CN1632857A - LED display panel and D/A converter - Google Patents

LED display panel and D/A converter Download PDF

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Publication number
CN1632857A
CN1632857A CNA2005100046133A CN200510004613A CN1632857A CN 1632857 A CN1632857 A CN 1632857A CN A2005100046133 A CNA2005100046133 A CN A2005100046133A CN 200510004613 A CN200510004613 A CN 200510004613A CN 1632857 A CN1632857 A CN 1632857A
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film transistor
tft
thin film
area
play amount
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CN100367673C (en
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孙文堂
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AU Optronics Corp
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AU Optronics Corp
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Abstract

It is a light diode display panel, which comprises baseboard, picture element and A/D converter. The baseboard has the first area with thin film transistor of first channel mixed concentration and the second area with thin film transistor of second channel mixed concentration and with the picture element. The A/D converter comprises multiple switch circuits and current powers, wherein the circuits are optional conducted and located in the second area according to the gray degree. The powers are separately connected with the circuits and optionally output one current according to the conduction status of the circuits to generate the picture element current and are located in the first area.

Description

LED display panel and digital/analog converter thereof
Technical field
The present invention relates to a kind of LED display panel, and be particularly related to a kind of digital/analog converter.
Background technology
The luminosity of light-emitting diode pixel is directly proportional with the pixel current of being flowed through, so how it drives with current system.Provide corresponding pixel current by driving circuit according to different GTG values, make light-emitting diode pixel produce corresponding brightness according to pixel current.So the size of pixel current directly influences the luminosity of light-emitting diode pixel.And that the method that generally produces pixel current has is a variety of, how with thin film transistor (TFT) as current source, according to 2 NIndividual GTG value is set N current source and is produced N size of current respectively, is (2 in regular turn 0) I, (2 1) I, (2 2) I... (2 N-1) I etc., N is positive integer.When procedure for displaying, open corresponding current sources according to the GTG value, and the electric current that the current source of opening is exported is added General Logistics Department's output, think pixel current.
Please refer to Fig. 1, it illustrates is the circuit framework synoptic diagram of conventional digital/analog converter.Is the example explanation with digital/analog converter 100 in order to produce 8 kinds of pixel current IP, and it comprises 9 thin film transistor (TFT) QA1~QA3, QB1~QB3 and QC1~QC3.Thin film transistor (TFT) QA1~QA3 all is used for as current source, and the ratio of its channel width and length is respectively W/L, 2W/L and 4W/L, to produce electric current I, 2I, the 4I of different sizes respectively.
Suppose, when GTG value D is data-signal (D2 D2 D0)=(110) 2The time, not conducting of thin film transistor (TFT) QB1, electric current I via thin film transistor (TFT) QC1, QA1 to ground voltage, and thin film transistor (TFT) QB2, the QB3 factor number of it is believed that D2 and D1 are that noble potential is with conducting, so electric current 2I, 4I respectively via thin film transistor (TFT) QB2, QB3 and QA2, QA3 to ground voltage, and think pixel current IP.Therefore the pixel current IP that exported of digital/analog converter 100 will be 2I+4I=6I, and export corresponding pixel to, to show GTG value D=(110) 2The brightness of representative.
But digital/analog converter 100 is many at present to be realized with the low temperature polycrystalline silicon process technique, so that it is integrated in the display panel of light emitting diode indicator.Current source is to be realized by low-temperature polysilicon film transistor QA1~QA3, or is that the circuit that framework is formed is reached current source with other by thin film transistor (TFT).But framework come what may, utilize the produced thin film transistor (TFT) of low temperature polycrystalline silicon technology, its critical voltage (threshold voltage) all can cause variation because of the laser crystallization processing procedure with the side-play amount (Variation) of carrier transport factor, make each thin film transistor (TFT) as current source, QA1~QA3 for example, its each other critical voltage and the side-play amount of carrier transport factor will become different, cause the pixel current IP of digital/analog converter 100 outputs to have error to produce, and can't reach predetermined luminosity with the pairing electric current of GTG value D.
Please refer to Fig. 2, it is a conventional current source distribution synoptic diagram.Traditional solution is to allow the current source that produces electric current I, 2I, 4I, 8I spatially be evenly distributed, be that each current source all produces fixed current I ideally, for example produce 2I with two current sources to scale, produce 4I with four current sources, produce 8I etc. with 8 current sources, by that analogy.Please refer to Fig. 2, be evenly distributed on the space and be meant, when the pairing pixel current IP of GTG value D is 8I, produce 8I with eight current sources, its eight current sources are respectively A, B, C, D, E, F, G, the H among Fig. 2, and eight current source A, B, C, D, E, F, G, H are dispersed in the right and left, spatially be evenly distributed to reduce between each pixel current IP difference each other by this current source that will produce 8I.But this kind way can significantly increase the area of digital/analog converter 100.So for critical voltage and the carrier transport factor that solves because of thin film transistor (TFT) can cause variation because of the laser crystallization processing procedure, each thin film transistor (TFT) critical voltage each other that causes different with the side-play amount of carrier transport factor, making the uneven problem of picture, is that industry is badly in need of one of problem that solves.
Summary of the invention
In view of this, purpose of the present invention is providing a kind of LED display panel and digital/analog converter thereof exactly, and to solve the current source that each is realized with thin film transistor (TFT), its different problem of critical voltage side-play amount each other is to improve picture quality.
According to purpose of the present invention, a kind of digital/analog converter is proposed, it is to be used for LED display panel.LED display panel has substrate and at least one pixel.Substrate has first area and second area.Pixel comprises a first film transistor and a light emitting diode at least.The first film transistor in order to according to pixel current with the driven for emitting lights diode.The first film transistor is to be disposed at second area.Digital/analog converter comprises a plurality of on-off circuits and a plurality of current source.A plurality of on-off circuits are reached with at least one second thin film transistor (TFT) respectively and according to an optionally conducting of GTG value.A plurality of on-off circuits are to be disposed at second area.A plurality of current sources are reached with at least one the 3rd thin film transistor (TFT) respectively and are electrically connected with corresponding a plurality of on-off circuits respectively, and according to the conducting state of pairing a plurality of on-off circuits, optionally to export an electric current separately to produce pixel current.A plurality of current sources are to be disposed at the first area.
Wherein, the thin film transistor (TFT) that is formed at the first area is to have the first passage doping content, and the thin film transistor (TFT) that is formed at second area is to have the second channel doping content.Under the low temperature polycrystalline silicon processing procedure, the critical voltage of the thin film transistor (TFT) of first area (Threshold Voltage) side-play amount (variation) is first side-play amount, the critical voltage side-play amount of the thin film transistor (TFT) in the second area is second side-play amount, and first side-play amount is less than second side-play amount.
According to another object of the present invention, a kind of LED display panel is proposed, it comprises substrate, pixel and digital/analog converter.Substrate has first area and second area.Pixel comprises a first film transistor and a light emitting diode at least.The first film transistor is in order to according to pixel current driven for emitting lights diode and be disposed at second area.With the output pixel electric current, it comprises a plurality of on-off circuits and a plurality of current source to digital/analog converter according to the GTG value.A plurality of on-off circuits are reached with at least one second thin film transistor (TFT) respectively and according to the optionally conducting of GTG value.A plurality of on-off circuits are disposed at second area.A plurality of current sources are reached with at least one the 3rd thin film transistor (TFT) respectively.A plurality of current sources are to electrically connect with corresponding a plurality of on-off circuits respectively and according to the conducting state of pairing a plurality of on-off circuits, optionally to export an electric current separately to produce pixel current.A plurality of electric currents are to be disposed at the first area.
Wherein, the thin film transistor (TFT) that is formed at the first area is to have the first passage doping content, and the thin film transistor (TFT) that is formed at second area is to have the second channel doping content.Under the low temperature polycrystalline silicon processing procedure, the critical voltage of the thin film transistor (TFT) of first area (Threshold Voltage) side-play amount (variation) is first side-play amount, the critical voltage side-play amount of the thin film transistor (TFT) in the second area is second side-play amount, and first side-play amount is less than second side-play amount.
For above-mentioned purpose of the present invention, feature and advantage can be become apparent, a preferred embodiment cited below particularly, and conjunction with figs. are described in detail below.
Description of drawings
Fig. 1 is the circuit framework synoptic diagram of conventional digital/analog converter.
Fig. 2 is a conventional current source distribution synoptic diagram.
Fig. 3 is the dopant dose of low-temperature polysilicon film transistor and the experimental result picture of critical voltage.
Fig. 4 is the synoptic diagram according to a kind of electroluminescence body display panel of a preferred embodiment of the present invention.
Fig. 5 A is with the circuit diagram of thin film transistor (TFT) as an example of current source.
Fig. 5 B is with thin film transistor (TFT) another routine circuit diagram as current source.
Fig. 6 is for being the circuit framework synoptic diagram of an example with digital/analog converter 408 (1).
The reference numeral explanation
100: digital/analog converter
400: LED display panel
402: substrate
404: data drive circuit
406: pel array
408: digital/analog converter
410: scan drive circuit
Transistor: QA1, QA2, QA3, QB1, QB2, QB3, QC1, QC2, QC3, Q1, Q2, Q3
Embodiment
Low-temperature polysilicon film transistor is when processing procedure, and under different passage doping contents, the thin film transistor (TFT) that produces, its critical voltage have different side-play amount (Variation).Please refer to Fig. 3, its illustrate be low-temperature polysilicon film transistor with XeCl laser at energy 350mJ/cm 2Condition under the experimental result picture of resulting dopant dose and critical voltage.Transverse axis is represented the dopant dose (dopingdosage) of passage doping content, with cm -2Be unit.The longitudinal axis is represented critical voltage Vt, is unit with volt (voltage).Curve N is the dopant dose of NMOS and the relation curve of its critical voltage side-play amount, and curve P is the dopant dose of PMOS and the relation curve of its critical voltage side-play amount.Under different dopant doses, form different passage doping contents, make thin film transistor (TFT) have different critical voltage side-play amounts, error nodel line (error bar) E is in order to represent the size of critical voltage side-play amount (Variation).For example, be 1.0E+13cm at dopant dose -2The time, the size of the critical voltage side-play amount (Variation) of NMOS is the length that corresponds to error nodel line E.The long more expression side-play amount of error nodel line E is big more, that is the otherness of the critical voltage of expression NMOS is big more.Therefore as can be known, in the curve N, the critical voltage side-play amount maximum of NMOS is to be 1.0E+13cm at dopant dose -2The time.
Utilize this relation, find out the formed passage doping content under a certain dopant dose, the thin film transistor (TFT) that produces, its critical voltage side-play amount minimum, promptly the error nodel line is the shortest.For example PMOS is changed its passage doping content (channel doping) via doped with boron (Boron), and the critical voltage side-play amount (Variation) of finding out PMOS passage doping content hour, the point of the A among Fig. 3 for example, its dopant dose is 8.0E+12cm -2The time, the side-play amount of the critical voltage of PMOS (Variation) is to be minimum.So with this dopant dose 8.0E+12cm -2The thin film transistor (TFT) that made comes out, it is when using as current source, and the electric current that each current source is exported and the difference of ideal value make the digital-to-analog conversion pixel current that Lu exported more near ideal value minimum.
Please refer to Fig. 4, it illustrates is synoptic diagram according to a kind of electroluminescence body display panel of a preferred embodiment of the present invention.Electroluminescence body display panel comprises substrate 402, data drive circuit 404, scan drive circuit 410 and pel array 406.Substrate 402 for example is an electroluminescence body display base plate, and it is to have a first area L1 and a second area L2.Pel array 406 is made up of a plurality of pixel, each pixel comprises a thin film transistor (TFT) Q1 and an electroluminescence body at least, and the electroluminescence style is as being Organic Light Emitting Diode (Organic Light Emitting Diode) or macromolecule Organic Light Emitting Diode (Ploymer Light Emitting Diode) (thin film transistor (TFT) Q1 and electroluminescence body do not illustrate in Fig. 4).So electroluminescence body display panel is LED display panel for example.Thin film transistor (TFT) Q1 be in order to according to pixel current with the driven for emitting lights diode.Thin film transistor (TFT) Q1 is configured in second area L2.Scan drive circuit 410 be in regular turn the output scanning signal to pel array 406 so that each pixel receives corresponding pixel current IP ' (1)~IP ' (X), X is positive integer, scan drive circuit 410 is to be configured in second area L2.
Data drive circuit 404 according to the GTG value with output pixel electric current I P ' (1)~IP ' (X) and comprise a plurality of digital/analog converters 408 (1)~408 (X).Each digital/analog converter 408 (1)~408 (X) includes a plurality of on-off circuits and a plurality of current source (a plurality of on-off circuits and a plurality of current source are not illustrated among Fig. 4).A plurality of on-off circuits are to reach with at least one thin film transistor (TFT) Q2 respectively.A plurality of on-off circuits are according to the optionally conducting of GTG value, and are disposed at second area L2.A plurality of current sources are respectively to be reached by a thin film transistor (TFT) Q3 at least and to electrically connect with corresponding on-off circuit respectively, with the conducting state according to pairing on-off circuit, optionally to export an electric current separately to produce pixel current IP.A plurality of current sources are to be disposed at first area L1.Wherein, be formed at the thin film transistor (TFT) of first area L1, thin film transistor (TFT) Q3 for example, be to have the first passage doping content, be formed at the thin film transistor (TFT) of second area L2, for example thin film transistor (TFT) Q1 and Q2, be to have the second channel doping content, under the low temperature polycrystalline silicon processing procedure, critical voltage (ThresholdVoltage) side-play amount (variation) of the thin film transistor (TFT) Q3 of first area L1 is one first side-play amount, and the thin film transistor (TFT) Q1 among the second area L2, the critical voltage side-play amount of Q2 is second side-play amount, and first side-play amount is less than second side-play amount.
Furthermore, the present embodiment place different with tradition is: the conventional practice aspect, whole driving circuit, for example data drive circuit or scan drive circuit, all be made on the same substrate 402 with same passage doping content with pel array, this passage doping content for example is the second channel doping content, under the second channel doping content, the absolute value of the critical voltage of PMOS and NMOS is close, in order to circuit design.But under this passage doping content, the critical voltage side-play amount of thin film transistor (TFT) is bigger, and for example dopant dose is 2.0E+12cm among Fig. 3 -2The time, the critical voltage of PMOS and NMOS is near symmetry (B in Fig. 3, C 2 points).So, this moment, the error nodel line E ' of PMOS was down big compared to other dopant doses, so this dopant dose (2.0E+12cm -2) the critical voltage side-play amount of PMOS is bigger down.And present embodiment is in each digital/analog converter 408, and a plurality of current sources are to have the thin film transistor (TFT) of first passage doping content, and for example thin film transistor (TFT) Q3 realizes.Spirit by present embodiment, find out this side-play amount that makes critical voltage dopant dose hour via experiment,, be arranged among the first area L1 in the substrate 402 as the first passage doping content with passage doping content that this dopant dose was produced to form thin film transistor (TFT) Q3 under this first passage doping content.So, can obtain the thin film transistor (TFT) Q3 of critical voltage side-play amount minimum, to reduce a plurality of current sources element difference to each other that realizes with thin film transistor (TFT) Q3, so that the size of current that a plurality of current source produces all can approach ideal value.
And it is a variety of to realize that with thin film transistor (TFT) the method for current source has, and please refer to Fig. 5 A and Fig. 5 B, and Fig. 5 A is with the circuit diagram of thin film transistor (TFT) as an example of current source, and Fig. 5 B is with thin film transistor (TFT) another routine circuit diagram as current source.Among Fig. 5 A and Fig. 5 B, the size of the electric current when thin film transistor (TFT) Q3 all sets thin film transistor (TFT) Q3 conducting with different W/L ratios is to reach output current (2 0) I, (2 1) I... (2 N-1) I.Perhaps, utilize the mode of current mirror to realize current source.No matter, all realize with thin film transistor (TFT) Q3 with first passage doping content so which kind of thin film transistor (TFT) to be formed the current source framework with.So, each grade size of current that a plurality of current source in each digital/analog converter 408 is exported, it is more even all will to become.
Please refer to Fig. 6, it illustrates is to be the circuit framework synoptic diagram of an example with digital/analog converter 408 (1).To be arranged at first area L1 as thin film transistor (TFT) Q3 (the 1)~Q3 (N) of current source.Because the critical voltage side-play amount is to be minimum, so the electric current (2 that each grade current source is exported 0) I, (2 1) I... (2 N-1) I difference to each other will significantly reduce, and a plurality of on-off circuits are realized with thin film transistor (TFT) Q2 (0)~Q2 (N-1) and Q2 (0 ')~Q2 (N-1 '), and be arranged at second area L2.So, the pixel current IP ' that the pixel current IP ' (1) that digital/analog converter 408 (1) produces and digital/analog converter 408 (X) produce (X), difference will be littler each other.When identical GTG value D that all digital/analog converters 408 (1)~408 (K) receive, (K) difference will be littler than tradition each other for pixel current IP ' (the 1)~IP ' of each digital/analog converter 408 (1)~408 (K) output, also more near the pairing size of current of GTG value D, make whole display frame demonstrate traditional more even of identical brightness ratio.
And for each digital/analog converter 408 included a plurality of on-off circuits and other circuit, other circuit are scan drive circuit 410, pel array 406 and data drive circuit 404 for example, for the critical voltage side-play amount of thin film transistor (TFT), can't produce too much influence to its running.So except a plurality of current sources, remaining circuit all is arranged among the second area L2 of substrate 402 in the data drive circuit 404.In the second area L2 that uses the second channel doping content, the absolute value of the critical voltage of PMOS and NMOS is close, in order to circuit design.In the time of perhaps will being incorporated into scan drive circuit 410 on the display panel, also it be arranged at the second area L2 of substrate 402.
Disclosed LED display panel of the above embodiment of the present invention and digital/analog converter thereof, by finding out critical voltage side-play amount passage doping content hour, the thin film transistor (TFT) that produces with this passage doping content, its critical voltage side-play amount minimum, and a plurality of current sources in the digital/analog converter are realized with this thin film transistor (TFT), make the size of current of each grade current source, all will be more near ideal value.
In sum; though the present invention discloses as above with a preferred embodiment; right its is not in order to limit the present invention; anyly have the knack of this skill person; without departing from the spirit and scope of the present invention; when can being used for a variety of modifications and variations, so protection scope of the present invention is as the criterion when looking the accompanying Claim person of defining.

Claims (14)

1. digital/analog converter, be used for a LED display panel, this LED display panel has a substrate and at least one pixel, this substrate is to have a first area and a second area, this pixel comprises a first film transistor and a light emitting diode at least, this the first film transistor be in order to according to a pixel current to drive this light emitting diode, this first film transistor is to be disposed at this second area, this digital/analog converter comprises:
A plurality of on-off circuits are to reach with at least one second thin film transistor (TFT) respectively, and described on-off circuit is that described on-off circuit is to be configured in this second area according to an optionally conducting of GTG value; And
A plurality of current sources, be to reach with at least one the 3rd thin film transistor (TFT) respectively, described current source is to electrically connect with corresponding described on-off circuit respectively, and the conducting state of the pairing described on-off circuit of foundation, optionally to export an electric current separately to produce this pixel current, described current source is to be configured in this first area;
Wherein, the thin film transistor (TFT) that is formed on this first area is to have a first passage doping content, the thin film transistor (TFT) that is formed on this second area is to have a second channel doping content, under the low temperature polycrystalline silicon processing procedure, the critical voltage side-play amount of the thin film transistor (TFT) of this first area is one first side-play amount, the critical voltage side-play amount of the thin film transistor (TFT) in this second area is one second side-play amount, and this first side-play amount is less than this second side-play amount.
2. digital/analog converter as claimed in claim 1 wherein, in this digital/analog converter, has only described current source to be configured in this first area.
3. LED display panel comprises:
One substrate has a first area and a second area;
One pixel comprises a first film transistor and a light emitting diode at least, and this first film transistor is in order to driving this light emitting diode according to a pixel current, and this first film transistor is to be configured in this second area; And
One digital/analog converter, to export this pixel current, this digital/analog converter comprises according to a GTG value for it:
A plurality of on-off circuits are to reach with at least one second thin film transistor (TFT) respectively, and described on-off circuit is that described on-off circuit is to be configured in this second area according to an optionally conducting of GTG value; And
A plurality of current sources, be to reach with at least one the 3rd thin film transistor (TFT) respectively, described current source is to electrically connect with corresponding described on-off circuit respectively, and the conducting state of the pairing described on-off circuit of foundation, optionally to export an electric current separately to produce this pixel current, described current source is to be configured in this first area;
Wherein, the thin film transistor (TFT) that is formed on this first area is to have a first passage doping content, the thin film transistor (TFT) that is formed at this second area is to have a second channel doping content, under the low temperature polycrystalline silicon processing procedure, the critical voltage side-play amount of the thin film transistor (TFT) of this first area is one first side-play amount, the critical voltage side-play amount of the thin film transistor (TFT) in this second area is one second side-play amount, and this first side-play amount is less than this second side-play amount.
4. display panel as claimed in claim 3 wherein, in this digital/analog converter, has only described current source to be arranged on this first area.
5. display panel as claimed in claim 3, wherein, this display panel more comprises scan driving circuit, so that this pixel receives this pixel current, this scan drive circuit is arranged on this second area to this scan drive circuit output one scan signal to this pixel.
6. LED display panel is to comprise:
One substrate has a first area and a second area, and the thin film transistor (TFT) that is formed at this first area has a first passage doping content, and the thin film transistor (TFT) that is formed at this second area has a second channel doping content;
One pixel comprises a first film transistor and an Organic Light Emitting Diode at least, and this first film transistor is in order to driving this Organic Light Emitting Diode according to a pixel current, and this first film transistor is this second area of configuration;
Scan driving circuit, be output one scan signal to this pixel so that this pixel receives this pixel current, this scan drive circuit is to be disposed at this second area; And
One data drive circuit, to export this pixel current, this data drive circuit comprises a digital/analog converter according to a GTG value, this digital/analog converter comprises:
A plurality of on-off circuits are to be arranged at this second area and to be reached by the thin film transistor (TFT) of this second area, and described on-off circuit is according to this optionally conducting of GTG value; And
A plurality of current sources, be arranged on this first area and reached by the thin film transistor (TFT) of this first area, described current source is to electrically connect with corresponding described on-off circuit respectively, and the conducting state of the pairing described on-off circuit of foundation, optionally export an electric current separately to produce this pixel current;
Wherein, the critical voltage side-play amount of the thin film transistor (TFT) of this first area is one first side-play amount, and the critical voltage side-play amount of the thin film transistor (TFT) in this second area is one second side-play amount, and this first side-play amount is less than this second side-play amount.
7. electroluminescence body display panel is to comprise:
One pixel comprises a first film transistor and an electroluminescence body, this first film transistor be in order to according to a pixel current to drive this electroluminescence body;
A plurality of on-off circuits are that each is reached with one second thin film transistor (TFT) with a second channel doping content at least, and described on-off circuit is according to an optionally conducting of GTG value; And
A plurality of current sources, be that each is reached with one the 3rd thin film transistor (TFT) with a first passage doping content at least, described current source is to electrically connect with corresponding described on-off circuit respectively, and the conducting state of the pairing described on-off circuit of foundation, optionally to export an electric current separately to produce this pixel current;
Wherein, this first passage doping content is different with this second channel doping content.
8. electroluminescence body display panel as claimed in claim 7, wherein, the critical voltage side-play amount that the critical voltage side-play amount that described the 3rd thin film transistor (TFT) is had is had less than described second thin film transistor (TFT).
9. electroluminescence body display panel as claimed in claim 7, wherein, the critical voltage side-play amount that this first passage doping content is described the 3rd thin film transistor (TFT) is hour pairing doping content.
10. electroluminescence body display panel as claimed in claim 7, wherein, this second thin film transistor (TFT) and the 3rd thin film transistor (TFT) are low-temperature polysilicon film transistors.
11. an electroluminescence body display base plate comprises:
A plurality of electroluminescence bodies;
A plurality of current sources are reached by a plurality of thin film transistor (TFT)s with a first passage doping content; And
A plurality of on-off circuits, reached by a plurality of thin film transistor (TFT)s with a second channel doping content, these a plurality of current sources are to electrically connect with a plurality of on-off circuits of corresponding this respectively, and according to the conducting state of pairing this a plurality of on-off circuits to drive these a plurality of electroluminescence bodies of correspondence;
Wherein, this first passage doping content is different with this second channel doping content.
12. electroluminescence body display base plate as claimed in claim 11, wherein, this first passage doping content is the critical voltage side-play amount hour pairing doping content of these a plurality of thin film transistor (TFT)s with this first passage doping content.
13. electroluminescence body display base plate as claimed in claim 11, wherein, the critical voltage side-play amount of these a plurality of thin film transistor (TFT)s with this first passage doping content is less than these a plurality of critical voltage side-play amounts with thin film transistor (TFT) of this second channel doping content.
14. electroluminescence body display base plate as claimed in claim 11, wherein, these a plurality of thin film transistor (TFT)s with this first passage doping content are low-temperature polysilicon film transistors with these a plurality of thin film transistor (TFT)s with this second channel doping content.
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CN107221291A (en) * 2017-07-31 2017-09-29 上海天马微电子有限公司 Display substrate, display panel, driving method of display panel and display device

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