜晶体管T2即驱动薄膜晶体管的阈值电压Vth后转换成数字型的感测数据,并将该数字型的感测数据储存,供显示模式下做数据补偿之用。由于显示模式下,第二薄膜晶体管T2即驱动薄膜晶体管的阈值电压Vth得到补偿,流经有机发光二极管D1的电流便与驱动薄膜晶体管的阈值电压Vth无关,消除了驱动薄膜晶体管的阈值电压Vth对发光二极管D1的影响,能够提高显示的均匀性,提高发光效率,并且本发明的OLED像素驱动电路无需像现有技术那样额外设置参考电压信号,从而省略参考电压信号的走线,减少驱动IC的通道数量,提高像素的开口率,降低制造成本。
基于同一发明构思,本发明还提供一种OLED显示装置,包括上述的OLED像素驱动电路,此处不再对该OLED像素驱动电路的结构及功能进行重复性描述。
综上所述,本发明的OLED像素驱动电路及OLED显示装置,在2T1C结构的基础上增加第三薄膜晶体管并设置切换开关,切换开关的第一引脚电性连接第三薄膜晶体管的漏极,第二引脚电性连接数模转换器,第三引脚电性连接模数转换器,通过切换信号控制切换开关接通第一引脚与第二引脚进入显示模式,通过切换信号控制切换开关接通第一引脚与第三引脚进入感测模式,使得模数转换器感测到第二薄膜晶体管的阈值电压,经模数转换后用于显示模式下的数据补偿,从而具有补偿功能,能够消除驱动薄膜晶体管的阈值电压对流经有机发光二极管的电流的影响,提高显示均匀性,并且无需像现有技术那样额外设置参考电压信号,从而还能够提高像素的开口率,降低制造成本。
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 (8)

1.一种OLED像素驱动电路,其特征在于,包括第一薄膜晶体管(T1)、第二薄膜晶体管(T2)、第三薄膜晶体管(T3)、电容(C1)、有机发光二极管(D1)、以及设置在驱动IC(10)内的切换开关(K)、数模转换器(DAC)、与模数转换器(ADC);该OLED像素驱动电路的工作状态包括显示模式和感测模式;
所述切换开关(K)受切换信号(Switch)控制,包括第一引脚(K1)、第二引脚(K2)、及第三引脚(K3);
所述第一薄膜晶体管(T1)的栅极接入扫描信号(Scan),漏极接入电源电压(OVDD),源极与第二薄膜晶体管(T2)的栅极、及电容(C1)的一端电性连接;所述第二薄膜晶体管(T2)的漏极接入电源电压(OVDD),源极电性连接有机发光二极管(D1)的阳极;有机发光二极管(D1)的阴极接入公共接地电压(OVSS);电容(C1)的另一端电性连接第二薄膜晶体管(T2)的源极;第三薄膜晶体管(T3)的栅极在显示模式下接入扫描信号(Scan)、在感测模式下接入感测控制信号(Sense),源极电性连接第二薄膜晶体管(T2)的源极,漏极电性连接切换开关(K)的第一引脚(K1);
切换开关(K)的第二引脚(K2)电性连接数模转换器(DAC),第三引脚(K3)电性连接模数转换器(ADC);
在显示模式下,切换信号(Switch)控制切换开关(K)接通第一引脚(K1)与第二引脚(K2),数模转换器(DAC)提供数据信号(Data);在感测模式下,数模转换器(DAC)先提供一低电位信号,然后切换信号(Switch)控制切换开关(K)接通第一引脚(K1)与第三引脚(K3),使得模数转换器(ADC)感测到第二薄膜晶体管(T2)的阈值电压(Vth);
所述数据信号(Data)的电位不高于有机发光二极管(D1)的阈值电压,所述电源电压(OVDD)高于有机发光二极管(D1)的阈值电压与第二薄膜晶体管(T2)的阈值电压(Vth)之和。
2.如权利要求1所述的OLED像素驱动电路,其特征在于,所述有机发光二极管(D1)的阈值电压为10V。
3.如权利要求1所述的OLED像素驱动电路,其特征在于,在显示模式下:所述扫描信号(Scan)先提供一高电位脉冲,再保持低电位;所述公共接地电压(OVSS)始终为低电位;所述数据信号(Data)自扫描信号(Scan)的高电位脉冲的上升沿开始持续为高电位;
在感测模式下:所述扫描信号(Scan)先提供一高电位脉冲,再保持低电位;所述感测控制信号(Sense)先提供一与扫描信号(Scan)的高电位脉冲同步的高电位脉冲,再保持低电位。
4.如权利要求3所述的OLED像素驱动电路,其特征在于,在感测模式下:所述公共接地电压(OVSS)先提供一与感测控制信号(Sense)的高电位脉冲同步的高电位脉冲,再保持低电位。
5.一种OLED显示装置,其特征在于,包括OLED像素驱动电路,所述OLED像素驱动电路包括第一薄膜晶体管(T1)、第二薄膜晶体管(T2)、第三薄膜晶体管(T3)、电容(C1)、有机发光二极管(D1)、以及设置在驱动IC(10)内的切换开关(K)、数模转换器(DAC)、与模数转换器(ADC);该OLED像素驱动电路的工作状态包括显示模式和感测模式;
所述切换开关(K)受切换信号(Switch)控制,包括第一引脚(K1)、第二引脚(K2)、及第三引脚(K3);
所述第一薄膜晶体管(T1)的栅极接入扫描信号(Scan),漏极接入电源电压(OVDD),源极与第二薄膜晶体管(T2)的栅极、及电容(C1)的一端电性连接;所述第二薄膜晶体管(T2)的漏极接入电源电压(OVDD),源极电性连接有机发光二极管(D1)的阳极;有机发光二极管(D1)的阴极接入公共接地电压(OVSS);电容(C1)的另一端电性连接第二薄膜晶体管(T2)的源极;第三薄膜晶体管(T3)的栅极在显示模式下接入扫描信号(Scan)、在感测模式下接入感测控制信号(Sense),源极电性连接第二薄膜晶体管(T2)的源极,漏极电性连接切换开关(K)的第一引脚(K1);
切换开关(K)的第二引脚(K2)电性连接数模转换器(DAC),第三引脚(K3)电性连接模数转换器(ADC);
在显示模式下,切换信号(Switch)控制切换开关(K)接通第一引脚(K1)与第二引脚(K2),数模转换器(DAC)提供数据信号(Data);在感测模式下,数模转换器(DAC)先提供一低电位信号,然后切换信号(Switch)控制切换开关(K)接通第一引脚(K1)与第三引脚(K3),使得模数转换器(ADC)感测到第二薄膜晶体管(T2)的阈值电压(Vth);
所述数据信号(Data)的电位不高于有机发光二极管(D1)的阈值电压,所述电源电压(OVDD)高于有机发光二极管(D1)的阈值电压与第二薄膜晶体管(T2)的阈值电压(Vth)之和。
6.如权利要求5所述的OLED显示装置,其特征在于,所述有机发光二极管(D1)的阈值电压为10V。
7.如权利要求5所述的OLED显示装置,其特征在于,在显示模式下:所述扫描信号(Scan)先提供一高电位脉冲,再保持低电位;所述公共接地电压(OVSS)始终为低电位;所述数据信号(Data)自扫描信号(Scan)的高电位脉冲的上升沿开始持续为高电位;
在感测模式下:所述扫描信号(Scan)先提供一高电位脉冲,再保持低电位;所述感测控制信号(Sense)先提供一与扫描信号(Scan)的高电位脉冲同步的高电位脉冲,再保持低电位。
8.如权利要求7所述的OLED显示装置,其特征在于,在感测模式下:所述公共接地电压(OVSS)先提供一与感测控制信号(Sense)的高电位脉冲同步的高电位脉冲,再保持低电位。
CN201710104522.XA 2017-02-24 2017-02-24 Oled像素驱动电路及oled显示装置 Active CN106652911B (zh)

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