CN103077683A - Driving circuit of active-matrix organic light-emitting diode (AMOLED) panel and corresponding driving method - Google Patents

Abstract

The invention discloses a driving circuit of an active-matrix organic light-emitting diode (AMOLED) panel. The driving circuit of the AMOLED panel comprises a driving assembly and a sub-pixel cell. The driving assembly comprises a scanning pin and a data pin; the sub-pixel cell comprises sub-pixel lines and sub-pixel columns; the sub-pixel lines respectively comprise sub-pixels of all pixels belonging to the same line, wherein the sub-pixels are same in emitting color; data signal input ends of all the sub-pixels in each sub-pixel line are connected together and are mutually connected with the data pin of the driving element; and scanning signal input ends of all the sub-pixels in each sub-pixel column are connected together and are mutually connected with the scanning pin of the driving element. Through improvements, red-green-blue (RGB) sub-pixels are distinguished from each other when panel sub-pixels are connected by the driving circuit disclosed by the invention, so that the driving of the AMOLED panel adopting the driving circuit does not need to adopt an RGB data signal multiplexing mode. Further, a necessary demultiplexing module adopting a traditional driving circuit can be saved on a hardware circuit, so that the product complexity and cost are reduced.

Description

A kind of driving circuit of AMOLED panel and corresponding driving method

Technical field

The present invention relates to AMOLED display technique field, be specifically related to a kind of AMOLED panel drive circuit and the driving method corresponding with this driving circuit.

Background technology

In flat panel display, many merits such as display is frivolous with it for Organic Light Emitting Diode (Organic Light-Emitting Diode, OLED), active illuminating, fast-response speed, wide viewing angle, rich color and high brightness, low-power consumption, high-low temperature resistant and to be known as by industry be third generation display technique after liquid crystal display (LCD).Active OLED(Active Matrix OLED, AMOLED) be also referred to as active matrix OLED, AMOLED drives by integrated thin-film transistor (TFT) and capacitor in each pixel and by the method that capacitor is kept voltage, can realize large scale, resolution panels, be the emphasis of current research and the developing direction of following display technique.

The basic pixel circuit structure of AMOLED is 2T1C structure shown in Figure 1, and basic pixel circuit specifically is comprised of switching transistor T1, driving transistors T2 and memory capacitance Cs.Wherein, the grid of switching transistor T1 is connected with data line Vdata with sweep trace Vscan respectively with source electrode, the drain electrode of switching transistor T1 is connected with the grid of driving transistors T2, the source electrode connecting power line Vdd of driving transistors T2, drain electrode is connected with light emitting diode OLED, another utmost point ground connection of OLED, described memory capacitance C one end connecting power line Vdd, the other end is connected with the common port of driving transistors T2 with switching transistor T1.Image element circuit domain (layout at the AMOLED panel, be the space structure relation of pixel element such as OLED, T1, T2 and Cs) in, the organic material district of Organic Light Emitting Diode OLED occupies pixel region except the certain area beyond the driving circuit, and the number percent that in the industry organic material district of OLED is accounted for elemental area is defined as the aperture opening ratio of OLED.In the performance index of estimating AMOLED, aperture opening ratio is an important indicator.Specifically, the raising of aperture opening ratio can bring that panel driving current reduction, power consumption diminish, the series of advantages such as brightness increase and ILS.

Suppose that piece image is the capable N row of M (be calculated as the 3N row by the RBG sub-pixel, the demultiplexing of RGB is realized in drive IC), the existing scan method of AMOLED panel is to scan line by line from top to bottom, and corresponding image shows it also is to show line by line from top to bottom therewith.That is to say, scan first the 1st row (inputting simultaneously a 3N row pixel data signal of the 1st row), scan again the 1st row (inputting simultaneously a 3N row pixel data signal of the 2nd row), until M capable (inputting simultaneously the capable 3N row pixel data signal of M).Wherein primitive shape is square, and it is 3 times of width that each sub-pixel is its length of list structure.

Existing driving circuit is shown in Fig. 3 a, comprise pixel column L, pixel column S and driver element, pixel column L comprises the whole RGB sub-pixels that belong to all pixels of delegation, pixel column S comprises the sub-pixel that the glow color of all pixels that belong to same row is identical, and driver element comprises data terminal and scanning end.For example the first pixel column L1 comprises all RGB sub-pixels of the first row, and the second pixel column L2 comprises all RGB sub-pixels of the second row; The first pixel column S1R comprises all R sub-pixels of first row pixel, and the second pixel column S1G comprises all G sub-pixels of first row pixel.Wherein, the data-signal input end of all pixel columns links together and is connected with the driver element data terminal, be used for to the sub-pixel input data signal, the sweep signal input end of all pixel columns links together and is connected with the scanning end of driver element, is used for to sub-pixel input scan signal.Adopt the driving process of the AMOLED panel of this driving circuit to be: at first addressing L1 is capable, and L1 is capable, and all RGB sub-pixels are all chosen simultaneously; Then addressing L2 is capable, and L2 is capable, and all RGB sub-pixels are all chosen simultaneously; Constantly repeat, until addressing L320 is capable, L320 is capable, and all RGB sub-pixels are all chosen simultaneously; Finish thus the scanning of a hardwood picture.

Existing this AMOLED panel drive circuit is the form that generally adopts at present, wherein data-signal be input as the RGB multiplexed form, need in driver element inside or panel, increase RGB data demultiplexing circuit module.

In the performance index of estimating AMOLED, aperture opening ratio is an important indicator.Specifically, the raising of aperture opening ratio can bring that the panel driving current density reduces, driving voltage reduces, power consumption reduces, the series of advantages such as brightness raising and life.

But can find out from image element circuit structure, data signal line Vdata and power lead Vdd (are respectively the source electrode of T1, T2) in same plane, all at the long side direction of sub-pixel, are unfavorable for the raising of pixel aperture ratio.In addition, because the existence of array inner lead resistance is so that the IR-DROP(resistance drop of Vdd) comparatively serious, for reducing the IR-DROP of supply voltage Vdd, generally power lead Vdd need to be designed much widelyr than data line Vdata and addressed line Vscan, further affect especially pixel aperture ratio.

Summary of the invention

The present invention proposes a kind of AMOLED panel drive circuit and method thereof, to save the RGB data demultiplexing circuit module that adopts existing drives in driver element inside or panel, to increase.

Technical scheme of the present invention is: a kind of AMOLED panel drive circuit, comprise driver element and sub-pixel unit, driver element comprises scanning pin and data pin, sub-pixel unit comprises rows and sub-pixel column, rows comprises the identical sub-pixel of glow color that belongs to all pixels of delegation, and sub-pixel column comprises whole RGB sub-pixels of all pixels that belong to same row; It is characterized in that, the data-signal input end of all sub-pixels of described rows links together and is connected with the data pin of driver element, and the sweep signal input end of all sub-pixels of sub-pixel column links together and is connected with the scanning pin of driver element.

The AMOLED panel driving method that a kind of and above-mentioned driving circuit is corresponding may further comprise the steps:

A, addressing the first rows: all R sub-pixels of the first row pixel are all chosen simultaneously, input simultaneously the data-signal of this rows;

B, addressing next son pixel column: this sub-pixel is all chosen simultaneously, inputs simultaneously the data-signal of this rows;

C, repeating step b return step a after the to the last data-signal of rows input is finished, and enter simultaneously the addressing of next frame cycle.

The present invention is by the data-signal input end of change ranks pixel and the annexation of sweep signal input end, and the data-signal input end of the sub-pixel that glow color is identical links together.Because the present invention is about to the RGB sub-pixel area and separates when the panel sub-pixel connects, so adopt the driving of the AMOLED panel of this driving circuit to need not the form that adopts the RGB data-signal multiplexing, further on hardware circuit, can save and adopt the necessary demultiplexing module of existing driving circuit, reduce product complexity and cost.

Description of drawings

Fig. 1 is the pixel-driving circuit figure of AMOLED panel of the present invention;

Fig. 2 a is the structural representation after the manufacturing process steps 1 of AMOLED panel pixel circuit layout of the present invention;

Fig. 2 b is the structural representation after the manufacturing process steps 2 of AMOLED panel pixel circuit layout of the present invention;

Fig. 2 c is the structural representation after the manufacturing process steps 3 of AMOLED panel pixel circuit layout of the present invention;

Fig. 2 d is the structural representation after the manufacturing process steps 4 of AMOLED panel pixel circuit layout of the present invention;

Fig. 2 e is the structural representation after the manufacturing process steps 5 of AMOLED panel pixel circuit layout of the present invention;

Fig. 2 f is the structural representation after the manufacturing process steps 6 of AMOLED panel pixel circuit layout of the present invention;

Fig. 2 g is the structural representation after the manufacturing process steps 7 of AMOLED panel pixel circuit layout of the present invention;

Fig. 3 a is the structural representation of existing AMOLED panel sweep circuit;

Fig. 3 b is the structural representation of AMOLED panel sweep circuit of the present invention.

Embodiment

Below in conjunction with drawings and Examples principle of the present invention is further described.

A kind of AMOLED panel drive circuit of the present invention is shown in Fig. 3 b, comprise driver element and sub-pixel unit, driver element comprises scanning pin and data pin, sub-pixel unit comprises rows L and sub-pixel column S, rows L comprises the identical sub-pixel of glow color that belongs to all pixels of delegation, and sub-pixel column S comprises whole RGB sub-pixels of all pixels that belong to same row; For example the first rows L1R comprises all R sub-pixels of the first row, and the second rows L1G comprises all G sub-pixels of the first row; The first sub-pixel column S1 comprises all RGB sub-pixels of first row pixel, and the second sub-pixel column S1 comprises all RGB sub-pixels of secondary series pixel.The data-signal input end of all sub-pixels of described rows L links together and is connected with the data pin of driver element, and the sweep signal input end of all sub-pixels of sub-pixel column links together and is connected with the scanning pin of driver element.Adopt the advantage of this connected mode be arbitrary data line corresponding be the single sub-pixel unit of glow color, so need not the data mode that adopts RGB multiplexing, also the RGB demultiplexing unit need not be set.

In order to realize that the AMOLED panel scans in above-described embodiment to adopting, a kind of AMOLED panel driving method is provided in the present embodiment, specifically may further comprise the steps:

A, addressing the first rows: all R sub-pixels of the first row pixel are all chosen simultaneously, input simultaneously the data-signal of this rows;

B, addressing next son pixel column: this sub-pixel is all chosen simultaneously, inputs simultaneously the data-signal of this rows;

C, repeating step b return step a after the to the last data-signal of rows input is finished, and enter simultaneously the addressing of next frame cycle.

The characteristics of this embodiment are the sub-pixel unit of different glow colors is adopted the respectively method of input data signal, avoided like this data input form of RGB data-reusing, the demultiplexing circuit module that originally must adopt can be saved, driving circuit is simplified.

Further promote for the performance that makes the AMOLED panel is whole, the driving circuit of the AMOLED panel in above-described embodiment and driving method can use simultaneously with following AMOLED panel pixel layout design: a kind of AMOLED panel pixel circuit layout as Fig. 2 g is depicted as the present embodiment comprises RGB strip sub-pixel, switching transistor T21, driving transistors T22, sweep trace Vscan2, data line Vdata2, power lead Vdd2, memory capacitance C2 and Organic Light Emitting Diode OLED; Wherein, sweep trace Vscan2 distributes along strip sub-pixel long side direction in the image element circuit domain, data line Vdata2 and power lead Vdd2 distribute along strip sub-pixel short side direction in the image element circuit domain, and the outer parallel with sweep trace Vscan2, organic material evaporation zone of Organic Light Emitting Diode OLED is respectively the edge of sweep trace Vscan2 and place sub-pixel; In the present embodiment, circuit component (elements such as transistor and memory capacitance) and connecting line (sweep trace, the connecting line such as data line and power lead) ohm annexation between does not change, that is: the grid of switching transistor T21 is connected with data line Vdata2 with sweep trace Vscan2 respectively with source electrode, the drain electrode of switching transistor T1 is connected with the grid of driving transistors T22, the source electrode connecting power line Vdd2 of driving transistors T22, drain electrode is connected with light emitting diode OLED, another utmost point ground connection of OLED, described memory capacitance C2 one end connecting power line Vdd2, the other end is connected with the common port of driving transistors T22 with switching transistor T21.

Above-mentioned AMOLED panel also comprises the capable N row of the M pixel that is the matrix arrangement, further, and M=320, N=240; Each pixel comprises R, G, three sub-pixels of B, all sub-pixels that belong to delegation's pixel are a data unit, totally 320 data unit belong to same row and OLED luminous for all sub-pixels of same color are a scanning element, altogether 240*3=720 scanning element; The data line Vdata2 of all sub-pixels of same data cell interconnects, and obtains altogether 320 data terminals, and the sweep trace Vscan2 of all sub-pixels of same scanning element interconnects, and obtains altogether 720 scanning ends.

Switching transistor T21 is " Contraband " shape in above-mentioned arbitrary embodiment, and its purpose has enough spaces when being to make sweep trace Vscan, data line Vdata and the conversion of power lead Vdd procession, keeps simultaneously original circuit connection structure constant.

Shown in Fig. 2 a-Fig. 2 g, for the technical scheme of the image element circuit domain that can easierly understand the present embodiment, in following examples, provide a kind of concrete manufacture craft of described image element circuit domain, the steps include:

Step 1(Layer1): shown in Fig. 2 a, oxide buffer layer (Buffer Oxide Layer) at glass substrate is made active layer (Active) pattern, method is to form amorphous silicon (a-Si) film after forming oxide buffer layer (Buffer Oxide Layer), evaporation Capping Layer more afterwards, then evaporation Ni and carry out pre-service, form again polysilicon membrane, until form the Active pattern.Active layer pattern in this step is different from existing active layer pattern, switching transistor pattern T21 in the active layer pattern in this step is " Contraband " font, the design of this " Contraband " font is different from the design of existing " second " font, and its purpose is the vertical layout outflow space into sweep trace in the image element circuit domain.

Step 2(Layer2): shown in Fig. 2 b, after evaporation gate insulator (Gate Insulator) and gate metal layer (Gate Metal), carry out simultaneously etching, Gate Metal implements wet etching (Wet Etching), afterwards Gate Insulator is carried out dry etching (Dry Etching), form the Gate layer pattern, formed in this step the sweep trace of vertical layout.

Step 3(Layer3): shown in Fig. 2 c, after step 2 formed the Gate layer, ILD (the Inter Layer Dielectric) film of coating insulation by VIA1 technique, reserved contact hole 21 afterwards.

Step 4(Layer4): shown in Fig. 2 d, evaporation METAL layer, the contact hole 21 that stays by step 3 is connected with ACT and Gate layer, finishing pixel-driving circuit is connected with data line with external power source and is connected, and in pixel inside the drain electrode of switching tube linked to each other with the grid of driving tube and to form simultaneously the memory capacitance of pixel-driving circuit, formed in this step data line and the power lead of lateral arrangement.

Step 5(Layer5): shown in Fig. 2 e; TFT and metal wire for better protection bottom; after step 4, will form passivation layer (Passivation Layer), then get the connecting hole 22 of drain D and OLED positive pole in Passivation Layer punching as driving tube.

Step 6(Layer6): shown in Fig. 2 f, finish the making of OLED transparent anode (IZO) 23, and link to each other with the driving tube drain D by the contact hole that step 5 stays.

Step 7(Layer7): shown in Fig. 2 g, adopt insulating resin coating panel, then etching only reserves OLED part 24 and carries out follow-up organic material evaporation, in this step, organic material evaporation district is extending transversely and occupied the panel space that the vertical power lead that distributes of script occupies, and makes the longitudinal edge in organic material evaporation district along the edge that extends to sweep trace Vscan and the place sub-pixel of vertical distribution.Need to prove that said organic material evaporation district longitudinal edge is to carry out along extension here under the prerequisite of design rule, that is to say take sweep trace Cscan not refer to as the edge contact fully with sweep trace, and refer to and sweep trace between keep a design rule the interval.

Below in conjunction with embodiment effect of the present invention is further analyzed, suppose that power lead Vdd live width is that 14um, data line Vdata and sweep trace Vscan live width are 7um, design rule is 4um, and the breadth length ratio of TFT is 7um/19um, and sub-pixel size is 55um*165um.Image element circuit domain in the embodiments of the invention is shown in Fig. 2 g, and be different from traditional composition: 1, sweep trace Vscan is parallel to the sub-pixel direction by changing into perpendicular to the sub-pixel direction, and is namely vertical; 2, data line Vdata and power lead Vdd change into perpendicular to the sub-pixel direction by being parallel to the sub-pixel direction, and be namely horizontal; 3, the luminous organic material evaporation area width of sub-pixel increases, and takes the space after power lead Vdd removes.Usefulness of the present invention has been to increase the luminous organic material evaporation area of sub-pixel, has improved the panel aperture opening ratio.Analyze from single sub-pixel: in the prior art, the width of organic material deposition unit is 55-7-4-4-14-4=22 to the maximum; In the present embodiment, organic material deposition unit width is 55-7-4-4=40 to the maximum, and the amplitude that aperture opening ratio improves is

According to the JVL curve characteristic of each luminous organic material, the raising of aperture opening ratio will reduce current density, reduce to drive pixel drive voltage; The raising of aperture opening ratio also will reduce the electric current that each sub-pixel consumes, so that the TFT size in the pixel-driving circuit can be done littlely, further improve the panel aperture opening ratio, form benign cycle.Above-mentioned advantage will be so that the panel power consumption significantly reduces, and the panel performance significantly promotes, and the life-span significantly prolongs.

Can be found out by above analysis, in the situation that production process and require that constant (cost of manufacture is constant, the live width that comprises simultaneously data line Vdata, sweep trace Vscan and power lead Vdd is constant), existing image element circuit domain is made amendment, with the short side direction of data line Vdata and power lead Vdd design at the strip sub-pixel, with the long side direction of sweep trace Vscan design at the strip sub-pixel, shown in Fig. 2 g.Compare following three characteristics with existing layout design: 1, the address signal of switch transistor T 1 grid becomes long side direction by the sub-pixel short side direction, namely becomes vertical direction by horizontal direction; 2, the data-signal of switch transistor T 1 source electrode data and power lead VDD change short side direction into by the sub-pixel long side direction, namely become horizontal direction by vertical direction; 3, the luminous organic material evaporation area vertical direction height of sub-pixel is constant, but the increase of horizontal direction width takes the space after power lead Vdd removes, shown in Fig. 2 a～2g.

Adopt the image element circuit domain of the present embodiment, the driving method of AMOLED panel substitutes existing line scanning addressing mode by the column scan addressing mode, namely uses from left to right (or from right to left) display mode that is listed as to substitute the from top to bottom display mode of (or from top to bottom) delegation of delegation.

Adopt the mode that driving circuit is combined with the image element circuit domain in above-described embodiment, its advantage is, the column-row arrangement mode that changes in the above-mentioned image element circuit layout design just in time is conducive to the formation of above-mentioned driving circuit.

Those of ordinary skill in the art will appreciate that, embodiment described here is in order to help reader understanding's principle of the present invention, should to be understood to that protection scope of the present invention is not limited to such special statement and embodiment.Those of ordinary skill in the art can make various other various concrete distortion and combinations that do not break away from essence of the present invention according to these technology enlightenments disclosed by the invention, and these distortion and combination are still in protection scope of the present invention.

Claims (2)

1. AMOLED panel drive circuit, comprise driver element and sub-pixel unit, driver element comprises scanning pin and data pin, sub-pixel unit comprises rows and sub-pixel column, rows comprises the identical sub-pixel of glow color that belongs to all pixels of delegation, and sub-pixel column comprises whole RGB sub-pixels of all pixels that belong to same row; It is characterized in that, the data-signal input end of all sub-pixels of described rows links together and is connected with the data pin of driver element, and the sweep signal input end of all sub-pixels of sub-pixel column links together and is connected with the scanning pin of driver element.

2. AMOLED panel driving method corresponding with above-mentioned driving circuit may further comprise the steps:

A, addressing the first rows: all R sub-pixels of the first row pixel are all chosen simultaneously, input simultaneously the data-signal of this rows;

B, addressing next son pixel column: this sub-pixel is all chosen simultaneously, inputs simultaneously the data-signal of this rows;

C, repeating step b return step a after the to the last data-signal of rows input is finished, and enter simultaneously the addressing of next frame cycle.

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