CN109817157A

CN109817157A - A pixel driving circuit and its control method, and a display device

Info

Publication number: CN109817157A
Application number: CN201910223006.8A
Authority: CN
Inventors: 肖丽; 玄明花; 刘冬妮; 陈亮; 陈昊
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2019-03-22
Filing date: 2019-03-22
Publication date: 2019-05-28

Abstract

The invention discloses a pixel driving circuit, a control method thereof, and a display device, wherein the pixel driving circuit is respectively connected with an external control circuit and N light-emitting elements, and an input sub-circuit is respectively connected with the external control circuit, a first node and a reference signal. The terminal is connected with the data signal terminal; the reading sub-circuit is respectively connected with the external control sub-circuit, the first node and the reading signal terminal; the node control sub-circuit is respectively connected with the first node, the first scanning terminal, the second scanning terminal, The first power supply terminal, the second node and the third node are connected; the lighting control sub-circuit is respectively connected with the second node, the third node, the first power supply terminal, the N lighting control terminals and the N lighting elements, and the lighting control terminal is connected to the The light-emitting elements correspond one-to-one. The technical solution provided by the present invention can reduce the number of components in the pixel driving circuit in the OLED display panel, thereby increasing the pixel density of the OLED display panel.

Description

A kind of pixel-driving circuit and its control method, display device

Technical field

The present invention relates to field of display technology, and in particular to a kind of pixel-driving circuit and its control method, display device.

Background technique

Organic Light Emitting Diode (Organic Light Emitting Diode, abbreviation OLED) is sent out as a kind of current mode Optical device has many advantages, such as self-luminous, quick response, wide viewing angle and can be made in flexible substrate and be widely used in High-performance display field.

It in the related technology, include multiple pixel units and multiple pixel-driving circuits, pixel unit in OLED display panel It is corresponded with pixel-driving circuit, pixel unit is connected with corresponding pixel-driving circuit, and each pixel unit is as pixel The light-emitting component of driving circuit driving, specifically, including that driving transistor is driven with exporting to light-emitting component in pixel-driving circuit Streaming current.Through inventors have found that in pixel-driving circuit included by OLED display panel component (such as: film crystal Pipe) quantity it is more, to affect the promotion of the pixel density of OLED display panel.

It should be noted that information is only used for reinforcing the understanding to background disclosed in above-mentioned background technology part, therefore It may include the information not constituted to the prior art known to persons of ordinary skill in the art.

Summary of the invention

In order to solve the above-mentioned technical problems, the present invention provides a kind of pixel-driving circuit and its control methods, display dress It sets, reduces the quantity of the component in pixel-driving circuit, and then improve the pixel density of OLED display panel.

In a first aspect, the embodiment of the present invention provides a kind of pixel-driving circuit, respectively with external control circuit and N number of shine Element connection, the pixel-driving circuit include: input sub-circuit, read sub-circuit, node control sub-circuit and light emitting control Sub-circuit, N >=2；

The input sub-circuit connects with external control circuit, first node, reference signal end and data signal end respectively It connects, for providing the signal of reference signal end or data signal end to first node under the control of external control circuit；

The reading sub-circuit controls sub-circuit with outside respectively, and first node is connected with signal end is read, for outside Portion controls under the control of sub-circuit, from the signal for reading signal end reading first node；

The node control sub-circuit, respectively with first node, the first scanning end, the second scanning end, the first power end, Two nodes are connected with third node, for providing the signal of first node to second node under the control of the first scanning end, Under the control of second scanning end, the signal of first node is provided to third node；

The light emitting control sub-circuit, respectively with second node, third node, the first power end, N number of light emitting control end and N number of light-emitting component connection, for driving N number of luminous member under the control of second node, third node and N number of light emitting control end Part shines, and the light emitting control end and the light-emitting component correspond.

Optionally, the input sub-circuit includes: first switch and the second switch, and the first switch and described second is opened It closes and is opened or closed by external control circuit control；

The first end of the first switch is connect with reference signal end, and second end is connect with first node；

The first end of the second switch is connect with data signal end, and second end is connect with first node.

Optionally, the reading sub-circuit includes: third switch, and the third switch is controlled by the external control circuit It is opened or closed；

The first end of the third switch is connect with signal end is read, and second end is connect with first node.

Optionally, the node control sub-circuit includes: first switch transistor, second switch transistor, first capacitor With the second capacitor；

The control electrode of the first switch transistor is connect with the first scanning end, and the first pole is connect with first node, Second pole is connect with second node；

The control electrode of the second switch transistor is connect with the second scanning end, and the first pole is connect with first node, Second pole is connect with third node；

The first end of the first capacitor is connect with second node, and second end is connect with the first power end；

The first end of second capacitor is connect with second node, and second end is connect with third node.

Optionally, each light-emitting component includes: Organic Light Emitting Diode, the anode of the Organic Light Emitting Diode with it is described The connection of light emitting control sub-circuit, cathode are connect with second source end.

Optionally, the light emitting control sub-circuit includes: that driving transistor and third switching transistor~N+2 switch are brilliant Body pipe；

The control electrode of the driving transistor connect with second node, and source electrode is connect with third node, is drained and the The connection of one power end；

The control electrode of i-th switching transistor is connect with the i-th -2 light emitting control ends, and the first pole is connect with third node, The anode of its second pole Organic Light Emitting Diode corresponding with the i-th -2 light emitting control ends connects, 3≤i≤N+2.

Optionally, the input sub-circuit includes: first switch and the second switch；The reading sub-circuit includes: third Switch；The node control sub-circuit includes: first switch transistor, second switch transistor, first capacitor and the second capacitor； The light emitting control sub-circuit includes: driving transistor and third switching transistor~N+2 switching transistor；

The first end of the second switch is connect with data signal end, and second end is connect with first node；

The first end of the third switch is connect with signal end is read, and second end is connect with first node；

The first end of second capacitor is connect with second node, and second end is connect with third node；

The control electrode of i-th switching transistor is connect with the i-th -2 light emitting control ends, and the first pole is connect with third node, The light-emitting component connection corresponding with the i-th -2 light emitting control ends of its second pole, 3≤i≤N+2.

Optionally, the external control sub-circuit is also used to the signal according to first node, obtains the threshold of driving transistor Threshold voltage, and offset voltage is obtained according to threshold voltage, it is also used to provide the offset voltage to the data signal end, so that It obtains the pixel-driving circuit and driving transistor is compensated according to offset voltage.

Second aspect, the embodiment of the present invention also provide a kind of control method of pixel-driving circuit, are applied to above-mentioned pixel In driving circuit, which comprises

It inputs sub-circuit and provides the signal at reference signal end to first node, node control sub-circuit is in the first scanning end Under control, the signal of first node is provided to second node, under the control of the second scanning end, provides first segment to third node The signal of point；

It inputs sub-circuit and provides the signal of data signal end to first node, node control sub-circuit is in the first scanning end Under control, the signal of first node is provided to second node；

Node control sub-circuit provides the signal of third node under the control of the second scanning end, to first node, reads Sub-circuit is under the control of external control sub-circuit, from the signal for reading signal end reading first node；

Node control sub-circuit provides the signal of first node under the control of the first scanning end, to second node, shines It controls sub-circuit to be used under the control of second node, third node and N number of light emitting control end, N number of light-emitting component is driven to shine.

The third aspect, the embodiment of the present invention also provide a kind of display device, comprising: above-mentioned pixel-driving circuit.

The embodiment of the present invention provides a kind of pixel-driving circuit and its control method, display device, wherein pixel driver electricity Road is connect with external control circuit and N number of light-emitting component respectively, pixel-driving circuit include: input sub-circuit, read sub-circuit, Node control sub-circuit and light emitting control sub-circuit, N >=2；Input sub-circuit, respectively with external control circuit, first node, ginseng It examines signal end to connect with data signal end, for providing reference signal end to first node under the control of external control circuit Or the signal of data signal end；Sub-circuit is read, controls sub-circuit with outside respectively, first node is connected with signal end is read, For reading the signal of first node from reading signal end under the control of external control sub-circuit；Node control sub-circuit, point It is not connect with first node, the first scanning end, the second scanning end, the first power end, second node and third node, for the Under the control of one scanning end, the signal of first node is provided to second node, under the control of the second scanning end, to third node The signal of first node is provided；Light emitting control sub-circuit, respectively with second node, third node, the first power end, it is N number of shine Control terminal is connected with N number of light-emitting component, for driving N under the control of second node, third node and N number of light emitting control end A light-emitting component shines, and light emitting control end and light-emitting component correspond.Pixel-driving circuit provided in an embodiment of the present invention with A plurality of light-emitting elements connection can be reduced in OLED display panel in pixel-driving circuit with driving a plurality of light-emitting elements to shine The quantity of component, and then promote the pixel density of OLED display panel.

Other features and advantages of the present invention will be illustrated in the following description, also, partly becomes from specification It obtains it is clear that understand through the implementation of the invention.The objectives and other advantages of the invention can be by specification, right Specifically noted structure is achieved and obtained in claim and attached drawing.

Detailed description of the invention

Attached drawing is used to provide to further understand technical solution of the present invention, and constitutes part of specification, with this The embodiment of application technical solution for explaining the present invention together, does not constitute the limitation to technical solution of the present invention.

Fig. 1 is the structural schematic diagram of pixel-driving circuit provided in an embodiment of the present invention；

Fig. 2 is the equivalent circuit diagram of input sub-circuit provided in an embodiment of the present invention；

Fig. 3 is the equivalent circuit diagram provided in an embodiment of the present invention for reading sub-circuit；

Fig. 4 is the equivalent circuit diagram of node control sub-circuit provided in an embodiment of the present invention；

Fig. 5 is the equivalent circuit diagram of light emitting control sub-circuit provided in an embodiment of the present invention；

Fig. 6 is the equivalent circuit diagram of pixel-driving circuit provided in an embodiment of the present invention；

Fig. 7 is the working timing figure of pixel-driving circuit provided in an embodiment of the present invention；

Fig. 8 A is working state figure of the pixel-driving circuit provided in an embodiment of the present invention in reset phase；

Fig. 8 B is working state figure of the pixel-driving circuit provided in an embodiment of the present invention in compensated stage；

Fig. 8 C is working state figure of the pixel-driving circuit provided in an embodiment of the present invention in the stage of reading；

Fig. 8 D is working state figure of the pixel-driving circuit provided in an embodiment of the present invention in light emitting phase；

Fig. 9 is the flow chart of the control method of pixel-driving circuit provided in an embodiment of the present invention.

Specific embodiment

To make the objectives, technical solutions, and advantages of the present invention clearer, below in conjunction with attached drawing to the present invention Embodiment be described in detail.It should be noted that in the absence of conflict, in the embodiment and embodiment in the application Feature can mutual any combination.

Step shown in the flowchart of the accompanying drawings can be in a computer system such as a set of computer executable instructions It executes.Also, although logical order is shown in flow charts, and it in some cases, can be to be different from herein suitable Sequence executes shown or described step.

Unless otherwise defined, the embodiment of the present invention discloses the technical term used or scientific term should be institute of the present invention The ordinary meaning that personage in category field with general technical ability is understood." first ", " second " used in the embodiment of the present invention And similar word is not offered as any sequence, quantity or importance, and be used only to distinguish different component parts. The similar word such as " comprising " or "comprising", which means to occur element or object before the word, to be covered to appear in and arranges behind the word The element of act perhaps object and its equivalent and be not excluded for other elements or object.The similar word such as " connection " or " connected " Language is not limited to physics or mechanical connection, but may include electrical connection, either direct or indirect 's.

The source electrode of the switching transistor used in all embodiments of the invention, drain electrode are symmetrically, so its source electrode, drain electrode It can be interchanged.In embodiments of the present invention, to distinguish the two poles of the earth of switching transistor in addition to grid, will wherein source electrode be known as First pole, drain electrode is known as the second pole, and grid is become control electrode.In addition, switching transistor used by the embodiment of the present invention It include: p-type switching transistor or two kinds of N-type switching transistor, wherein p-type switching transistor is low level conducting in grid, Grid ends when being high level, and N-type switching transistor is connected when grid is high level, ends when grid is low level.

Embodiment one

The embodiment of the present invention provides a kind of pixel-driving circuit, and Fig. 1 is pixel-driving circuit provided in an embodiment of the present invention Structural schematic diagram, as shown in Figure 1, pixel-driving circuit provided in an embodiment of the present invention is respectively with external control circuit (in figure It is not shown) it is connected with N number of light-emitting component, which includes: input sub-circuit, reads sub-circuit, node control Circuit and light emitting control sub-circuit, wherein N >=2.

Specifically, input sub-circuit, respectively with external control circuit, first node N1, reference signal end REF sum number it is believed that Number end DATA connection provides reference signal end REF to first node N1 or data is believed under the control of external control circuit Number end DATA signal；Sub-circuit is read, controls sub-circuit with outside respectively, first node N1 and reading signal end SENSE connect It connects, for reading the signal of first node N1 from reading signal end SENSE under the control of external control sub-circuit；Node control System circuit, respectively with first node N1, the first scanning end SCAN1, the second scanning end SCAN2, the first power end VDD, second Node N2 is connected with third node N3, for providing first node to second node N2 under the control of the first scanning end SCAN1 The signal of N1 provides the signal of first node N1 to third node N3 under the control of the second scanning end SCAN2；Light emitting control Sub-circuit, respectively with second node N2, third node N3, the first power end VDD, N number of light emitting control end EM1, EM2 ... EMN Connected with N number of light-emitting component, for second node N2, third node N3 and N number of light emitting control end EM1, EM2 ... EMN's Under control, N number of light-emitting component is driven to shine, wherein EMi indicates i-th of light emitting control end.

Specifically, pixel-driving circuit is arranged in OLED display panel, OLED display panel includes multiple pixel units, Each pixel unit is a light-emitting component, i.e., a pixel-driving circuit and multiple pixel units pair in the embodiment of the present invention It answers.

In the present embodiment, light emitting control end and light-emitting component are corresponded.It should be noted that due to OLED display panel Show the difference of content, N number of light-emitting component does not shine simultaneously, but successively shines.

In the present embodiment, the first power end VDD persistently provides high level signal, and reference signal end REF persistently provide reference Signal such as voltage value is the signal of 0V, i.e. reference signal end REF can be ground terminal.It should be noted that external control electricity Road can also provide letter to reference signal end REF, data signal end DATA, the first scanning end SCAN1 and the second scanning end SCAN1 Number, to control the input of reference signal end REF, data signal end DATA, the first scanning end SCAN1 and the second scanning end SCAN2 Signal.

Pixel-driving circuit provided in an embodiment of the present invention is connect with external control circuit and N number of light-emitting component respectively, as Plain driving circuit includes: input sub-circuit, reads sub-circuit, node control sub-circuit and light emitting control sub-circuit, N >=2；Input Sub-circuit is connect with external control circuit, first node, reference signal end and data signal end respectively, for controlling in outside Under the control of circuit, the signal of reference signal end or data signal end is provided to first node；Read sub-circuit, respectively with outside It controls sub-circuit, first node and reads signal end and connect, under the external control for controlling sub-circuit, from reading signal end Read the signal of first node；Node control sub-circuit, respectively with first node, the first scanning end, the second scanning end, first electricity Source, second node are connected with third node, for providing first node to second node under the control of the first scanning end Signal provides the signal of first node to third node under the control of the second scanning end；Light emitting control sub-circuit, respectively with Second node, third node, the first power end, N number of light emitting control end are connected with N number of light-emitting component, in second node, the Under the control at three nodes and N number of light emitting control end, N number of light-emitting component is driven to shine, light emitting control end and light-emitting component one are a pair of It answers.Pixel-driving circuit provided in an embodiment of the present invention is connect with a plurality of light-emitting elements, to drive a plurality of light-emitting elements to shine, energy The quantity of component in pixel-driving circuit in OLED display panel is enough reduced, and then the pixel for promoting OLED display panel is close Degree.

Optionally, light-emitting component can be Organic Light Emitting Diode OLED, specifically, the sun of Organic Light Emitting Diode OLED Pole is connect with light emitting control sub-circuit, and cathode is connect with second source end VSS.

In the present embodiment, second source end VSS persistently provide low level signal.

Optionally, Fig. 2 is the equivalent circuit diagram of input sub-circuit provided in an embodiment of the present invention, as shown in Fig. 2, of the invention The input sub-circuit that embodiment provides includes: first switch SW1 and second switch SW2, first switch SW1 and second switch SW2 It is opened or closed by external control circuit control.

Specifically, the first end of first switch SW1 is connect with reference signal end REF, second end and first node N1 connect It connects；The first end of second switch SW2 is connect with data signal end DATA, and second end is connect with first node N1.

In the present embodiment, data signal end DATA and the public conducting wire of reference signal end REF reduce wiring, into one Improve the pixel density of OLED display panel to step.

It should be noted that the exemplary structure of input sub-circuit has been shown in particular in Fig. 2, those skilled in the art are easy reason Solution, the implementation of the sub-circuit is not limited to this, as long as can be realized its function.

Optionally, Fig. 3 is the equivalent circuit diagram provided in an embodiment of the present invention for reading sub-circuit, as shown in figure 3, of the invention The reading sub-circuit that embodiment provides includes: third switch SW3, and third switch SW3 is controlled by external control circuit and disconnected or close It closes.

Specifically, the first end of third switch SW3 is connect with signal end SENSE is read, second end and first node N1 Connection.

It should be noted that the exemplary structure for reading sub-circuit has been shown in particular in Fig. 3, those skilled in the art are easy reason Solution, the implementation of the sub-circuit is not limited to this, as long as can be realized its function.

Optionally, Fig. 4 is the equivalent circuit diagram of node control sub-circuit provided in an embodiment of the present invention, as shown in figure 4, this The node control sub-circuit that inventive embodiments provide includes: first switch transistor M1, second switch transistor M2, first capacitor C1 and the second capacitor C2.

Specifically, the control electrode of first switch transistor M1 is connect with the first scanning end SCAN1, the first pole and first segment Point N1 connection, the second pole is connect with second node N2；The control electrode of second switch transistor M2 and the second scanning end SCAN2 connect It connects, the first pole is connect with first node N1, and the second pole is connect with third node N3；The first end of first capacitor C1 and second Node N2 connection, second end are connect with the first power end VDD；The first end of second capacitor C2 is connect with second node N2, Second end is connect with third node N3.

It should be noted that the exemplary structure of node control sub-circuit has been shown in particular in Fig. 4, those skilled in the art hold Intelligible to be, the implementation of the sub-circuit is not limited to this, as long as can be realized its function.

Optionally, Fig. 5 is the equivalent circuit diagram of light emitting control sub-circuit provided in an embodiment of the present invention, such as

Shown in Fig. 5, light emitting control sub-circuit provided in an embodiment of the present invention includes: driving transistor DTFT and third switch Transistor M3~N+2 switching transistor MN+2.

Specifically, the control electrode of driving transistor DTFT is connect with second node N2, source electrode is connect with third node N3, Its drain electrode is connect with the first power end VDD；The control electrode of i-th switching transistor Mi is connect with the i-th -2 light emitting control ends, the One pole is connect with third node N3, the sun of the second pole Organic Light Emitting Diode OLED corresponding with the i-th -2 light emitting control ends Pole connection, 3≤i≤N+2.

By taking N=2 as an example, the control electrode of third switching transistor M3 is connect with first light emitting control end EM1, the second pole It is connect with the anode of first Organic Light Emitting Diode OLED1, the control electrode of the 4th switching transistor M4 and second control that shines EM2 connection in end processed, the second pole are connect with the anode of second Organic Light Emitting Diode OLED2, it should be noted that N may be used also Think other numerical value for being greater than 2, the embodiment of the present invention is not limited in any way this.

It should be noted that the exemplary structure of light emitting control sub-circuit has been shown in particular in Fig. 5, those skilled in the art hold Intelligible to be, the implementation of the sub-circuit is not limited to this, as long as can be realized its function.

Optionally, the driving transistor DTFT in the present embodiment can be enhancement transistor or depletion mode transistor, Here this is not especially limited.

Fig. 6 is the equivalent circuit diagram of pixel-driving circuit provided in an embodiment of the present invention, as shown in fig. 6, pixel driver is electric Road includes: input sub-circuit, reads sub-circuit, node control sub-circuit and light emitting control sub-circuit, wherein input sub-circuit, It include: first switch SW1 and second switch SW2；Reading sub-circuit includes: third switch SW3；Node control sub-circuit includes: First switch transistor M1, second switch transistor M2, first capacitor C1 and the second capacitor C2；Light emitting control sub-circuit includes: Drive transistor DTFT and third switching transistor M3~N+2 switching transistor MN+2.

Specifically, the first end of first switch SW1 is connect with reference signal end REF, second end and first node N1 connect It connects；The first end of second switch SW2 is connect with data signal end DATA, and second end is connect with first node N1；Third switch The first end of SW3 is connect with signal end SENSE is read, and second end is connect with first node N1；First switch transistor M1's Control electrode is connect with the first scanning end SCAN1, and the first pole is connect with first node N1, and the second pole and second node N2 connect It connects；The control electrode of second switch transistor M2 is connect with the second scanning end SCAN2, and the first pole is connect with first node N1, Second pole is connect with third node N3；The first end of first capacitor C1 is connect with second node N2, second end and the first power supply Hold VDD connection；The first end of second capacitor C2 is connect with second node N2, and second end is connect with third node N3；Driving is brilliant The control electrode of body pipe DTFT is connect with second node N2, and source electrode is connect with third node N3, drain electrode and the first power end VDD Connection；The control electrode of i-th switching transistor Mi is connect with the i-th -2 light emitting control end EM, and the first pole and third node N3 connect It connects, the light-emitting component connection corresponding with the i-th -2 light emitting control ends of the second pole, 3≤i≤N+2.

In the present embodiment, optionally, outside control sub-circuit is also used to the signal according to first node N1, and it is brilliant to obtain driving The threshold voltage vt h of body pipe DTFT, and offset voltage is obtained according to threshold voltage, it is also used to provide benefit to data signal end DATA Voltage is repaid, so that pixel-driving circuit compensates driving transistor according to offset voltage.

In the present embodiment, switching transistor M1~MN+2 all can be N-type TFT or P-type TFT, It can unify process flow, manufacturing process can be reduced, help to improve the yield of product.In addition, it is contemplated that low temperature polycrystalline silicon The leakage current of thin film transistor (TFT) is smaller, and therefore, preferably all transistors of the embodiment of the present invention are low-temperature polysilicon film transistor, Thin film transistor (TFT) specifically can choose the thin film transistor (TFT) of bottom grating structure or the thin film transistor (TFT) of top gate structure, as long as can be real Existing switching function.

It is N-type film crystal with switching transistor M1~MN+2 in pixel-driving circuit provided in an embodiment of the present invention For pipe, Fig. 7 is the working timing figure of pixel-driving circuit provided in an embodiment of the present invention, and Fig. 8 A provides for the embodiment of the present invention Pixel-driving circuit reset phase working state figure；Fig. 8 B is that pixel-driving circuit provided in an embodiment of the present invention is being mended Repay the working state figure in stage；Fig. 8 C is working condition of the pixel-driving circuit provided in an embodiment of the present invention in the stage of reading Figure；Fig. 8 D is working state figure of the pixel-driving circuit provided in an embodiment of the present invention in light emitting phase.As can be seen from figures 6 to 8, originally Pixel-driving circuit involved in inventive embodiments includes: N+2 switching transistor (M1~MN+2), 1 driving transistor (DTFT), 2 capacitor cells (C1 and C2), N+4 input terminal (DATA, REF, SCAN1, SCAN2, EM1, EM2 ..., EMN), 1 reading end (SENSE) and 2 power ends (VDD and VSS).

Specifically, the first power end VDD persistently provides high level signal, second source end VSS persistently provides low level letter Number, reference signal end REF persistently provide reference signal, wherein the voltage of reference signal is 0V.

Specifically:

First stage S1, i.e. reset phase, in conjunction with Fig. 7 and Fig. 8 A, external control circuit opens first switch SW1, to the The signal of the signal of one node N1 offer reference signal end REF, the first scanning end SCAN1 and the second scanning end SCAN2 are high electricity Flat, first switch transistor M1 and second switch transistor M2 are connected, and the signal of second node N2 and third node N3 are by first The signal of node N1 is reset.

Second stage S2, i.e. compensated stage, in conjunction with Fig. 7 and Fig. 8 B, external control circuit disconnects first switch SW1, closure Second switch SW2 provides the signal of data signal end DATA to first node N1, wherein the signal of data signal end DATA Voltage value is V0, and the signal of the first scanning end SCAN1 is high level, first switch transistor M1 conducting, the letter of second node N2 It number is drawn high by the signal of first node N1, since the difference of the current potential of second node N2 and third node N3 is greater than driving transistor The threshold voltage vt h of DTFT, therefore, driving transistor DTFT conducting, the first power end VDD charge to third node N3, until The voltage value of the signal of third node N3 is equal to V0-Vth, driving transistor DTFT cut-off, at this point, storing electricity in the second capacitor C2 Amount is Vth.

Phase III S3, i.e. reading stage, in conjunction with Fig. 7 and Fig. 8 C, external control circuit disconnects second switch SW2, closure The signal of third switch SW3, the second scanning end SCAN2 are high level, second switch transistor M2 conducting, external control circuit control System reads the signal that signal end SENSE reads third node N3, to obtain the threshold voltage vt h of driving transistor DTFT.

Fourth stage S4, i.e. light emitting phase, in conjunction with Fig. 7 and Fig. 8 D, external control circuit disconnects third switch SW3, closure Second switch SW2 provides the signal V1 of data signal end DATA to first node N1, specifically, light emitting phase includes: timesharing hair N number of sub- light emitting phase of light, wherein i-th of sub- light emitting phase is corresponding with i-th of Organic Light Emitting Diode OLEDi, i.e., and i-th I-th of organic light-emitting diode OLEDi shines in sub- light emitting phase, 1≤i≤N, specifically, every sub- light emitting phase packet It includes: the first sub-stage and the second sub-stage, specific:

First sub-stage, the signal of the first scanning end SCAN1 are high level, first switch transistor M1 conducting, to second Node N2 provides the signal of first node N1, since the difference of the current potential of second node N2 and third node N3 is greater than driving transistor The threshold voltage vt h of DTFT, therefore, driving transistor DTFT conducting, but due to i-th OLEDi pairs of Organic Light Emitting Diode The signal of the light emitting control end EMi answered is low level, and therefore, i-th of Organic Light Emitting Diode OLEDi does not shine.

Second sub-stage, the signal of the first scanning end SCAN1 are low level, first switch transistor M1 cut-off, first Under the action of capacitor C1 bootstrapping, driving transistor DTFT conducting, the corresponding light emitting control of i-th of Organic Light Emitting Diode OLEDi The signal for holding EMi is high level, and therefore, i-th of Organic Light Emitting Diode OLEDi shines.

It should be noted that the signal V1 of data signal end DATA is different when different organic light-emitting diode.

In the present embodiment, in every sub- light emitting phase, the data-signal of data signal end DATA is external control circuit root It is obtained according to threshold voltage, in light emitting phase, inputs the data-signal to the control electrode of driving transistor DTFT, it can be organic When light emitting diode OLED shines, threshold voltage compensation is carried out to driving transistor DTFT, guarantees the uniformity of display, improves Display effect.

Pixel-driving circuit driving a plurality of light-emitting elements provided in an embodiment of the present invention and a picture in the related technology Plain driving circuit drives a light-emitting component to compare, and when the light-emitting component quantity of luminescence display is identical, the embodiment of the present invention is mentioned Only one driving transistor is compensated in compensated stage for technical solution, the compensation time is reduced to benefit in the related technology Repay the 1/N of time.

Embodiment two

Inventive concept based on the above embodiment, the embodiment of the present invention also provide a kind of controlling party of pixel-driving circuit Method, Fig. 9 is the flow chart of the control method of pixel-driving circuit provided in an embodiment of the present invention, as shown in figure 9, the present invention is implemented Example provide pixel-driving circuit driving method specifically includes the following steps:

Step 100, input sub-circuit provide the signal at reference signal end to first node, and node control sub-circuit is first Under the control of scanning end, the signal for providing first node to second node is mentioned under the control of the second scanning end to third node For the signal of first node.

Step 200, input sub-circuit provide the signal of data signal end to first node, and node control sub-circuit is first Under the control of scanning end, the signal of first node is provided to second node.

Step 300, node control sub-circuit provide the letter of third node under the control of the second scanning end, to first node Number, sub-circuit is read under the control of external control sub-circuit, from the signal for reading signal end reading first node.

Step 400, node control sub-circuit provide the letter of first node under the control of the first scanning end, to second node Number, light emitting control sub-circuit is used under the control of second node, third node and N number of light emitting control end, drives N number of luminous member Part shines.

Wherein, pixel-driving circuit is the pixel-driving circuit that embodiment one provides, realization principle and realization effect class Seemingly, details are not described herein.

Optionally, before step 400, outside control sub-circuit is also used to the signal according to first node, is driven The threshold voltage of transistor, and offset voltage is obtained according to threshold voltage, it is also used to provide offset voltage to data signal end, with So that pixel-driving circuit compensates driving transistor according to offset voltage in light emitting phase.

Embodiment three

Inventive concept based on the above embodiment, the embodiment of the present invention also provide a kind of display device, the embodiment of the present invention The display device of offer includes: pixel-driving circuit.

Optionally, which can be with are as follows: mobile phone, tablet computer, television set, display, laptop, digital phase Any products or components having a display function such as frame, navigator.

Attached drawing of the embodiment of the present invention is pertained only to the present embodiments relate to the structure arrived, and other structures, which can refer to, usually to be set Meter.

In the absence of conflict, the feature in the embodiment of the present invention, that is, embodiment can be combined with each other new to obtain Embodiment.

Although disclosed herein embodiment it is as above, the content only for ease of understanding the present invention and use Embodiment is not intended to limit the invention.Technical staff in any fields of the present invention is taken off not departing from the present invention Under the premise of the spirit and scope of dew, any modification and variation, but the present invention can be carried out in the form and details of implementation Scope of patent protection, still should be subject to the scope of the claims as defined in the appended claims.

Claims

1. A pixel drive circuit, characterized in that it is respectively connected with an external control circuit and N light-emitting elements, and the pixel drive circuit comprises: an input subcircuit, a readout subcircuit, a node control subcircuit and a light emission control subcircuit, N≥2;

The input sub-circuit is respectively connected with the external control circuit, the first node, the reference signal terminal and the data signal terminal, and is used for providing the first node with a signal of the reference signal terminal or the data signal terminal under the control of the external control circuit;

The reading sub-circuit is respectively connected with the external control sub-circuit, the first node and the reading signal terminal, and is used for reading the signal of the first node from the reading signal terminal under the control of the external control sub-circuit;

The node control sub-circuit is respectively connected with the first node, the first scan end, the second scan end, the first power supply end, the second node and the third node, and is used for, under the control of the first scan end, to the second The node provides the signal of the first node, and under the control of the second scanning terminal, provides the signal of the first node to the third node;

The light-emitting control sub-circuit is respectively connected with the second node, the third node, the first power supply terminal, the N light-emitting control terminals and the N light-emitting elements, and is used for the connection between the second node, the third node and the N light-emitting control terminals. Under the control, N light-emitting elements are driven to emit light, and the light-emitting control terminals are in one-to-one correspondence with the light-emitting elements.

2 . The pixel driving circuit according to claim 1 , wherein the input sub-circuit comprises: a first switch and a second switch, and the first switch and the second switch are controlled by the external control circuit. 3 . open or close;

The first end of the first switch is connected to the reference signal end, and the second end of the first switch is connected to the first node;

The first end of the second switch is connected to the data signal end, and the second end of the second switch is connected to the first node.

3 . The pixel driving circuit according to claim 1 , wherein the reading sub-circuit comprises: a third switch, and the third switch is controlled to be opened or closed by the external control circuit; 3 .

The first end of the third switch is connected to the read signal end, and the second end of the third switch is connected to the first node.

4. The pixel driving circuit according to claim 1, wherein the node control sub-circuit comprises: a first switch transistor, a second switch transistor, a first capacitor and a second capacitor;

The control electrode of the first switching transistor is connected to the first scanning terminal, the first electrode is connected to the first node, and the second electrode is connected to the second node;

The control electrode of the second switching transistor is connected to the second scanning terminal, the first electrode is connected to the first node, and the second electrode is connected to the third node;

The first end of the first capacitor is connected to the second node, and the second end of the first capacitor is connected to the first power supply end;

The first end of the second capacitor is connected to the second node, and the second end of the second capacitor is connected to the third node.

5 . The pixel driving circuit according to claim 1 , wherein the light-emitting element is an organic light-emitting diode, and the anode of the organic light-emitting diode is connected to the light-emitting control sub-circuit, and the cathode of the organic light-emitting diode is connected to the second power terminal. 6 . .

6 . The pixel driving circuit according to claim 5 , wherein the light emission control sub-circuit comprises: a driving transistor and a third switching transistor to an N+2 th switching transistor; 6 .

The control electrode of the driving transistor is connected to the second node, the source electrode is connected to the third node, and the drain electrode is connected to the first power supply terminal;

The control electrode of the i-th switching transistor is connected to the i-2th light-emitting control terminal, its first electrode is connected to the third node, and its second electrode is connected to the anode of the organic light-emitting diode corresponding to the i-2th light-emitting control terminal, 3≤i≤N+2.

7 . The pixel driving circuit according to claim 1 , wherein the input sub-circuit comprises: a first switch and a second switch; the reading sub-circuit comprises: a third switch; the node control sub-circuit It includes: a first switch transistor, a second switch transistor, a first capacitor and a second capacitor; the light-emitting control sub-circuit includes: a drive transistor and a third switch transistor to an N+2th switch transistor;

The first end of the second switch is connected to the data signal end, and the second end of the second switch is connected to the first node;

The first end of the third switch is connected to the read signal end, and the second end of the third switch is connected to the first node;

The first end of the second capacitor is connected to the second node, and the second end of the second capacitor is connected to the third node;

The control electrode of the i-th switching transistor is connected to the i-2th light-emitting control terminal, its first electrode is connected to the third node, and its second electrode is connected to the light-emitting element corresponding to the i-2th light-emitting control terminal, 3≤i ≤N+2.

8. The pixel driving circuit according to claim 7, wherein the external control sub-circuit is further configured to obtain the threshold voltage of the driving transistor according to the signal of the first node, and obtain the compensation voltage according to the threshold voltage, and further use The compensation voltage is provided to the data signal terminal, so that the pixel driving circuit compensates the driving transistor according to the compensation voltage.

9 . A control method for a pixel driving circuit, wherein, when applied to the pixel driving circuit according to any one of claims 1 to 8 , the method comprises: 10 .

The input sub-circuit provides the signal of the reference signal terminal to the first node, the node control sub-circuit provides the signal of the first node to the second node under the control of the first scanning terminal, and provides the first node to the third node under the control of the second scanning terminal. A node's signal;

The input subcircuit provides the signal of the data signal terminal to the first node, and the node control subcircuit provides the signal of the first node to the second node under the control of the first scanning terminal;

The node control subcircuit provides the first node with the signal of the third node under the control of the second scanning terminal, and the reading subcircuit reads the signal of the first node from the reading signal terminal under the control of the external control subcircuit;

The node control sub-circuit provides the signal of the first node to the second node under the control of the first scanning terminal, and the light-emitting control sub-circuit is used to drive N light-emitting devices under the control of the second node, the third node and the N light-emitting control terminals Component glows.

10. A display device, comprising: the pixel driving circuit according to any one of claims 1 to 8.