CN101404139A - 电流源装置 - Google Patents

电流源装置 Download PDF

Info

Publication number
CN101404139A
CN101404139A CNA2008101320406A CN200810132040A CN101404139A CN 101404139 A CN101404139 A CN 101404139A CN A2008101320406 A CNA2008101320406 A CN A2008101320406A CN 200810132040 A CN200810132040 A CN 200810132040A CN 101404139 A CN101404139 A CN 101404139A
Authority
CN
China
Prior art keywords
current
mentioned
fet
current output
switch
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.)
Granted
Application number
CNA2008101320406A
Other languages
English (en)
Other versions
CN101404139B (zh
Inventor
内田浩文
本田隆
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.)
Lapis Semiconductor Co Ltd
Original Assignee
Oki Electric Industry 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 Oki Electric Industry Co Ltd filed Critical Oki Electric Industry Co Ltd
Publication of CN101404139A publication Critical patent/CN101404139A/zh
Application granted granted Critical
Publication of CN101404139B publication Critical patent/CN101404139B/zh
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20Control 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
    • G09G3/22Control 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
    • G09G3/32Control 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]
    • G09G3/3208Control 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]
    • G09G3/3216Control 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 a passive matrix
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20Control 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
    • G09G3/22Control 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
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20Control 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
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20Control 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
    • G09G3/22Control 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
    • G09G3/32Control 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]
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20Control 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
    • G09G3/22Control 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
    • G09G3/32Control 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]
    • G09G3/3208Control 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]
    • G09G3/3275Details of drivers for data electrodes
    • G09G3/3283Details of drivers for data electrodes in which the data driver supplies a variable data current for setting the current through, or the voltage across, the light-emitting elements
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11CSTATIC STORES
    • G11C5/00Details of stores covered by group G11C11/00
    • G11C5/14Power supply arrangements, e.g. power down, chip selection or deselection, layout of wirings or power grids, or multiple supply levels
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00Command of the display device
    • G09G2310/02Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0264Details of driving circuits
    • G09G2310/0272Details of drivers for data electrodes, the drivers communicating data to the pixels by means of a current
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00Command of the display device
    • G09G2310/02Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0264Details of driving circuits
    • G09G2310/0275Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00Command of the display device
    • G09G2310/02Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0264Details of driving circuits
    • G09G2310/0291Details of output amplifiers or buffers arranged for use in a driving circuit
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00Control of display operating conditions
    • G09G2320/02Improving the quality of display appearance
    • G09G2320/0223Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes

Landscapes

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

Abstract

本发明提供一种电流源装置,其具有多个可个别地进行输出电流导通截止控制的电流输出电路,能够防止同时切换多个电流输出电路的输出时所产生的误动作。本发明的电流源装置包括多个电流输出电路、和向电流输出FET的各个栅极供给共同的栅极电压的栅极电压供给电路,该多个电流输出电路分别具有:电流输出FET;第1和第2开关FET,其分别串联连接到电流输出FET的源极侧和漏极侧而形成串联电路;电源电压供给单元,其向第1开关FET施加电源电压的正侧电位、并向第2开关FET施加电源电压的负侧电位,向串联电路供给电源电压;以及输出端子,其连接在电流输出FET与第2开关FET之间;该电流输出电路,分别在电流输出FET与第2开关FET之间设置了第3开关FET。

Description

电流源装置
技术领域
本发明涉及电流源装置,该电流源装置使用在半导体集成电路等中,特别适合在将多个发光元件配置成矩阵状而构成的图像显示装置中、向该各个发光元件供给发光驱动电流。
背景技术
图1是表示使用了普通有机电致发光元件(以下称为有机EL元件)的图像显示装置的概略结构的方框图。如该图所示,在显示面板4上形成有n条数据线A1~An和与其交叉配置的m条扫描线B1~Bm,在数据线和扫描线的各个交叉部形成有承担像素的有机EL元件E1~Emn。即,利用形成在显示面板上的m×n个有机EL像素的发光来构成要显示的图像。
扫描线B1~Bm与包含扫描线开关SWB1~SWBm的扫描线驱动部2连接,通过这些扫描线开关的开关动作,向各个扫描线施加接地电位或规定的正电位VH(例如10V)。各个扫描线开关SWB1~SWBm根据由控制部1供给的控制信号,依次向扫描线施加接地电位。即,以一定的时间间隔依次向各个扫描线施加接地电位,并把此期间作为扫描线的选择期间。
另一方面,数据线A1~An与数据线驱动部3连接,该数据线驱动部3包括生成要供给给各个数据线的驱动电流的电流源J1~Jn、和数据线开关SWA1~SWAn,通过该数据线开关的开关动作,使各个数据线与电流源J1~Jn或接地电位中的任意一个连接。各个数据线开关SWA1~SWAn根据由控制部1供给的控制信号,与扫描线的选择期间同步地,选择性地将数据线A1~An与电流源连接。由扫描线开关选择的扫描线上的有机EL元件中的、利用数据线开关与电流源连接的有机EL元件,从电流源接收发光驱动电流,并以和该发光驱动电流对应的亮度进行发光。
例如,在图1中,扫描线B1由扫描线开关SWB1连接到接地电位从而被选择,数据线A2和A3由数据线开关SWA2、SWA3分别连接到电流源J2和J3。由此,设在扫描线B1和数据线A2和A3的各个交叉部的有机EL元件E1,2和E1,3,分别被从电流源J2和J3供给发光驱动电流,以和该发光驱动电流对应的亮度进行发光。在规定的帧期间内依次选择全部的扫描线B1~Bm,并与此同步地向有机EL元件供给与亮度对应的发光驱动电流,通过发光来构成1个画面。
图2是在上述的图像显示装置中,构成通过数据线A1~Am向各个有机EL元件供给发光驱动电流的电流源J1~Jn的电流源装置的等效电路图。电流源装置由单一的栅极电压供给部10、和输出部20构成,该输出部20由分别与各个数据线A1~An对应的n个电流输出电路30-1~30-n构成。
栅极电压供给部10由运算放大器OP1、PMOS晶体管P1及P2、和电阻R1构成。向运算放大器OP1的反相输入端子供给规定的基准电压V1,运算放大器OP1的输出与PMOS晶体管P2的栅极连接。PMOS晶体管P2的源极与PMOS晶体管P1的漏极连接,漏极与一端被固定在规定的负电位Vss的电阻R1连接。向运算放大器OP1的非反相输入端子供给PMOS晶体管P2与电阻R1的连接点的电位。将PMOS晶体管P1的栅极固定在负电位Vss,向源极施加电源电压Vdd。在上述结构的栅极电压供给部10中,利用运算放大器OP1的输出控制PMOS晶体管P2的栅极电压,从而在经由PMOS晶体管P1、P2以及电阻R1的电流路径中流过基于基准电压V1的基准电流I1。另外,PMOS晶体管P1虽然通常保持导通状态,但由于具有规定的导通电阻,所以起到电阻元件的作用。
输出部20如上述那样,由与各个数据线A1~An对应的n个电流输出电路30-1~30-n构成,各个电流输出电路30-1~30-n分别具有相同的结构。在各个电流输出电路中,PMOS晶体管P4,其栅极与PMOS晶体管P2的栅极线,即运算放大器OP1的输出线连接,起生成要供给给数据线的输出电流的电流输出FET的功能。即,在各个电流输出电路中,向PMOS晶体管P4的栅极供给共同的栅极电压。PMOS晶体管P4的漏极与NMOS晶体管N1的漏极连接,源极与PMOS晶体管P3的漏极连接。将NMOS晶体管N1的源极固定在负电位Vss,由控制部1向栅极供给控制信号NSW。在PMOS晶体管P4与NMOS晶体管N1的连接点处设有输出端子OUT1~OUTn,输出端子OUT1~OUTn分别与数据线A1~An连接。向PMOS晶体管P3的源极施加电源电压Vdd,由控制部1向栅极供给控制信号PSW。在上述结构的电流源装置中,将PMOS晶体管P2和P4、PMOS晶体管P1和P3的尺寸(栅极宽度和栅极长度之比W/L)设定为相同,从而可从各个输出端子OUT1~OUTn获得表示与基准电流I1相同电流值的输出电流,并且能向各个数据线A1~An均匀地供给发光驱动电流。
PMOS晶体管P3和NMOS晶体管N1相当于切换是否向数据线供给输出电流的数据线开关SWA1~SWAn。当向PMOS晶体管P3的栅极供给Low电平的控制信号、并向NMOS晶体管N1的栅极供给Low电平的控制信号时,PMOS晶体管P3成为导通状态,NMOS晶体管N1成为截止状态。由此,输出端子的电位成为High电平,向数据线供给发光驱动电流。另一方面,当向PMOS晶体管P3的栅极供给High电平的控制信号、并向NMOS晶体管N1的栅极供给High电平的控制信号时,PMOS晶体管P3成为截止状态,NMOS晶体管N1成为导通状态。由此,输出端子的电位成为Low电平,向数据线的电流供给被停止。即,PMOS晶体管P3和NMOS晶体管N1构成隔着起电流输出FET的作用的PMOS晶体管P4而分别与电源和负电位连接的正侧(高电位侧)开关和负侧(低电位侧)开关。而且,通过切换这些正侧和负侧开关对数据线的电流供给的导通截止,形成开关电流路径。在每个电流输出电路30-1~30-n中进行上述电流源装置的输出电流的导通截止的控制,对每条数据线进行发光驱动电流的供给和停止供给的控制。
具有上述结构的使用在有机EL图像显示装置中的电流源装置,例如记载在专利文献1中。
专利文献:日本特开2003-131617号公报
图3表示在上述以往结构的电流源装置中,从全部电流源电路30-1~30-n向各个数据线供给输出电流的状态,转到继续第n个电流输出电路30-n中的输出电流的供给、而除此以外的第1个到第n-1个电流输出电路中停止电流供给的状态时的各部分的动作波形。在上述的情况下,在第1到第n-1电流输出电路中,在对各个数据线停止电流供给的时刻,控制信号PSW和NSW都被从Low电平切换成High电平。另一方面,在要维持电流供给的第n电流输出电路30-n中,控制信号PSW和NSW被维持在Low电平。另外,由控制部1基于图像数据进行上述控制信号PSW和NSW的输入控制。
这里,在各个电流输出电路30-1~30-n的PMOS晶体管P4的各个栅极-漏极之间存在寄生电容C1,从运算放大器OP1的输出看到的合成电容为n×C1。即,可视为在运算放大器OP1的输出线上连接了大容量的电容。在这种情况下,在第1到第n-1电流输出电路的各个NMOS晶体管N1,根据控制信号NSW的切换而同时成为导通状态时,同时向上述各个寄生电容C1流入充电电流。越是在短时间内产生对上述寄生电容C1的充电,充电电流的瞬时值就越大,运算放大器OP1的驱动能力降低,如图3所示,运算放大器OP1输出线的电位,在充电期间发生暂时下降。在运算放大器OP1输出线的电位发生暂时下降时,在要继续进行电流供给的电流输出电路30-n中,被控制要输出规定的恒定电流的PMOS晶体管P4的栅极电压下降,所以发生输出电流上升且超过规定的控制值的误动作。其结果是,产生了暂时向与数据线An连接的有机EL元件供给因误动作而增加的发光驱动电流,从而影响发光亮度的问题。
发明内容
本发明就是鉴于上述的问题而做出的,其目的是提供一种具有多个可个别地进行输出电流的导通截止控制的电流输出电路的电流源装置,其能够防止因同时切换多个电流输出电路的输出而产生的误动作。
本发明的电流源装置包括多个电流输出电路和栅极电压供给电路,该多个电流输出电路分别具有:电流输出FET;第1和第2开关FET,其分别串联连接到上述电流输出FET的源极侧和漏极侧,形成串联电路;电源电压供给单元,其向上述第1开关FET施加电源电压的正侧电位、并向上述第2开关FET施加上述电源电压的负侧电位,向上述串联电路供给上述电源电压;以及输出端子,其连接在上述电流输出FET与上述第2开关FET之间;该栅极电压供给电路向上述电流输出FET的各个栅极供给共同的栅极电压,其特征在于,上述电流输出电路的还分别具有设置在上述电流输出FET和上述第2开关FET之间的第3开关FET。
根据本发明的电流源装置,在具有多个可分别地进行输出电流的导通截止控制的电流输出电路的电流源装置中,能够防止在同时切换多个电流输出电路的输出时产生的误动作。
附图说明
图1是表示使用了有机EL元件的以往的图像显示装置的整体结构的方框图。
图2是表示以往的电流源装置的结构的等效电路图。
图3是表示以往的电流源装置的动作波形的图。
图4是表示作为本发明的实施例的电流源装置的结构的等效电路图。
图5是表示本发明的电流源装置的动作波形的图。
图6是表示本发明的电流源装置的动作波形的图。
图7是表示作为本发明的其他实施例的电流源装置的结构的等效电路图。
图8是表示作为本发明的其他实施例的电流源装置的动作波形的图。
图9是表示作为本发明的其他实施例的电流源装置的结构的等效电路图。
图10是表示作为本发明的其他实施例的电流源装置的结构的等效电路图。
符号说明
40:栅极电压供给部;50:输出部;60-1~60-n:电流输出电路;70-1~70-n:电流输出电路;80-1~80-n:电流输出电路;OP1:运算放大器;P1~P11:PMOS晶体管;N1~N12:NMOS晶体管。
具体实施方式
下面,参照附图,对本发明的实施例进行说明。另外,在以下所示的图中,对于实质相同或等效的构成要素和部分,赋予同一参照符号。
(第1实施例)
图4是表示本发明的第1实施例的电流源装置100的结构的等效电路图。并且,在图4中,对于与在图2中所示的以往的电流源装置的结构相同的部分标记同一符号。本发明的电流源装置100与以往的结构相同,由单一的栅极电压供给部40、和由分别与数据线A1~An对应的n各电流输出电路60-1~60-n构成的输出部50构成。
栅极电压供给部40与上述以往结构的不同点是,在电阻R1与PMOS晶体管P2之间设有PMOS晶体管P10。即,PMOS晶体管P10的源极与PMOS晶体管P2的漏极连接,漏极与电阻R1连接,栅极被固定在负侧电位Vss。运算放大器OP1的非反相输入端子与PMOS晶体管P10和电阻R1的连接点连接。在上述结构中,虽然PMOS晶体管P10通常为导通状态,但由于具有规定的导通电阻,所以起到电阻元件的作用。PMOS晶体管P10之所以被配置在上述部位,是与在后述的各个电流输出电路60-1~60-n中、相对以往的结构追加了PMOS晶体管P11的情况相对应,使各个电流输出电路中产生与基准电流11相同电流值的镜像电流的缘故。
在各个电流输出电路60-1~60-n中,PMOS晶体管P3(第1开关FET)被串联连接在起电流输出FET作用的PMOS晶体管P4的源极侧,NMOS晶体管N1(第2开关FET)通过后述的PMOS晶体管P11(第3开关FET)连接在PMOS晶体管P4的漏极侧。即,由PMOS晶体管P3、P4、P11、和NMOS晶体管N1构成串联电路。上述串联电路的两端被施加电源电压Vdd。PMOS晶体管P3和NMOS晶体管N1构成隔着PMOS晶体管P4、并分别构成与电源电压的正侧电位连接的正侧(高电位侧)开关及与负侧电位连接的负侧(低电位侧)开关。PMOS晶体管P11被插入PMOS晶体管P4与NMOS晶体管N1之间。具体而言,PMOS晶体管P11的源极与PMOS晶体管P4的漏极连接,漏极与NMOS晶体管N1的漏极连接,栅极由控制部1供给控制信号。PMOS晶体管P11与NMOS晶体管N1的连接点被作为各个电流输出电路的输出端子,各个输出端子与对应的数据线A1~An连接。另外,关于上述以外的构成部分,由于与以往结构的电流源装置相同,所以省略说明。
下面,参照图5所示的各部分的动作波形,对本发明的电流源装置100的动作进行说明。图5与图3所示的情况相同,表示在从全部电流源电路60-1~60-n向各个数据线供给输出电流的状态,转到继续第n个电流输出电路60-n中的输出电流供给,而停止除此以外的第1到第n-1电流输出电路中的电流供给的状态时的各部分的动作波形。在这种情况下,在第1到第n-1电流输出电路中,在停止电流供给的时刻,控制信号PSW和NSW都被从Low电平切换成High电平。另一方面,在要维持电流供给的第n电流输出电路30-n中,控制信号PSW和NSW被维持在Low电平。另外,由控制部1根据图像数据进行上述控制信号PSW和NSW的输入控制。
在各个电流输出电路60-1~60-n中,在控制信号PSW和NSW都被设为Low电平的期间内,PMOS晶体管P3和P11为导通状态,NMOS晶体管N1为截止状态。此时,各个电流输出电路60-1~60-n的输出端子为High电平,向全部数据线A1~An供给输出电流。
在第1到第n-1电流输出电路中,通过把控制信号PSW和NSW都从Low电平切换成High电平,使PMOS晶体管P3和P11成为截止状态,使NMOS晶体管N1成为导通状态。通过使PMOS晶体管P3和P11成为截止状态,来停止输出电流的供给,由于NMOS晶体管N1为导通状态,输出端子的电位为Low电平。这里,在以往的电流源装置中,由于NMOS晶体管N1与PMOS晶体管P4串联连接,所以由于NMOS晶体管N1被驱动为导通状态,所以同时向第1到第n-1电流输出电路的PMOS晶体管P4中附带的各个寄生电容C1流入充电电流,由于运算放大器OP1的驱动能力也有限,所以发生了运算放大器OP1的输出线的电位瞬间下降的不良现象。与此相对,在本发明的电流源装置100中,在PMOS晶体管P4与NMOS晶体管N1之间插入PMOS晶体管P11,在NMOS晶体管N1成为导通状态的时刻,将PMOS晶体管P11置为截止状态,从而将PMOS晶体管P4与NMOS晶体管N1电分离。由此,即使NMOS晶体管N1成为导通状态,PMOS晶体管P4的漏极(图中的节点1)的电位也维持在High电平,所以不产生对寄生电容C1的充电,从而可消除运算放大器OP1的输出线的电位变动。因此,也不产生要维持电流供给的电流输出电路60-n的输出电流的变动,能够对数据线An进行稳定的发光驱动电流的供给。另外,在第1到第n-1电流输出电路中,即可以使控制信号PSW和控制信号NSW同时从Low电平向High电平迁移,也可以使控制信号PSW先迁移到High电平,在使PMOS晶体管P3和P11成为截止状态之后,使控制信号NSW迁移到High电平,使NMOS晶体管N1成为导通状态。
(第2实施例)
在第1实施例所示的电流源装置100中,如上所述,能够消除在将第1到第n-1电流输出电路从电流供给状态转到电流供给停止状态时所产生的不良现象。但是,在将处于电流供给停止状态的第1到第n-1电流输出电路再次同时转到电流供给状态时,有可能产生新的不良现象。下面,参照图6来说明该新的不良现象。另外,关于第n电流输出电路,设为继续进行电流供给。
在第1到第n-1的电流输出电路中,在开始电流供给的时刻,控制信号PSW和NSW都被从High电平切换成Low电平。另一方面,在要维持电流供给的第n电流输出电路60-n中,控制信号PSW和NSW被维持在Low电平。在第1到第n-1电流输出电路中,通过把控制信号PSW和NSW都从High电平切换到Low电平,PMOS晶体管P3和P11成为导通状态,NMOS晶体管N1成为截止状态。由此,向与各个电流输出电路对应的数据线A1~An供给输出电流,输出端子的电位成为High电平。这里,在第1到第n-1的电流输出电路中,在PMOS晶体管P11导通的瞬间,PMOS晶体管P4的漏极(图中的节点1)的电位暂时下降。当由于该节点1的电位变动而向寄生电容C1流入充电电流时,运算放大器OP1的输出线的电位下降。于是,在要继续进行电流供给的电流输出电路60-n中,被控制应输出规定的恒定电流的PMOS晶体管P4的栅极电压下降,所以,与上述的情况相同,产生输出电流上升并超过规定的控制值的误动作。
在第2实施例的电流源装置中,能够消除上述的不良现象。图7表示本发明的第2实施例的电流源装置200。本实施例的电流源装置200在第1实施例的电流源装置100的结构的基础上,分别在电流输出电路60-1~60-n中,设有电位固定用的NMOS晶体管N11。即,分别在本实施例的电流输出电路70-1~70-n中,NMOS晶体管N11的漏极与图中的节点1、即PMOS晶体管P4的漏极连接,源极与负侧电位Vss连接,栅极由控制部1供给控制信号NSW1。NMOS晶体管N11,通过把其尺寸(栅极宽度和栅极长度之比W/L)设为充分小,而使开关速度充分低于NMOS晶体管N1的晶体管。除了追加有NMOS晶体管N11这一点以外,与第1实施例的电流源装置100的结构相同。
下面,参照图8所示的各部分的动作波形,对具有这样结构的电流源装置200的动作进行说明。图8与图6所示的情况相同,表示继续进行第n电流输出电路70-n中的输出电流的供给、并使其他的第1到第n-1电流输出电路从电流供给停止状态转到电流供给状态时的各部的动作波形。此时,在第1到第n-1的电流输出电路中,在开始电流供给的时刻,控制信号PSW和NSW都被从High电平切换到Low电平。另一方面,在要维持电流供给的第n电流输出电路70-n中,控制信号PSW和NSW被维持在Low电平。在这些电流输出电路开始电流供给之前的期间内,即在控制信号PSW和NSW被从High电平切换到Low之前的时间内,对第1到第n-1电流输出电路的NMOS晶体管N11的栅极供给High电平的控制信号NSW1。由此,NMOS晶体管N11成为导通状态,节点1的电位下降,但由于如上述那样NMOS晶体管的开关速度与NMOS晶体管N1的速度相比充分低,所以节点1的电位缓慢下降。其结果是,由于向寄生电容C1的充电也是缓慢发生,所以,运算放大器OP1的输出线的电压下降被运算放大器OP1的驱动能力所抵消。即,通过降低NMOS晶体管N11的开关速度,避免了因NMOS晶体管N11的导通驱动而产生的运算放大器OP1的输出线的电位变动。通过把NMOS晶体管N11驱动为导通状态,把节点1的电位固定为Low电平。而且,在第1到第n-1电流输出电路中,在把节点1的电位固定在Low电位后,将控制信号PSW、NSW和NSW1同时从High电平切换到Low电平。由此,PMOS晶体管P3和P11成为导通状态,NMOS晶体管N1和N11成为截止状态,即使从节点1的电平为Low电平的状态变为PMOS晶体管P11导通状态,也不会引起节点1的瞬间的电位下降,所以不会发生对寄生电容C1的充电,也不会发生运算放大器OP1的输出线的电压变动。因此,在要维持电流供给的第n电流输出电路中,在其他电流输出电路的输出切换的之前到之后,能够向数据线供给稳定的输出电流。
这样,根据第2实施例的电流源电路,在多个电流输出电路从电流供给状态转到电流供给停止状态、并在除此以外的电流输出电路中维持电流供给的动作模式,和在多个电流输出电路从电流供给停止状态转到电流供给状态、并在除此以外的电流输出电路中维持电流供给的动作模式的两种模式中,可防止在该多个电流输出电路的输出切换时刻在要维持电流供给的电流输出电路中产生的输出电流的变动。因此,通过把本发明的电流源装置作为电流源使用,不管动作模式如何,都能向有机EL元件供给稳定的发光驱动电流,可实现发光亮度的稳定化,上述电流源通过与各个电流输出电路对应的多条数据线向分别与该数据线的连接的各个有机EL元件供给发光驱动电流。
(第3实施例)
图9表示本发明的第3实施例的电流源装置300的等效电路图。本实施例的电流源装置300的基本结构与第2实施例相同,但电流输出电路80-1~80-n的结构与第2实施例有若干不同。即,在本实施例的电流输出电路80-1~80-n中,相对于第2实施例的电流输出电路,进一步追加了NMOS晶体管N12。具体而言,NMOS晶体管N12的漏极与PMOS晶体管P4的漏极即节点1连接,源极与NMOS晶体管N11的漏极连接,栅极由外部供给栅极偏压Bias1。栅极偏压Bias1被设定为比NMOS晶体管N12的阈值电压略高的电位。由此,NMOS晶体管N12虽然成为导通状态,但具有与栅极偏压Bias1相应的导通电阻。即,NMOS晶体管N12起到和NMOS晶体管N11串联连接的电阻元件的作用。
本实施例的电流源装置300的动作与上述第2实施例相同,但通过追加NMOS晶体管N12,并使其起电阻元件的作用,进一步降低了NMOS晶体管N11被导通驱动时的电荷流出速度。因此,可进一步降低节点1的电位下降速度,可加强抑制NMOS晶体管N11被导通驱动时向寄生电容C1的瞬间充电的效果。即,根据本实施例的电流源装置,可以使抑制NMOS晶体管N11被导通驱动时的运算放大器OP1的输出线的电位变动的效果更为显著。
另外,替代NMOS晶体管N12而使用电阻,也可以获得同样的效果。另外,对NMOS晶体管N12和N11的配置进行替换,也可以获得同样的效果。再有,即使NMOS晶体管N11的电荷流出部位在PMOS晶体管P3与P4的连接点(即,PMOS晶体管P4的源极),也可以获得同样的效果。而且,在上述各个实施例中,使用开关速度慢的NMOS晶体管N11来使节点1的电荷缓慢地流出,但只要构成限制节点1的电荷流出速度即限制流出电流的机构即可,也可以使用PMOS和DMOS等其他种类的元件。另外,还可以如图10所示,把NMOS晶体管N11的源极与输出端子连接。即使在这样的连接形态下,由于NMOS晶体管N11被导通驱动时输出端子为Low电平,所以在动作上没有问题。

Claims (5)

1.一种电流源装置,包括多个电流输出电路、和栅极电压供给电路,该多个电流输出电路分别具有:电流输出FET;第1和第2开关FET,其分别串联连接到上述电流输出FET的源极侧和漏极侧而形成串联电路;电源电压供给单元,其向上述第1开关FET施加电源电压的正侧电位、并向上述第2开关FET施加上述电源电压的负侧电位,向上述串联电路供给上述电源电压;以及输出端子,其连接在上述电流输出FET与上述第2开关FET之间;
该栅极电压供给电路向上述电流输出FET的各个栅极供给共同的栅极电压;
其特征在于,
各个上述电流输出电路还具有设置在上述电流输出FET与上述第2开关FET之间的第3开关FET。
2.根据权利要求1所述的电流源装置,其特征在于,
各个上述电流输出电路还具有与由上述第2和第3开关FET构成的串联电路并联连接的电位固定FET。
3.根据权利要求2所述的电流源装置,其特征在于,
上述电位固定FET,开关时间比上述第2开关FET慢。
4.根据权利要求3所述的电流源装置,其特征在于,
还具有与上述电位固定FET串联连接的电阻元件。
5.根据权利要求1至4中任意一项所述的电流源装置,其特征在于,
上述第1和第3开关FET是PMOS晶体管,上述第2开关FET是NMOS晶体管。
CN2008101320406A 2007-10-04 2008-07-18 电流源装置 Expired - Fee Related CN101404139B (zh)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2007260811A JP4439552B2 (ja) 2007-10-04 2007-10-04 電流源装置
JP2007-260811 2007-10-04
JP2007260811 2007-10-04

Publications (2)

Publication Number Publication Date
CN101404139A true CN101404139A (zh) 2009-04-08
CN101404139B CN101404139B (zh) 2013-01-23

Family

ID=40522734

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2008101320406A Expired - Fee Related CN101404139B (zh) 2007-10-04 2008-07-18 电流源装置

Country Status (4)

Country Link
US (1) US7863970B2 (zh)
JP (1) JP4439552B2 (zh)
KR (1) KR101519437B1 (zh)
CN (1) CN101404139B (zh)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE502006003275D1 (de) * 2006-09-22 2009-05-07 Siemens Ag Erhöhung der Verfügbarkeit und Redundanz von Analogstromausgaben
JP4717091B2 (ja) 2008-02-29 2011-07-06 Okiセミコンダクタ株式会社 表示パネル駆動装置
JP6117399B2 (ja) * 2016-04-21 2017-04-19 ラピスセミコンダクタ株式会社 定電流出力ドライバ及びこれを含む半導体装置
US11108323B2 (en) * 2017-11-06 2021-08-31 Sony Semiconductor Solutions Corporation Voltage conversion circuit, solid-state imaging element, and method of controlling voltage conversion circuit

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3742230B2 (ja) * 1998-08-28 2006-02-01 株式会社東芝 電流発生回路
JP2001056669A (ja) 1999-01-29 2001-02-27 Seiko Instruments Inc 定電流出力用ドライバ
JP3859483B2 (ja) 2001-10-26 2006-12-20 沖電気工業株式会社 駆動回路
JP3887229B2 (ja) * 2001-12-28 2007-02-28 沖電気工業株式会社 電流駆動型表示装置の駆動回路
US7180513B2 (en) * 2002-04-26 2007-02-20 Toshiba Matsushita Display Technology Co., Ltd. Semiconductor circuits for driving current-driven display and display
JP4059712B2 (ja) * 2002-06-11 2008-03-12 沖電気工業株式会社 表示素子用電流出力回路部の制御回路
JP4743685B2 (ja) * 2005-01-06 2011-08-10 東北パイオニア株式会社 発光表示パネルの駆動装置および駆動方法
JP2007187714A (ja) 2006-01-11 2007-07-26 Matsushita Electric Ind Co Ltd 電流駆動装置
JP2007240698A (ja) * 2006-03-07 2007-09-20 Oki Electric Ind Co Ltd 電流駆動回路

Also Published As

Publication number Publication date
CN101404139B (zh) 2013-01-23
KR101519437B1 (ko) 2015-05-12
US7863970B2 (en) 2011-01-04
JP2009092744A (ja) 2009-04-30
KR20090034717A (ko) 2009-04-08
JP4439552B2 (ja) 2010-03-24
US20090091359A1 (en) 2009-04-09

Similar Documents

Publication Publication Date Title
CN100405441C (zh) 像素电路、显示装置以及像素电路的驱动方法
CN100405438C (zh) 自发光型显示装置
CN101842829B (zh) 图像显示装置以及其控制方法
CN102439652B (zh) 有机电致发光显示装置及其控制方法
CN100511366C (zh) 具有矩阵型电流负载驱动电路的半导体器件及其驱动方法
CN101465597B (zh) 为晶体管驱动器电路提供电压供给的电路装置
US6714177B1 (en) Light-emitting display device and driving method therefor
US20110080432A1 (en) Light emitting element drive circuit
CN100399397C (zh) 抑制显示不匀的图像显示装置
CN103080996B (zh) 显示装置的驱动方法
US20140118413A1 (en) Dc-dc converter and organic light emitting display device using the same
CN102124573A (zh) 面状照明装置和具备它的显示装置
CN104753349A (zh) 电源装置和包括该电源装置的显示设备
US7012587B2 (en) Matrix display device, matrix display driving method, and matrix display driver circuit
CN101404139B (zh) 电流源装置
CN103098236A (zh) 照明装置用集成电路以及照明装置
CN101326563A (zh) 发光显示器以及用于控制所述发光显示器的方法
JPH0869577A (ja) 駆動制御装置
CN114708819A (zh) 一种驱动电路、发光面板以及显示装置
US11475829B2 (en) Optoelectronic light emitting device with a PWM transistor and method for manufacturing or controlling an optoelectronic light emitting device
CN116449088A (zh) 一种实现输入电压快速跳变的瞬态测试电路
CN211606089U (zh) 负载切换保护电路
CN100378783C (zh) D/a转换器电路、有机el驱动电路及有机el显示设备
CN115148162B (zh) 驱动电路、背光电路及显示面板
CN112785970B (zh) 像素驱动电路

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
ASS Succession or assignment of patent right

Owner name: OKI SEMICONDUCTOR CO., LTD.

Free format text: FORMER OWNER: OKI ELECTRIC INDUSTRY CO., LTD.

Effective date: 20131111

C41 Transfer of patent application or patent right or utility model
C56 Change in the name or address of the patentee
CP01 Change in the name or title of a patent holder

Address after: Kanagawa

Patentee after: LAPIS SEMICONDUCTOR Co.,Ltd.

Address before: Kanagawa

Patentee before: Oki Semiconductor Co.,Ltd.

TR01 Transfer of patent right

Effective date of registration: 20131111

Address after: Kanagawa

Patentee after: Oki Semiconductor Co.,Ltd.

Address before: Tokyo, Japan

Patentee before: Oki Electric Industry Co.,Ltd.

CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20130123

Termination date: 20170718

CF01 Termination of patent right due to non-payment of annual fee