CN106251808B - A kind of output buffer for AMOLED column drive circuits - Google Patents

A kind of output buffer for AMOLED column drive circuits Download PDF

Info

Publication number
CN106251808B
CN106251808B CN201610719581.3A CN201610719581A CN106251808B CN 106251808 B CN106251808 B CN 106251808B CN 201610719581 A CN201610719581 A CN 201610719581A CN 106251808 B CN106251808 B CN 106251808B
Authority
CN
China
Prior art keywords
transistor
common
grid
output
source electrode
Prior art date
Application number
CN201610719581.3A
Other languages
Chinese (zh)
Other versions
CN106251808A (en
Inventor
汪辉
黄尊恺
田犁
章琦
汪宁
黄景林
曹虎
Original Assignee
中国科学院上海高等研究院
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 中国科学院上海高等研究院 filed Critical 中国科学院上海高等研究院
Priority to CN201610719581.3A priority Critical patent/CN106251808B/en
Publication of CN106251808A publication Critical patent/CN106251808A/en
Application granted granted Critical
Publication of CN106251808B publication Critical patent/CN106251808B/en

Links

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]
    • G09G3/3225Control 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
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K19/00Logic circuits, i.e. having at least two inputs acting on one output; Inverting circuits
    • H03K19/0175Coupling arrangements; Interface arrangements
    • H03K19/0185Coupling arrangements; Interface arrangements using field effect transistors only
    • 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

Abstract

The present invention provides a kind of output buffer for AMOLED column drive circuits, including:Rail-to-rail input stage circuit, bootstrapping grade circuit and output-stage circuit, the rail-to-rail input stage circuit connects the bootstrapping grade circuit, the bootstrapping grade circuit connects the output-stage circuit, and the rail-to-rail input stage is amplified the difference of positive input signal and rp input signal;The bootstrapping grade circuit, rises above supply voltage by the control voltage of output-stage circuit or falls below ground voltage;The output-stage circuit, drives output loading.The present invention is for solving the problem of that output buffer in the prior art needs the factors such as comprehensive area, power consumption to advanced optimize circuit when load capacitance further increases.

Description

A kind of output buffer for AMOLED column drive circuits

Technical field

The present invention relates to flat panel display technology fields, slow more particularly to a kind of output for AMOLED column drive circuits Rush device.

Background technology

AMOLED shows compared with other display technologies there is ultra-thin, wide viewing angle, low-power consumption, fast response time, color The advantages that natural is the most contenders of next-generation mainstream display technology.In AMOLED display system, column drive circuit for Realize that high speed, high-precision, low-power consumption and the display of high dynamic driving are most important.Usual column drive circuit includes shift LD Device, sample register, data latches, level shifting circuit, D/A converting circuit (Digital-to-Analog Converter, DAC) and output buffer circuit etc..Wherein, output buffer determine the speed of column drive circuit, precision, The performances such as output area and power consumption, with the raising of display resolution and frame per second, system wants the performance of output buffer Ask also higher and higher.

Output buffer in AMOLED column drive circuits usually connects into unity gain buffer by operational amplifier Form is realized, for driving in AMOLED display panels capacitance big in row driving bus, with the increase of display display surface battle array, The output buffer capacitance to be driven is also increasing.The output buffer for being traditionally used for AMOLED column drive circuits is AB Class A amplifier A, as shown in Figure 1, the amplifier can provide big gain, to reduce systematic error, while its output stage is to push away Tying-in structure can provide big charging and discharging electric current, to realize the driving to large area array display panel.However, due to this There are bias currents in static state for the output stage of class A amplifier A, and often exist in single AMOLED row driving chips thousands of a defeated Go out buffer, thus this class A amplifier A it is total quiescent current it is larger, be unsatisfactory for the design requirement of low-power consumption.Another is used for The buffer of AMOLED column drive circuits is class-b amplifier, as shown in Fig. 2, different from class ab ammplifier, in class-b amplifier by Comparator and phase inverter are instead of the error amplifier in class ab ammplifier, the output end of amplifier and the positive input of comparator The output of connection, upper and lower two comparators is connected to the grid of output stage NMOS and PMOS, forms feedback loop.When defeated Enter end there are when step signal, comparator output is supply voltage VDD or ground VSS, and corresponding charge or discharge transistor is beaten It opens.When static, the output stage NMOS and PMOS of the circuit are in cut-off state, therefore quiescent current is not present in output stage.

Generally speaking, there are quiescent currents for the output of class ab ammplifier, do not meet the design requirement of low-power consumption, B class amplifiers For AB class amplifiers, structure is relatively simple, and quiescent dissipation is not present in output stage, and circuit overall power is relatively low, therefore very Gate source voltage suitable for AMOLED column drive circuits, but traditional class-b amplifier output stage transistor is up to power supply electricity Pressure, when load capacitance is very big, needs output transistor to have prodigious breadth length ratio, therefore when load capacitance further increases, The factors such as comprehensive area, power consumption are needed to advanced optimize circuit.

Invention content

In view of the foregoing deficiencies of prior art, the purpose of the present invention is to provide one kind for AMOLED row driving electricity The output buffer on road needs to integrate for solving output buffer in the prior art when load capacitance further increases The problem of factors such as area, power consumption advanced optimize circuit.

In order to achieve the above objects and other related objects, the present invention provides a kind of output for AMOLED column drive circuits Buffer, including:Rail-to-rail input stage circuit, bootstrapping grade circuit and output-stage circuit, the rail-to-rail input stage circuit connection The bootstrapping grade circuit, the bootstrapping grade circuit connect the output-stage circuit, the rail-to-rail input stage circuit, for just It is amplified to the difference of input signal and rp input signal;The bootstrapping grade circuit, for the control of output-stage circuit is electric Pressure rises above supply voltage or falls below ground voltage;The output-stage circuit, for being driven to output loading.

Preferably, the rail-to-rail input stage circuit includes the transistor of the first transistor~the 14th, the first crystal The source electrode of pipe connects the source electrode of the 7th transistor and its common end connection supply voltage, grid connect biasing circuit;Described second Drain electrode, the drain electrode of the source electrode and its common end connection the first transistor of the source electrode connection third transistor of transistor are separately connected the The drain electrode of the source electrode of 11 transistors and the 13rd transistor and its common end connects the 13rd transistor and the 14th transistor Connect the common end formed, grid connects the grid of the 4th transistor and its common end forms positive input;The third is brilliant The source electrode of drain electrode the tenth two-transistor of connection of body pipe and drain electrode and its common end company of the 14th transistor of its common end connection It is connected to and lifts grade circuit, grid forms the first negative direction input terminal;The source electrode of 4th transistor connects the source of the 5th transistor Pole and its common end connect the drain electrode of the 6th transistor, drain electrode is separately connected drain electrode and grid and its common end of the 7th transistor Connect the source electrode of the 9th transistor;The drain electrode of 5th transistor is separately connected drain electrode and the tenth transistor of the 8th transistor Source electrode and its common end connection bootstrapping grade circuit, grid form the second negative direction input terminal;The source electrode of 6th transistor Connect the source electrode of the 13rd transistor and its common end connection ground voltage, grid connection biasing circuit;7th transistor Grid connects the grid of the 8th transistor;The source electrode of 8th transistor connects supply voltage;The leakage of 9th transistor Pole connects the grid of the drain electrode of the 11st transistor and the grid and the tenth transistor of the 9th transistor of its first common end connection The common end formed is connected, the second common end connects the 11st transistor and connect the common end to be formed with the tenth two-transistor;Institute State the drain electrode of drain electrode the tenth two-transistor of connection of the tenth transistor;The source electrode of 14th transistor connects ground voltage.

Preferably, the length-width ratio of the transistor in the rail-to-rail input stage circuit includes following relationship:

Wherein,For the breadth length ratio of second transistor,For the breadth length ratio of third transistor,For the 4th crystal The breadth length ratio of pipe,For the breadth length ratio of the 5th transistor,For the breadth length ratio of the 7th transistor,For the 8th crystal The breadth length ratio of pipe,For the breadth length ratio of the 9th transistor,For the breadth length ratio of the tenth transistor,For the 11st crystalline substance The breadth length ratio of body pipe,For the breadth length ratio of the tenth two-transistor,For the breadth length ratio of the 13rd transistor,It is The breadth length ratio of 14 transistors.

Preferably, first inverting input and the second inverting input are connect with output signal, the positive input End is connect with input signal, forms unity gain buffer structure.

Preferably, the bootstrapping grade circuit includes two electric current ratios being made of the transistor of the 15th transistor~the 18th Compared with device circuit, two voltage comparator circuits being made of the two-transistor of the 19th transistor~the 20th, the 23rd switch The eighteenmo of transistor~second closes transistor, the first bootstrap capacitor and the second bootstrap capacitor.The source electrode of 15th transistor Connection supply voltage, drain electrode connect the drain electrode of the 16th transistor and its first common end is separately connected the 23rd switch The second end of the grid of transistor and the first bootstrap capacitor, the second common end connect the grid of the 19th transistor with it is described The grid of 20th transistor connects the common end to be formed, grid connects the grid of the 17th transistor and its common end connects rail To rail input stage circuit;16th transistor source electrode connection ground voltage, grid connect the 18th transistor grid and Its common end connects rail-to-rail input stage circuit;Described in the source electrode connection supply voltage of 17th transistor, drain electrode connect The drain electrode of 18th transistor and its first common end connect the grid of the 21st transistor and the described 22nd brilliant The grid of body pipe connects the common end to be formed, and the second common end is separately connected the grid and second of the 24th switching transistor certainly Lift the first end of capacitance;The source electrode of 18th transistor connects ground voltage;

The drain electrode and its common end connection the 25th of drain electrode the 20th transistor of connection of 19th transistor are opened It closes the grid of transistor and its common end connects the second eighteenmo and closes the grid of transistor, source electrode connection supply voltage;Described The source electrode of 20 transistors connects ground voltage;The source electrode connection supply voltage of 21st transistor, drain electrode connection second The drain electrode of ten two-transistors and grid and its common end connection the 27th of its common end the second sixteenmo of connection pass transistor The grid of switching transistor;The source electrode of 20th two-transistor connects ground voltage;23rd switching transistor Source electrode is separately connected the first end of the first bootstrap capacitor and the source electrode of the 25th switching transistor, drain electrode connection supply voltage; The source electrode of 24th switching transistor is separately connected the second end of the second bootstrap capacitor and the second sixteenmo closes transistor Source electrode, drain electrode connection ground voltage;Drain electrode the second eighteenmo of connection of 25th switching transistor closes the leakage of transistor Pole and its common end connection output-stage circuit;The drain electrode that second sixteenmo closes transistor connects the 27th switching transistor Drain electrode and its common end connect output-stage circuit;The source electrode of 27th switching transistor be separately connected supply voltage and Output-stage circuit;The source electrode that second eighteenmo closes transistor is separately connected ground voltage and output-stage circuit.

Preferably, the length-width ratio of the transistor in the bootstrapping grade circuit includes following relationship:

Wherein, (W/L)16For the breadth length ratio of the 16th transistor, (W/L)14For the breadth length ratio of the 14th transistor, (W/ L)15For the breadth length ratio of the 15th transistor, (W/L)8For the breadth length ratio of the 8th transistor, (W/L)18For the width of the 18th transistor Long ratio, (W/L)17For the breadth length ratio of the 17th transistor.

Preferably, when input signal is equal to output signal, the 15th transistor enters saturation region, the 16th transistor into Enter linear zone, the 17th transistor enters linear zone, and the 18th transistor enters saturation region.

Preferably, when input signal is equal to output signal, the 29th transistor of output-stage circuit and the 30th crystalline substance Body pipe is in cut-off state, and quiescent current is not present in output-stage circuit, while the 19th transistor to the second eighteenmo closes crystalline substance Quiescent current is also not present in body pipe.

Preferably, when input signal is more than output signal, the 15th transistor enters saturation region, the 16th transistor into Enter linear zone, the 17th transistor enters linear zone, and the 18th transistor enters saturation region.

Preferably, when input signal is more than output signal, the 29th transistor turns of output-stage circuit and to defeated Outlet charges, and the gate source voltage of the 29th transistor is -2VDD;30th transistor of output-stage circuit, which is in, to be cut Charge circuit is not present in the output end of only state, output-stage circuit.

Preferably, when input signal is less than output signal, the 15th transistor enters linear zone, the 16th transistor into Enter saturation region, the 17th transistor enters linear zone, and the 18th transistor enters saturation region.

Preferably, when input signal be less than output signal when, the 30th transistor turns of output-stage circuit and to output End is charged, and the gate source voltage of the 30th transistor is 2VDD;29th transistor of output-stage circuit is in cut-off Charge circuit is not present in the output end of state, output-stage circuit.

Preferably, the output-stage circuit is defeated for the Class B being made of the 1 19 transistor and the 30th transistor Go out a grade circuit, source electrode connection bootstrapping grade circuit and supply voltage, drain electrode the 30th crystal of connection of the 29th transistor The drain electrode of pipe and the output end of common end formation output-stage circuit, grid connection bootstrapping grade circuit;30th transistor Source electrode connection bootstrapping grade circuit and ground voltage, grid connection bootstrapping grade circuit.

Preferably, further include biasing circuit, for providing bias voltage, the biasing circuit for rail-to-rail input stage circuit Including the 31st transistor, the 30th two-transistor, the 33rd transistor, the 34th transistor, the described 31st The source electrode connection supply voltage of transistor, the source electrode of drain electrode the 30th two-transistor of connection and its common end connection the 31st are brilliant The grid of body pipe and the rail-to-rail input stage circuit of its common end connection;The drain electrode connection the 33rd of 30th two-transistor Transistor drain electrode and its common end connect the 30th two-transistor grid and the 33rd transistor grid Connect the common end formed;The source electrode of 33rd transistor connects the drain electrode of the 34th transistor and its common end connects Connect the grid of the 34th transistor and its common end connection track rail input stage circuit;The source electrode of 34th transistor Connect ground voltage.

Preferably, further include compensation resistance and load capacitance, for introducing left half of zero to operational amplifier into line frequency Rate compensate, it is described compensation resistance one end connect the output end of the output-stage circuit, the other end is separately connected output signal and Load capacitance, the load capacitance connect ground voltage.

Preferably, the transistor of the first transistor~third transistor, the 7th transistor~the tenth, the 15th transistor ~the two ten one transistor, the 23rd switching transistor, the 25th switching transistor, the 27th switching transistor, 29 transistors, the 31st transistor and the 30th two-transistor are NMOS transistor;4th transistor~the 6th The two-transistor of the transistor of transistor, the 11st transistor~the 14th, the 16th transistor~the 20th, the 24th switch are brilliant Body pipe, the second sixteenmo close transistor, the second eighteenmo closes transistor, the 33rd transistor and the 34th transistor and is PMOS transistor.

As described above, the output buffer for AMOLED column drive circuits of the present invention, has the advantages that:

The present invention by improve output stage transistor maximum gate source voltage, so as to use the smaller output stage of breadth length ratio Transistor realizes big driving current.Compared with prior art, the present invention has the advantages that quiescent current is small, simultaneously because filling The gate source voltage of efferent duct is close to twice of supply voltage when electric discharge, therefore the present invention can be in the identical condition of output pipe size The lower charging and discharging currents for providing bigger, can drive the load capacitance of bigger.

Description of the drawings

Fig. 1 is shown as the AB class output buffer schematic diagrames of (in the prior art) of the invention.

Fig. 2 is shown as the two-stage resistance string structure DAC schematic diagrames of (in the prior art) of the invention.

Fig. 3 is shown as the output buffer schematic diagram for AMOLED column drive circuits of the present invention.

Fig. 4 is shown as input signal of the present invention and is equal to output signal (VIN=VOUT) when, boot grade circuit and output-stage circuit Status diagram.

Fig. 5 is shown as input signal of the present invention and is more than output signal (VIN>VOUT) when, boot grade circuit and output-stage circuit Status diagram.

Fig. 6 is shown as input signal of the present invention and is more than output signal (VIN>VOUT) when, boot grade circuit and output-stage circuit Status diagram.

Component label instructions

1 the first bootstrap capacitors of biasing circuit C1

2 rail-to-rail the second bootstrap capacitors of input stage circuit C2

3 bootstrapping grade circuit VPNormal phase input end

4 output-stage circuit VINInput signal

VSS refers to ground voltage VNInverting input

VDD supply voltages VOUTOutput signal

RCCompensate the crystal of resistance T1~T22 the first transistors~the 22nd

CLLoad capacitance pipe

The 22nd switching transistors of T23~T28~the 29th transistor~34 two T29~T34

Eighteenmo closes transistor

Specific implementation mode

Illustrate that embodiments of the present invention, those skilled in the art can be by this specification below by way of specific specific example Disclosed content understands other advantages and effect of the present invention easily.The present invention can also pass through in addition different specific realities The mode of applying is embodied or practiced, the various details in this specification can also be based on different viewpoints with application, without departing from Various modifications or alterations are carried out under the spirit of the present invention.

Please refer to Fig. 3 to Fig. 6.It should be noted that the diagram provided in the present embodiment only illustrates this in a schematic way The basic conception of invention, package count when only display is with related component in the present invention rather than according to actual implementation in schema then Mesh, shape and size are drawn, when actual implementation kenel, quantity and the ratio of each component can be a kind of random change, and its Assembly layout kenel may also be increasingly complex.

In AMOLED column drive circuits, output buffer determine the speed, precision, output area of column drive circuit with And the performances such as power consumption, with the raising of display resolution and frame per second, system for output buffer performance requirement also increasingly It is high.Class-b amplifier and class ab ammplifier structure compared are relatively simple, and power consumption is relatively low, but traditional class-b amplifier output stage crystal The gate source voltage of pipe is up to supply voltage, when load capacitance is very big, needs output transistor to have prodigious breadth length ratio, therefore When load capacitance further increases, the factors such as comprehensive area, power consumption is needed to advanced optimize circuit.The present invention passes through The maximum gate source voltage for improving output stage transistor, so as to realize big drive with the smaller output stage transistor of breadth length ratio Streaming current.

Embodiment one

A kind of output buffer for AMOLED column drive circuits, including:Biasing circuit 1, rail-to-rail input stage circuit 2, bootstrapping grade circuit 3 and output-stage circuit 4, the rail-to-rail input stage circuit 2 are separately connected the bootstrapping grade circuit 3 and described Biasing circuit 1, the bootstrapping grade circuit 3 connect the output-stage circuit 4.The rail-to-rail input stage circuit 2, for forward direction Input signal and the difference of rp input signal are amplified;The bootstrapping grade circuit 3, for the control of output-stage circuit 4 is electric Pressure rises above supply voltage VDD or falls below ground voltage VSS;The output-stage circuit 4, for output loading into Row driving;The biasing circuit 1, for providing bias voltage for rail-to-rail input stage circuit 2.

As shown in figure 3, in the present embodiment, the rail-to-rail input stage circuit 2 includes the first transistor M1~the 14th brilliant Body pipe M14.Specifically, the source electrode of the first transistor M1 connects the source electrode of the 7th transistor M7 and its common end connects power supply Voltage VDD, grid connect biasing circuit 1;The source electrode and its public affairs of the source electrode connection third transistor M3 of the second transistor M2 The drain electrode, drain electrode of end connection the first transistor M1 is separately connected the source electrode and the 13rd transistor M13 of the 11st transistor M11 altogether Drain electrode and its common end connect the 13rd transistor M13 connect with the 14th transistor M14 the common end to be formed, grid connect The grid and its common end formation positive input V of 4th transistor M4P;The drain electrode connection the 12nd of the third transistor M3 The source electrode of transistor M12 and its common end connect in the drain electrode of the 14th transistor M14 and its common end connection bootstrapping grade circuit 3 The grid of the 16th transistor M16 connect that the common end to be formed, that grid forms first is anti-with the grid of the 18th transistor M18 Direction input terminal VN1;The source electrode of the 4th transistor M4 connects the source electrode of the 5th transistor M5 and its common end connection the 6th is brilliant Drain electrode, the drain electrode of body pipe M6 is separately connected the drain electrode of the 7th transistor M7 and the source electrode of the 9th transistor M9 and its common end connects The grid of 7th transistor M7 connect the common end to be formed with the grid of the 8th transistor M8;The drain electrode of the 5th transistor M5 It is separately connected in the drain electrode of the 8th transistor M8 and the source electrode of the tenth transistor M10 and its common end connection bootstrapping grade circuit 3 The grid of 15th transistor M15 connect the common end to be formed with the grid of the 17th transistor M17, grid forms the second negative side To input terminal VN2;The source electrode of the 6th transistor M6 connects the source electrode of the 13rd transistor M13 and its common end connection ground electricity VSS, grid is pressed to connect biasing circuit 1;The source electrode connection supply voltage VDD of the 8th transistor M8;9th transistor The drain electrode of the 11st transistor M11 of drain electrode connection of M9 and the grid and the tenth crystalline substance of the 9th transistor M9 of its first common end connection The grid of body pipe M10 connects the common end to be formed, and the second common end connects the 11st transistor M11 and the tenth two-transistor M12 Connect the common end formed;The drain electrode of the tenth two-transistor M12 of drain electrode connection of the tenth transistor M10;Described 14th The source electrode connection ground voltage VSS of transistor M14.

In the present embodiment, the bootstrapping grade circuit 3 includes being made of the 15th transistor M18 of transistor M15~the 18th Two current comparator circuits, two voltage comparators being made of the 19th two-transistor M20 of transistor M19~the 20th Circuit, the 23rd eighteenmos of switching transistor M23~second close transistor M28, the bootstrapping electricity of the first bootstrap capacitor C1 and second Hold C2.Wherein, the first end of the first bootstrap capacitor C1 and the second bootstrap capacitor C2 are top crown, and second end is bottom crown.Specifically , the source electrode connection supply voltage VDD of the 15th transistor M15, drain electrode connect the drain electrode of the 16th transistor M16 And its first common end is separately connected the grid of the 23rd switching transistor M23 and the second end of the first bootstrap capacitor C1, the The grid that two common ends connect the 19th transistor M19 connect the public affairs to be formed with the grid of the 20th transistor M20 End, the grid of the 17th transistor M17 of grid connection and its common end connect rail-to-rail input stage circuit 2 altogether;Described 16th Source electrode connection ground voltage VSS, the grid of transistor M16 connects the grid of the 18th transistor M18 and its common end connection rail arrives Rail input stage circuit 2;The source electrode connection supply voltage VDD of the 17th transistor M17, drain electrode connect the 18th crystal The drain electrode of pipe M18 and its first common end connects the grid of the 21st transistor M21 and the 20th two-transistor The grid of M22 connects the common end to be formed, and the second common end is separately connected the grid and second of the 24th switching transistor M24 The first end of bootstrap capacitor C2;The source electrode connection ground voltage VSS of the 18th transistor M18;The 19th transistor M19 Drain electrode connection the 20th transistor M20 drain electrode and its common end connect the 25th switching transistor M25 grid and its Common end connects the second eighteenmo and closes the grid of transistor M28, source electrode connection supply voltage VDD;The 20th transistor M20 Source electrode connection ground voltage VSS;The source electrode connection supply voltage VDD of the 21st transistor M21, drain electrode connection the 20th The drain electrode of two-transistor M22 and grid and its common end connection second of its common end the second sixteenmo of connection pass transistor M26 The grid of 17 switching transistor M27;The source electrode connection ground voltage VSS of the 20th two-transistor M22;Described 23rd The source electrode of switching transistor M23 be separately connected the first end of the first bootstrap capacitor and the source electrode of the 25th switching transistor M25, Drain electrode connection supply voltage VDD;The source electrode of the 24th switching transistor M24 is separately connected the of the second bootstrap capacitor C2 Two ends and the second sixteenmo close the source electrode of transistor, drain electrode connection ground voltage VSS;The 25th switching transistor M25's Drain electrode the second eighteenmo of connection closes the 30th transistor M30 of the drain electrode of transistor M28 and its common end connection output-stage circuit 4 Grid;Second sixteenmo closes the drain electrode of the 27th switching transistor M27 of drain electrode connection of transistor M26 and its is public The grid of 29th transistor M29 of end connection output-stage circuit 4;The source electrode of the 27th switching transistor M27 point Not Lian Jie supply voltage VDD and output-stage circuit 4 the 29th transistor M29 source electrode;Second eighteenmo closes crystal The source electrode of pipe M28 is separately connected the source electrode of the 30th transistor M30 of ground voltage VSS and output-stage circuit 4.

In the present embodiment, the output-stage circuit 4 is to be made of the 1 19 transistor M29 and the 30th transistor M30 Class B output-stage circuits 4.The source electrode connection bootstrapping grade circuit 3 and supply voltage VDD of the 29th transistor M29, The drain electrode of the 30th transistor M30 of drain electrode connection and the output end of common end formation output-stage circuit 4, grid connection bootstrapping grade electricity Road 3;Source electrode connection bootstrapping grade circuit 3 and ground voltage VSS, the grid connection bootstrapping grade circuit 3 of the 30th transistor M30.

Further include biasing circuit 1 in the present embodiment, for in rail-to-rail input stage circuit the first transistor M 1 and 6th transistor M6 provides bias voltage.The biasing circuit 1 includes the 31st transistor M31, the 30th two-transistor M32, the 33rd transistor M33 and the 34th transistor M34.Specifically, the source electrode of the 31st transistor M31 connects It connects supply voltage VDD, the source electrode of the 30th two-transistor M32 of drain electrode connection and its common end and connects the 31st transistor M31 Grid and its common end connect rail-to-rail input stage circuit 2 the first transistor M1 grid;30th two-transistor The drain electrode of M32 connects the drain electrode of the 33rd transistor M33 and its common end connects the grid of the 30th two-transistor M32 It connect the common end to be formed with the grid of the 33rd transistor M33;The source electrode of the 33rd transistor M33 connects The drain electrode of 34th transistor M34 and the grid of the 34th transistor M34 of its common end connection and its common end connection rail The grid of 16th transistor M36 of track input stage circuit;The source electrode of the 34th transistor M34 connects ground voltage VSS。

Further include compensation resistance R in the present embodimentCWith load capacitance CL, for introducing left half of zero to operational amplifier Carry out frequency compensation, the compensation resistance RCOne end connect the output end of the output-stage circuit 4, the other end be separately connected it is defeated Go out signal Vout and load capacitance CLOne end, the load capacitance CLOther end connection ground voltage VSS.

In the present embodiment, the length-width ratio of the transistor in the rail-to-rail input stage circuit 2 includes following relationship:

Wherein,For the breadth length ratio of second transistor,For the breadth length ratio of third transistor,For the 4th crystalline substance The breadth length ratio of body pipe,For the breadth length ratio of the 5th transistor,For the breadth length ratio of the 7th transistor,For the 8th crystalline substance The breadth length ratio of body pipe,For the breadth length ratio of the 9th transistor,For the breadth length ratio of the tenth transistor,It is the 11st The breadth length ratio of transistor,For the breadth length ratio of the tenth two-transistor,For the breadth length ratio of the 13rd transistor,For The breadth length ratio of 14th transistor.

In the present embodiment, the length-width ratio of the transistor in the bootstrapping grade circuit 3 includes following relationship:

Wherein, (W/L)16For the breadth length ratio of the 16th transistor, (W/L)14For the breadth length ratio of the 14th transistor, (W/ L)15For the breadth length ratio of the 15th transistor, (W/L)8For the breadth length ratio of the 8th transistor, (W/L)18For the width of the 18th transistor Long ratio, (W/L)17For the breadth length ratio of the 17th transistor.

The first transistor M1~third transistor the M3, the 7th transistors of transistor M7~the tenth in the present embodiment M10, the 15th transistor M21 of transistor M15~the 21st, the 23rd switching transistor M23, the 25th switch crystal Pipe M25, the 27th switching transistor M27, the 29th transistor M29, the 31st transistor M31 and the 32nd crystal Pipe M32 is NMOS transistor;4th transistor M4~the 6th transistor M6, the 11st crystal of transistor M11~the 14th Pipe M14, the 16th two-transistor M22 of transistor M16~the 20th, the 24th switching transistor M24, the second sixteenmo close brilliant It is that transistor is that body pipe M26, the second eighteenmo, which close transistor M28, the 33rd transistor M33 and the 34th transistor M34, PMOS transistor.

Embodiment two

According to embodiment one, the present embodiment two as shown in figure 3, the rail-to-rail input stage circuit 2 in the present embodiment reverse phase Input terminal VNIt links together with output buffer output signal Vout, the normal phase input end V of rail-to-rail input stage circuit 2PWith it is defeated Go out the input signal V of bufferINIt links together, forms unity gain buffer structure.Therefore, signal can be reduced to defeated Enter signal VIN(VIN=VP), output signal VOUT(VOUT=VN).According to input signal VINWith output signal VOUTRelationship, we Itd is proposed circuit is divided into following working condition.

(1) as input signal VINEqual to output signal VOUT(static, VIN=VOUT) when, the 15th transistor enters saturation Area, the 16th transistor enter linear zone, and the 17th transistor enters linear zone, and the 18th transistor enters saturation region.

Specifically, then flowing through the first branch electric current of the 7th transistor M7 to the 13rd transistor M13 and flowing through the 8th The second branch electric current of transistor M8 to the 14th transistor M14 are equal.Due to the 15th transistor M15 and the 16th transistor Without other branch currents between M16, therefore flow through the electric current I of the 15th transistor M1515Equal to flowing through the 16th transistor M16 Electric current I16, i.e. I15=I16

When input signal is equal to output signal (static, VIN=VOUT) when, then flow through M8 electric current be equal to flow through M14's Electric current, due toIf M15 and M16 has I all in saturation region15<I16, this and I15=I16Relationship It contradicts;If M15 is in linear zone, M16 is in saturation region, still there is I15<I16, equally and I15=I16Relationship contradict.Therefore Only when M15 is in saturation region, and M16 is in linear zone and just meets I15=I16Condition.Since M16 is in linear zone, cause M16 drain voltages reduce, close to ground voltage VSS.Similarly, due toSo that M17 enters linear zone, M18 Into saturation region, the drain voltage of M17 is caused to increase, close to supply voltage VDD.

At this point, the state of bootstrapping grade circuit 3 and Class B output-stage circuits 4 is as shown in figure 4, the line that wherein letter H is marked Indicate to be in high level circuit, the expression of alphabetical L mark be in low level circuit (letter the left side of correspondence line or on Side).Specifically, the drain electrode that the high level circuit includes the 17th transistor M17 connects the 18th transistor M18 Drain electrode and its first common end connect the grid of the 21st transistor M21 and the 20th two-transistor M22's Grid connects the common end to be formed, and the second common end is separately connected grid and the second bootstrapping of the 24th switching transistor M24 The first end of capacitance C2;The drain electrode of the 19th transistor M19 connects the drain electrode of the 20th transistor M20 and its common end connects It connects the grid of the 25th switching transistor M25 and its common end connects the grid that the second eighteenmo closes transistor M28;Described The source electrode of 23 switching transistor M23 connects the source electrode of the 25th switching transistor M25 and its common end connects first certainly Lift the first end of capacitance C1;The drain electrode that second sixteenmo closes transistor M26 connects the 27th switching transistor M27 Drain electrode and its common end connect the 29th transistor M29 grid;The source electrode of the 27th switching transistor M27 connects It meets the supply voltage VDD and connect the common end to be formed with the 29th transistor.Specifically, the low level circuit packet The drain electrode for including the 15th transistor M15 connects the drain electrode of the 16th transistor M16 and its first common end connects respectively Connect the grid of the 23rd switching transistor M23 and the second end of the first bootstrap capacitor C1, the second common end connection the described tenth The grid of nine transistor M19 connect the common end to be formed with the grid of the 20th transistor M20;21st crystal The drain electrode of pipe M21 connects the drain electrode of the 20th two-transistor M22 and its common end connects the second sixteenmo and closes transistor The grid of M26 and its common end connect the grid of the 27th switching transistor M27;Second sixteenmo closes transistor M26 Source electrode connect the 24th switching transistor M24 source electrode and its common end connect the second bootstrap capacitor C2 second end;Institute Drain electrode the second eighteenmo of connection for stating the 25th switching transistor M25 closes drain electrode and its common end connection the of transistor M28 The grid of 30 transistor M30.Wherein, the first end of the first bootstrap capacitor C1 and the second bootstrap capacitor C2 be top crown, second End is bottom crown.

It can be seen from figure 4 that the grid of the 23rd switching transistor M23 is low level, therefore the 23rd switch Transistor M23 conductings, supply voltage VDD is charged to by the first end of the first bootstrap capacitor C1, and under the first bootstrap capacitor C1 Step is connected with the drain electrode in low level 16th transistor M16, at this time second end voltage difference on the first bootstrap capacitor C1 The grid of about supply voltage VDD, the 27th switching transistor M27 are in low level, therefore the 27th switching transistor M27 is connected, and moves the grid of the 29th transistor M29 to high level supply voltage VDD so that the 29th transistor M29 Cut-off;Similarly, voltage difference is about supply voltage VDD in second end on the second bootstrap capacitor C2, and the second eighteenmo closes transistor M28 Conducting, moves the grid of the 30th transistor M30 to low level ground voltage VSS so that the 30th transistor M30 cut-offs.

In conclusion when input signal is equal to output signal, the first bootstrap capacitor C1 and the second bootstrap capacitor C2 upper the Two terminal voltage differences are supply voltage VDD, the 29th transistor M29 in Class B output-stage circuits 4 and the 30th crystal Pipe M30 is in cut-off state, therefore quiescent current, while the 19th transistor M19 to the 20th is not present in output-stage circuit Quiescent current is not present in eight transistor M28.

(2) when input signal is more than output signal (positive step signal, VIN>VOUT) when, the 15th transistor M15 enters Saturation region, the 16th transistor M16 enter linear zone, and the 17th transistor M17 enters linear zone, the 18th transistor M18 into Enter saturation region.

Specifically, when input signal is more than output signal (positive step signal, VIN>VOUT) when, then flow through the 8th crystal The electric current of pipe M8 is less than the electric current for flowing through the 14th transistor M14, due to the 15th transistor M15 and the 16th transistor M16 Between without other current branch, flow through the electric current I of the 15th transistor MM1515Equal to the electric current for flowing through the 16th transistor M16 I16.Due toIf the 15th transistor M15 and the 16th transistor M16 has I all in saturation region15 <I16, this and I15=I16Relationship contradict, if the 15th transistor M15 is in linear zone, the 16th transistor M16 is in full And area, still there is I15<I16, equally and I15=I16Relationship contradict, therefore only the 15th transistor M15 is in saturation region, and 16th transistor M16 is in linear zone and just meets I15=I16Condition.Since the 16th transistor M16 is in linear zone, lead The reduction of the 16th transistor M16 drain voltages is caused, close to ground voltage VSS.For the 17th transistor M17 and the 18th transistor M18, by adjusting suitableWith(at this timeStill less than) so that the 18th is brilliant Body pipe M18 enters linear zone, and the 17th transistor M17 enters saturation region, and the drain electrode of the 18th transistor M18 is pulled down to close Ground voltage VSS.

At this point, the state of bootstrapping grade circuit 3 and Class B output-stage circuits 4 is as shown in figure 5, the line that wherein letter H is marked Indicate that the circuit in high level, the line of alphabetical L marks indicate that (letter is on the left side of corresponding line in low level circuit Or top).Specifically, the drain electrode that the high level circuit includes the 19th transistor M19 connects the 20th transistor M20 Drain electrode and its common end connect the 25th switching transistor M25 grid and its common end connect the second eighteenmo close crystal The grid of pipe M28;The drain electrode of the 21st transistor M21 connects drain electrode and its common end of the 20th two-transistor M22 It connects the second sixteenmo and closes the grid of transistor M26 and the grid of the 27th switching transistor M27 of its common end connection;It is described The source electrode of 25th switching transistor M25 connects the source electrode of the 23rd switching transistor M23 and its common end connects The first end of first bootstrap capacitor C1;The source electrode of the 27th switching transistor M27 connects the supply voltage VDD and institute It states the 29th transistor M29 and connects the common end to be formed.Specifically, the low level circuit includes the 15th transistor The drain electrode of M15 connects the drain electrode of the 16th transistor M16 and its first common end is separately connected the 23rd switch crystal The second end of the grid of pipe M23 and the first bootstrap capacitor C1, the second common end connect the grid of the 19th transistor M19 with The grid of the 20th transistor M20 connects the common end to be formed;The drain electrode connection described the of the 17th transistor M17 The drain electrode of 18 transistor M18 and its first common end connects the grid and the described 20th of the 21st transistor M21 The grid of two-transistor M22 connects the common end to be formed, and the second common end is separately connected the grid of the 24th switching transistor M24 The first end of pole and the second bootstrap capacitor C2;The drain electrode of the 25th switching transistor M25 connects the second eighteenmo and closes crystalline substance The drain electrode of body pipe M28 and the grid of the 30th transistor M30 of its common end connection;Second sixteenmo closes transistor M26's Source electrode connects the source electrode of the 24th switching transistor M24 and its common end connects the second end of the second bootstrap capacitor C2, drain electrode It connects the drain electrode of the 27th switching transistor M27 and its common end connects the grid of the 29th transistor M29.Its In, the first end of the first bootstrap capacitor C1 and the second bootstrap capacitor C2 are top crown, and second end is bottom crown.

As can be seen from FIG. 5, the grid of the 24th switching transistor M24 becomes low level, therefore the 24th switch is brilliant The M24 cut-offs of body pipe, the lower step floating of the second bootstrap capacitor C2, first end become ground voltage VSS from supply voltage VDD, due to When stable state, second end voltage difference is supply voltage VDD, therefore step current potential under the second bootstrap capacitor C2 on the second bootstrap capacitor C2 - VDD is become from VSS at this time, it is high level that the second sixteenmo, which closes transistor M26 grids, and the second sixteenmo, which closes transistor M26, to be beaten It opens, on the grid that step negative supply voltage-VSS under the second bootstrap capacitor C2 is loaded to the 29th transistor M29, at this time second 19 transistor M29 are opened and are charged to output end, and the 29th transistor M29 gate source voltages are -2VDD.For second 13 switching transistor M23, the 25th switching transistor M25, the second eighteenmo close transistor M28 and the 30th transistor For M30, state is identical as steady definition status, and discharge loop is not present in the 30th transistor M30 cut-offs, output end.

(3) when input signal is less than output signal (negative sense step signal, VIN<VOUT) when, the 15th transistor M15 enters Linear zone, the 16th transistor M16 enter saturation region, and the 17th transistor M17 enters linear zone, the 18th transistor M18 into Enter saturation region.

Specifically, the electric current for then flowing through the 8th transistor M8, which is more than, flows through the electric current of the 14th transistor M14, due to the Without other current branch between 15 transistor M15 and the 16th transistor M16, the electric current I of the 15th transistor M15 is flowed through15 Equal to the electric current I for flowing through the 16th transistor M1616.By adjusting suitableWith(at this timeStill So it is less than), the 15th transistor M15 enters linear zone by saturation region, and the 16th transistor M16 is entered by linear zone Saturation region, the drain electrode of the 16th transistor M16 are pulled high to the current potential close to supply voltage VDD, and the 17th transistor M17 and The state of 18th transistor M18 is identical when keeping with static state, i.e. the 17th transistor M17 is in linear zone, the 18th crystal Pipe M18 is in saturation region, and the drain electrode of the 18th transistor M18 is pulled high to the current potential close to supply voltage VDD.

At this point, the state of bootstrapping grade circuit 3 and Class B output-stage circuits 4 is as shown in fig. 6, the line that wherein letter H is marked Indicate that the circuit in high level, the line of alphabetical L marks indicate that (letter is on the left side of corresponding line in low level circuit Or top).Specifically, the drain electrode that the high level circuit includes the 15th transistor M15 connects the 16th crystal The drain electrode of pipe M16 and its first common end is separately connected the grid and the first bootstrap capacitor C1 of the 23rd switching transistor M23 Second end, the second common end connects the grid of the 19th transistor M19 and the grid of the 20th transistor M20 connects Connect the common end to be formed;The drain electrode of the 17th transistor M17 connect the drain electrode of the 18th transistor M18 and its first The grid that common end connects the 21st transistor M21 connect with the grid of the 20th two-transistor M22 to be formed Common end, the second common end are separately connected the grid of the 24th switching transistor M24 and the first end of the second bootstrap capacitor C2; The source electrode of the 25th switching transistor M25 connects source electrode and its common end of the 23rd switching transistor M23 The first end of the first bootstrap capacitor C1, the drain electrode of drain electrode the second eighteenmo of connection pass transistor M28 and its common end is connected to connect The grid of 30th transistor M30;Second sixteenmo closes drain electrode connection the 27th switch crystal of transistor M26 The drain electrode of pipe M27 and the grid of the 29th transistor M29 of its common end connection;The 27th switching transistor M27's Source electrode connection supply voltage VDD connect the common end to be formed with the source electrode of the 29th transistor.Specifically, the low level line Road includes the drain electrode of the 20th transistor M20 of drain electrode connection of the 19th transistor M19 and its common end connection the 20th The grid and its common end the second eighteenmo of connection of five switching transistor M25 close the grid of transistor M28;Described 21st is brilliant The source electrode of body pipe M21 connects the source electrode of the 20th two-transistor M22 and its common end connects the second sixteenmo and closes transistor M26's Grid and its common end connect the grid of the 27th switching transistor M27;The source electrode of the 24th switching transistor M24 It connects second sixteenmo and closes the source electrode of transistor M26 and the second end of the second bootstrap capacitor C2 of its common end connection.Its In, the first end of the first bootstrap capacitor C1 and the second bootstrap capacitor C2 are top crown, and second end is bottom crown.

As can be seen from FIG. 6, the grid of the 23rd switching transistor M23 becomes high level, therefore the 23rd switch is brilliant Body pipe M23 ends, and step floating on the first bootstrap capacitor C1, second end becomes VDD from VSS, when due to stable state, the first bootstrapping electricity It is VDD to hold the upper second end voltage differences of C1, therefore step current potential becomes 2VDD from VDD at this time on the second bootstrap capacitor C2, the 20th Five switching transistor M25 grids are low level, and the 25th switching transistor M25 is opened, by the first bootstrap capacitor C1 subordinates Plate voltage 2VDD is loaded on the grid of the 30th transistor M30, and the 30th transistor M30 is opened and put to output end at this time Electricity, M30 gate source voltages are 2VDD.Transistor M26, the 27th are closed for the 24th switching transistor M24, the second sixteenmo For switching transistor M27 and the 20th transistor M20, state is identical as steady definition status, and the 29th transistor M29 is cut Only, charge circuit is not present in output end.

In conclusion the present invention by improve output stage transistor maximum gate source voltage, so as to breadth length ratio compared with Small output stage transistor realizes big driving current.Compared with prior art, the present invention has the advantages that quiescent current is small, Simultaneously because the gate source voltage of efferent duct is close to twice of supply voltage when charge and discharge, therefore the present invention can be in output pipe size The charging and discharging currents for providing bigger under the same conditions, can drive the load capacitance of bigger.So the present invention effectively overcomes Various shortcoming in the prior art and have high industrial utilization.

The above-described embodiments merely illustrate the principles and effects of the present invention, and is not intended to limit the present invention.It is any ripe The personage for knowing this technology can all carry out modifications and changes to above-described embodiment without violating the spirit and scope of the present invention.Cause This, institute is complete without departing from the spirit and technical ideas disclosed in the present invention by those of ordinary skill in the art such as At all equivalent modifications or change, should by the present invention claim be covered.

Claims (15)

1. a kind of output buffer for AMOLED column drive circuits, the output buffer include:Rail-to-rail input stage electricity Road, bootstrapping grade circuit and output-stage circuit, the rail-to-rail input stage circuit connect the bootstrapping grade circuit, the bootstrapping grade electricity Road connects the output-stage circuit;
The rail-to-rail input stage circuit, is amplified for the difference to positive input signal and rp input signal;
The output-stage circuit, for being driven to output loading, it is characterised in that:The bootstrapping grade circuit will be for that will export The control voltage of grade circuit rises above supply voltage or falls below ground voltage.
2. the output buffer according to claim 1 for AMOLED column drive circuits, it is characterised in that:The rail arrives Rail input stage circuit includes the transistor of the first transistor~the 14th;
The source electrode of the first transistor connects the source electrode of the 7th transistor and its common end connection supply voltage, grid connect partially Circuits;
Drain electrode, the leakage of the source electrode and its common end connection the first transistor of the source electrode connection third transistor of the second transistor Pole be separately connected the drain electrode of the source electrode and the 13rd transistor of the 11st transistor and its common end connect the 13rd transistor with 14th transistor connects the common end to be formed, grid connects the grid of the 4th transistor and its common end forms positive input End;
The leakage of the source electrode and the 14th transistor of its common end connection of drain electrode the tenth two-transistor of connection of the third transistor Pole and its common end connection bootstrapping grade circuit, grid the first negative direction input terminal of formation;
The source electrode of 4th transistor connects the source electrode of the 5th transistor and its common end connects the drain electrode of the 6th transistor, leakage Pole be separately connected the drain electrode of the 7th transistor and the source electrode of the 9th transistor and its common end connect the grid of the 7th transistor with The grid of 8th transistor connects the common end to be formed;
The drain electrode of 5th transistor is separately connected source electrode and its common end of the drain electrode and the tenth transistor of the 8th transistor Connection bootstrapping grade circuit, grid form the second negative direction input terminal;
The source electrode of 6th transistor connects the source electrode of the 13rd transistor and its common end connection ground voltage, grid connect partially Circuits;
The source electrode of 8th transistor connects supply voltage;
The drain electrode of 9th transistor connects the drain electrode of the 11st transistor and its first common end connects the 9th transistor Grid connect the common end to be formed with the grid of the tenth transistor, and the second common end connects the 11st transistor and the 12nd crystal Pipe connects the common end to be formed;
The drain electrode of drain electrode the tenth two-transistor of connection of tenth transistor;
The source electrode of 14th transistor connects ground voltage.
3. the output buffer according to claim 2 for AMOLED column drive circuits, it is characterised in that:The rail arrives The length-width ratio of transistor in rail input stage circuit includes following relationship:
Wherein,For the breadth length ratio of second transistor,For the breadth length ratio of third transistor,For the 4th transistor Breadth length ratio,For the breadth length ratio of the 5th transistor,For the breadth length ratio of the 7th transistor,For the width of the 8th transistor Long ratio,For the breadth length ratio of the 9th transistor,For the breadth length ratio of the tenth transistor,For the 11st transistor Breadth length ratio,For the breadth length ratio of the tenth two-transistor,For the breadth length ratio of the 13rd transistor,For the 14th crystalline substance The breadth length ratio of body pipe.
4. the output buffer according to claim 2 for AMOLED column drive circuits, it is characterised in that:Described first Negative direction input terminal and the second negative direction input terminal are connect with output signal, and the positive input is connect with input signal, group At unity gain buffer structure.
5. the output buffer according to claim 1 for AMOLED column drive circuits, it is characterised in that:The bootstrapping Grade circuit includes two current comparator circuits being made of the transistor of the 15th transistor~the 18th, by the 19th transistor Two voltage comparator circuits of the~the two ten two-transistor composition, the eighteenmo of the 23rd switching transistor~second close crystal Pipe, the first bootstrap capacitor and the second bootstrap capacitor;
The source electrode connection supply voltage of 15th transistor, drain electrode connect the drain electrode of the 16th transistor and its first Common end is separately connected the grid of the 23rd switching transistor and the second end of the first bootstrap capacitor, and the second common end connects institute It states the grid of the 19th transistor and the grid of the 20th transistor connect the common end to be formed, the 17th crystalline substance of grid connection The grid of body pipe and the rail-to-rail input stage circuit of its common end connection;
Source electrode connection ground voltage, the grid of 16th transistor connect the grid of the 18th transistor and its common end connects Rail-to-rail input stage circuit;
The source electrode connection supply voltage of 17th transistor, drain electrode connect the drain electrode of the 18th transistor and its first The grid that common end connects the 21st transistor connect the common end to be formed with the grid of the 20th two-transistor, Second common end is separately connected the grid of the 24th switching transistor and the first end of the second bootstrap capacitor;
The source electrode of 18th transistor connects ground voltage;
The drain electrode and its common end connection the 25th of drain electrode the 20th transistor of connection of 19th transistor switch brilliant The grid of body pipe and its common end connect the second eighteenmo and close the grid of transistor, source electrode connection supply voltage;
The source electrode of 20th transistor connects ground voltage;
The source electrode connection supply voltage of 21st transistor, drain electrode connect the drain electrode of the 20th two-transistor and its is public End the second sixteenmo of connection closes the grid of transistor and its common end connects the grid of the 27th switching transistor;
The source electrode of 20th two-transistor connects ground voltage;
The source electrode of 23rd switching transistor is separately connected the first end and the 25th switch crystalline substance of the first bootstrap capacitor Source electrode, the drain electrode connection supply voltage of body pipe;
The source electrode of 24th switching transistor is separately connected the second end of the second bootstrap capacitor and the second sixteenmo closes crystalline substance Source electrode, the drain electrode connection ground voltage of body pipe;
Drain electrode the second eighteenmo of connection of 25th switching transistor closes the drain electrode of transistor and the connection of its common end is defeated Go out a grade circuit;Second sixteenmo closes the drain electrode of drain electrode the 27th switching transistor of connection of transistor and its common end connects Connect output-stage circuit;The source electrode of 27th switching transistor is separately connected supply voltage and output-stage circuit;
The source electrode that second eighteenmo closes transistor is separately connected ground voltage and output-stage circuit.
6. the output buffer according to claim 5 for AMOLED column drive circuits, it is characterised in that:The bootstrapping The length-width ratio of transistor in grade circuit includes following relationship:
Wherein, (W/L)16For the breadth length ratio of the 16th transistor, (W/L)14For the breadth length ratio of the 14th transistor, (W/L)15For The breadth length ratio of 15th transistor, (W/L)8For the breadth length ratio of the 8th transistor, (W/L)18For the breadth length ratio of the 18th transistor, (W/L)17For the breadth length ratio of the 17th transistor.
7. the output buffer according to claim 6 for AMOLED column drive circuits, it is characterised in that:When input is believed When number being equal to output signal, the 15th transistor enters saturation region, and the 16th transistor enters linear zone, the 17th transistor into Enter linear zone, the 18th transistor enters saturation region.
8. the output buffer according to claim 6 for AMOLED column drive circuits, it is characterised in that:When input is believed Number be equal to output signal when, the 29th transistor of output-stage circuit and the 30th transistor are in cut-off state, output Quiescent current is not present in grade circuit, while the 19th transistor to the second eighteenmo closes transistor and quiescent current is also not present.
9. the output buffer according to claim 6 for AMOLED column drive circuits, it is characterised in that:When input is believed When number being more than output signal, the 15th transistor enters saturation region, and the 16th transistor enters linear zone, the 17th transistor into Enter linear zone, the 18th transistor enters saturation region.
10. the output buffer according to claim 6 for AMOLED column drive circuits, it is characterised in that:Work as input When signal is more than output signal, the 29th transistor turns of output-stage circuit simultaneously charge to output end, and the 20th The gate source voltage of nine transistors is -2VDD;30th transistor of output-stage circuit is in cut-off state, output-stage circuit it is defeated Charge circuit is not present in outlet.
11. the output buffer according to claim 6 for AMOLED column drive circuits, it is characterised in that:Work as input When signal is less than output signal, the 15th transistor enters linear zone, and the 16th transistor enters saturation region, the 17th transistor Into linear zone, the 18th transistor enters saturation region.
12. the output buffer according to claim 6 for AMOLED column drive circuits, it is characterised in that:Work as input When signal is less than output signal, the 30th transistor turns of output-stage circuit simultaneously charge to output end, and the 30th is brilliant The gate source voltage of body pipe is 2VDD;29th transistor of output-stage circuit is in cut-off state, the output of output-stage circuit Charge circuit is not present in end.
13. the output buffer according to claim 1 for AMOLED column drive circuits, it is characterised in that:It is described defeated It is the Class B output-stage circuits being made of the 1 19 transistor and the 30th transistor to go out grade circuit;
The leakage of the source electrode connection bootstrapping grade circuit and supply voltage, drain electrode the 30th transistor of connection of 29th transistor Pole and common end form the output end of output-stage circuit, grid connection bootstrapping grade circuit;
Source electrode connection bootstrapping grade circuit and ground voltage, the grid connection bootstrapping grade circuit of 30th transistor.
14. the output buffer according to claim 1 for AMOLED column drive circuits, it is characterised in that:Further include Biasing circuit, for providing bias voltage for rail-to-rail input stage circuit, the biasing circuit includes the 31st transistor, the 30 two-transistors, the 33rd transistor and the 34th transistor;
The source electrode connection supply voltage of 31st transistor, drain electrode connect the source electrode of the 30th two-transistor and its is public The grid and the rail-to-rail input stage circuit of its common end connection of the 31st transistor of end connection;
The drain electrode and its common end connection the described 30th of drain electrode the 33rd transistor of connection of 30th two-transistor The grid of two-transistor connect the common end to be formed with the grid of the 33rd transistor;
The source electrode of 33rd transistor connects the drain electrode of the 34th transistor and its common end connection the 34th is brilliant The grid of body pipe and its common end connection track rail input stage circuit;
The source electrode of 34th transistor connects ground voltage.
15. the output buffer according to claim 1 for AMOLED column drive circuits, it is characterised in that:Further include Resistance and load capacitance are compensated, frequency compensation is carried out to operational amplifier for introducing left half of zero, the compensation resistance One end connects the output end of the output-stage circuit, the other end is separately connected output signal and one end of load capacitance, described negative The other end for carrying capacitance connects ground voltage.
CN201610719581.3A 2016-08-24 2016-08-24 A kind of output buffer for AMOLED column drive circuits CN106251808B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610719581.3A CN106251808B (en) 2016-08-24 2016-08-24 A kind of output buffer for AMOLED column drive circuits

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610719581.3A CN106251808B (en) 2016-08-24 2016-08-24 A kind of output buffer for AMOLED column drive circuits

Publications (2)

Publication Number Publication Date
CN106251808A CN106251808A (en) 2016-12-21
CN106251808B true CN106251808B (en) 2018-07-20

Family

ID=57596445

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610719581.3A CN106251808B (en) 2016-08-24 2016-08-24 A kind of output buffer for AMOLED column drive circuits

Country Status (1)

Country Link
CN (1) CN106251808B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106849938B (en) * 2016-12-23 2020-08-28 深圳市国微电子有限公司 Input buffer circuit

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100490623B1 (en) * 2003-02-24 2005-05-17 삼성에스디아이 주식회사 Buffer circuit and active matrix display device using the same
WO2009081619A1 (en) * 2007-12-20 2009-07-02 Sharp Kabushiki Kaisha Buffer and display device
JP5125569B2 (en) * 2008-02-08 2013-01-23 ソニー株式会社 Bootstrap circuit
EP2634774B1 (en) * 2012-02-28 2019-09-18 Nxp B.V. Track and hold circuit and method

Also Published As

Publication number Publication date
CN106251808A (en) 2016-12-21

Similar Documents

Publication Publication Date Title
US9454940B1 (en) Gate driver on array (GOA) circuit and LCD device using the same
CN104575398B (en) Image element circuit and its driving method, display device
CN103996367B (en) Shifting register, gate drive circuit and display device
CN101552841B (en) Output amplifier circuit, output circuit, data driver and display device
CN100426526C (en) Thin-film semiconductor device and producing method thereof
CN100432886C (en) Double ring low differential voltage linear voltage stabilizer circuit
US7551030B2 (en) Two-stage operational amplifier with class AB output stage
US7154332B2 (en) Differential amplifier, data driver and display device
US7760180B2 (en) Drive circuit, operation state detection circuit, and display device
JP3830339B2 (en) High slew rate differential amplifier
CN104157236B (en) A kind of shift register and gate driver circuit
CN104282255B (en) Shift register, gate driver circuit and driving method thereof, display device
CN102045035B (en) Low-power consumption broadband high-gain high-swing rate single-level operation transconductance amplifier
WO2017096658A1 (en) Goa circuit based on ltps semiconductor thin film transistor
GB2550508A (en) Goa circuit for liquid crystal display device
CN102446488B (en) Semiconductor device
CN100536326C (en) Differential amplifier, digital-to-analog converter, and display device
US20050068105A1 (en) Differential AB class amplifier circuit and drive circuit using the same
TWI405406B (en) Differential amplifier circuit
US20080174462A1 (en) Data driver and display device
Lee et al. Design of low-power analog drivers based on slew-rate enhancement circuits for CMOS low-dropout regulators
WO2017101200A1 (en) Ltps semiconductor thin-film transistor-based goa circuit
CN1777026B (en) Voltage comparator circuit with symmetric circuit topology
CN104916257A (en) Pixel circuit, drive method thereof, display panel and display device
CN103309507B (en) A kind of display driver circuit, method and display unit of touching

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant