TWI290311B - Active matrix organic light emitting diode pixel circuit with current auto compensated function - Google Patents

Abstract

An active matrix organic light emitting diode pixel circuit with current auto-compensated function is disclosed. An active load is disposed on the driving current transmitting path of the active matrix organic light emitting diode pixel. The driving current flow through the organic light emitting diode is auto-compensated when the voltage of the organic light emitting diode becomes larger in a period of time. Therefore, the intensity uniformity of display is improved.

Description

1290311 V. Description of invention (1)

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to one aspect, and more particularly to a light emitting diode pixel circuit. Active matrix organic light-emitting diode pixel type can automatically compensate current active matrix organic prior art With the development of information technology, various information devices such as computers, mobile phones, personal digital assistants (PDAs) and digital cameras They are constantly introducing new ideas. Among these information devices, displays have always played a pivotal role, and flat panel displays have become increasingly popular due to their thinness, light weight and power saving features. Among various flat panel displays, the Active Matrix Organic Emitting Diode (AM0LED) has advantages such as wide viewing angle, good color contrast effect, fast response speed and low performance. Suitable for applications such as electronic clocks, mobile phones, personal assistants and digital cameras. . However, in the active matrix organic light-emitting diode (AM〇LED) pixel circuit, it is known because of its organic light-emitting diode (3) ^ (8) component span. ‘ will gradually increase as the operating time increases, and it will also affect the voltage of the Thin Film Transistor (TFT). In general, the display brightness of the organic light-emitting diodes #, *, 〃IL, and the current I d of the organic light-emitting diode are proportional to each other, and the current Id flowing through the organic light-emitting diode is calculated as follows: ^ When the thin film transistor is N-type and Vds is smaller than Vgs-Vt, Id==kJ (W/L)[(Vgs-Vt)Vds-(l/2)(Vds)(Vds)]. (1)

Page 5 1290311 V. Description of invention (2) When the thin film transistor is N disk and Vds is greater than or equal to Vgs-Vt

Id = (l/2)kJ (W/L)(Vgs-Vt) (Vgs-Vt) ............(2) When the thin film transistor is P type and Vsd is smaller than Vsg- Vt

Id-k5 (W/L)[(Vsg-Vt)Vsd-(l/2)(Vsd)(Vsd)]..(3) When the thin film transistor is P type and Vsd is greater than or equal to Vsg-Vt

Id-(l/2)k, (W/L)(Vsg-Vt) (Vsg-Vt)............(4) Knowing that 'when Vgs (or Vsg) or Vds (or Vsd) When the organic light-emitting diode element is lowered across the voltage, the current I d flowing through the organic light-emitting diode is reduced, which affects the brightness of the display panel. In addition, due to the difference in the playing time and time of the user, the increase in the cross-pressure of the organic light-emitting element in each pixel will be different, thus causing the entire display brightness to drop. Uneven phenomenon. SUMMARY OF THE INVENTION The present invention provides an active moment riser that automatically compensates for current, which automatically compensates for current flowing through the organic light-emitting diode across the span of the organic light-emitting diode. , , , 'To achieve the above and other purposes, a >; active matrix organic light-emitting diode pixel from: active current matrix of compensation current _: = halogen circuit. The circuit module for automatically compensating for the LED body of the LED includes: the active matrix has a diode and has a bamboo light load. Among them, the active matrix organic light-emitting array organic light-emitting diode 2: the organic light-emitting diode for the body, and the current-transmitting current of the active polar body is 显^, which is the current flowing through the organic light-emitting diode Transmission path η: household: f疋: and the active load is equipped with two 1 will automatically compensate for the flow through the organic light ~

10765t.wf.ptd face

Page 6 1290311 V. Invention Description (3) The current of the polar body includes: ί: Ν 型 曰 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 主动 : : : : : : : : : : : : : : : : Pole, 汲Ξ-汲Ξ and Γ, Γ? The thin film transistor has a first-to-interstitial and a second-free source; the dyad:::-type thin-twisted transistor has a second organic light-emitting diode, 1^ ώ ^ For the younger end and the second end; w is: the first - the extreme. The _ system is extremely 禺 禺 第一 = = ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; - Connect to the second source, pass Ϊ:,: Configure the load to be placed between the anode terminal and the second source, or place the active load on the current transmission path between the positive terminal and the source. And /, brother / / pole In another embodiment, the basin active moment is right: ν-type thin film transistor, Ρ-type thin diode pixel package. Wherein, the n-type thin film body and va:, and the organic light emitting second brother:: the primary pole; the p-type thin film transistor has a second interpole, the first, the and; = a source; the capacitor and the Guchu Mountain η The younger one and the other are the anode end and the bungee pole 5 f and the second end of the brother; the organic light-emitting diode has the G and the extreme. The coupling relationship is: /, β J : the first-pole is coupled to the data line, the second gate is coupled to the first _ % ^ ^, and the second is coupled to the second gate, the first-end coupling The pile-source, the anode end is coupled to the second drain:: the coupling end. u k pole is coupled to the power supply negative

1290311 V. INSTRUCTIONS (4) Among them, the active load is placed on the anode flow path, or the active load is placed on the current transmission path between the two: In another embodiment of the power source positive terminal and the second source, the active matrix barrier includes: a first-N type thin film transistor, a: a polar body pixel package, a first-electrode; and a source film transistor has a first - Open organic, 4; Capacitor has a first end and a second end. With i:; Extreme and cathode ends. The coupling relationship is (7) the fault is connected to the trace line, the first drain pole is connected to the first source, the first core is connected to the beta line, and the second pole is coupled to the pole power supply. #第一端福The second brother is connected to the second source, and the cathode end is coupled to the second drain. And the handle arch to the positive end of the power supply and the flow transmission path: the second = 2: the current between the cathode and the second drain; the way: the load is placed at the negative end of the power supply and the second source On the - Ϊ 型 type on the thin film: the active load of the two can be connected to the gate and the pole. Type thin A: crystal 'can also be interpolar and " pole connected in - dynamic complement: i ϊ: = in: know 'should' with the active load that can be self-twisted by the two-way transmission path provided by the present invention, in organic Hair br, then with: 1⁄2 'the cross-pressure will also flow through the current of the organic light-emitting diode with the voltage across the body; therefore, the automatic compensation flow through the fifth, the invention description ( 5) Current of the organic light emitting diode. In order to make the above description of the present invention easier to understand, the following description of the preferred embodiments, the features, and the advantages of the present invention will be more clearly described as follows: Basin rabbit organic light-emitting diode pixel diagram, '. The active matrix light-emitting diode pixel used in one example includes: the first N-turn display, the active matrix organic thin film transistor 120, the capacitor 130 and the /f transistor 110, and the second N-type mode is the first N-type Thin film transistor 11 亟, 140. The coupling-drain connection data line, the first source, the fish pull: the f-connected scan line, the second N-type thin film transistor 12〇, the first end of the valley 130 and the second drain of the (2) Connect the power supply two: the pole U pole is connected to the negative end of the power supply. As described above, the organic light-emitting diode 丄 organic light-emitting diode 14 〇 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 浐 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈 颈Λ Λ Λ quot Λ 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 The second gate of the 薄膜-type thin film transistor 120 is Wed Λ _ _. It is assumed that the voltage across the organic light-emitting diode 1 40 is the voltage Vds, and the gate voltage Vgs of the thin film transistor 120 is different from the source.

Vgs ' V§ - Vs = Vg - (VSS + Voled)

1290311 V. Description of invention (6)

Vds = Vd - Vs ^ Vdd ^ rvss ^ v ) Since the threshold of the second N-type thin film transistor 12() is f ed) (1) and the formula (2), and 7 > Knowing the 'voltage value of the type of material line', when organic::,: brightness, to transfer the capital rise, obviously, Vgs and Vds are '^ = two spans: V-diode M0 current Id will also decline. k via organic light emission f Referring to Fig. 2, it is a circuit diagram of a first per-matrix organic light-emitting diode pixel according to the present invention.贝,彳之^The main picture of the first-N-type thin film transistor 1 1 0, the second N-type "film coin not 曰' spear, the first capacity 130 and the organic light-emitting diode 14〇 =1120, electricity The second carrier of the thin film transistor 120 is further in the current transmission path formed by the second 140 type 140; the active negative 形成 formed by the 薄膜-type thin film transistor of the light-emitting diode The pole is connected to the anode end of the diode uo and the second source is loaded with the organic light emitting element. Therefore, when the voltage across the organic light emitting diode 140 flows through the organic light emitting diode 14〇, , ^ r, ^ T „ #Vgs , Vds τ /Λ; 10 i 1: and can automatically compensate the electric Id flowing through the organic light-emitting diode 140. As shown in Fig. 4, where: the two-position load 2 1〇Vs voltage rise curve and 1 (1 line below the dotted line is the j current drop curve on the Vs voltage after the active load 21〇. Obviously, the flow through the rise curve and the (4) flow Id can be compensated The situation is lowered, and the automatic compensation is achieved = first result - the polar body is shown in Fig. 5, which is another 10765 twf according to the first embodiment of the present invention, ptd page 10! 311 V. INSTRUCTIONS (7) ~ Active matrix organic light-emitting two = Yes, this pixel circuit is two; 2::, N-type film connected with the active load 51 formed by different transistors in Figure 2 The % & „ of the N-type thin film transistor 120 is placed at the positive end of the power supply Vdd and the second method can be used to reduce the current of the organic light-emitting diode U〇 on the current transmission path by (4) s. To achieve automatic compensation flow, please refer to Figure 6, i1 salt. Organic light-emitting diode pixel display, the picture shows the active matrix light-emitting diode pixel used in the 22nd embodiment including the .W figure "not" The active matrix organic body 620, the capacitor 63 0 and the organic thin film transistor 610, and the P-type thin film electro-crystalline thin film transistor 6 · 0 of the first pole / 640 ° of the way to receive the N-type material line, the first, the original support, A 1 wood connection known line, the first pole connection 6 20 second door ^ shell 1, f 〒 63 0 first end and P type thin film transistor 63 0 first - second P, P type thin film The second source of the crystal 6 2 0 is connected to the capacitor body 64 ^ ^ ^ power supply positive shirt, the second drain is connected to the organic light emitting diode negative terminal Vss, The cathode end of the 64 〇 diode of the organic light-emitting diode is connected to the ground 1/^, and when the voltage across the organic light-emitting diode 64 is increased, the light-彳/ϋ is calculated by the formula (3). It can be seen that the current Id flowing through the organic hair:: pole body 640 will also decrease, so the automatic compensation circuit as shown in Fig. 7 and Fig. 8 is needed. Right Lt ΐ Fig. 7 'It is based on this The second embodiment of the active rectangular thin two-body pixel of the second embodiment of the present invention shows that, except for the sixth figure, the second day of the body 610, the P-type thin film transistor 62 〇, the capacitor 63 〇 and the organic hair -640, more in Figure 6, by p-type thin film transistor 62 〇 10765twf, pt.d 1290311 "― 丨 "_ 丨. V, invention description (8) two, the first and the extreme Organic light-emitting diode ^ ^ ^ ^ ^ ^ ^ The pole and the bungee are connected to the bottom of the thin body to form the active load 71〇, the classmates ^> 包日日体所. The battle 0 is disposed at the positive end of the power supply Vdd and the second source. Therefore, when the voltage across the organic light-emitting diode 640 rises, the flow rises through the organic light-emitting diode 5 〇iea, and the voltage across the guide also decreases. == When the stream Id drops 'active load 7Π ^ ^ . ί :: 7- FIV; "# ^,J ^ ^ ^ Please refer to Figure 8, V1; - ipH640 current Id. An active matrix organic luminescence II/Chu is that this pixel circuit will be a road map. Different from the brother 7 diagram, the active negative formed by the transistor: i 〇, the p-type film with the poles connected together The plug between the second poles of the crystal 620: f anode end and ? The type of thin film can be reduced by compensating for the Vsd:;,: the dynamic method also illuminates the effect of the current Id of the diode 640. 】Automatic complement "k through the organic eye, see Figure 9, 1 rabbit-organic light-emitting diode pixel diagram 'di two,: the active matrix light-emitting diode pixels used in the example include: tamping?: 'This active matrix The organic thin film transistor 920, the capacitor 93n month female / #胲 transistor 910, the second N-type mode is the first N-type thin film electro-crystal in the machine f-light diode 94〇. It is coupled to a drain connection data line, ^日—之第—The gate is connected to the scanning line, the second N-type thin film is electrically connected to the second pole=接!容... The second pole of the 920 is connected with a brother and a gate, and the second two N-type thin film transistor is connected to the capacitor 93 The cathode end of the second 浐 〇 94 94 94 94 94 94 94 94 94 94 94 94 94 94 94 94 94 94 94 94 Then, it is connected to the positive terminal Vdd of the power supply. When the voltage across the voltage of the organic light-emitting diode 940 rises, the vds will be IV, and the equation of (1) will be known to cause the flow through the organic light-emitting diode 9 The private stream I d of 40 will also decrease, so the automatic compensation circuit as shown in the figure and the figure is required. 0 is a circuit diagram of an active matrix organic light emitting diode according to a third embodiment of the present invention. The figure shows that, in addition to the 9th 匕 first-N type thin film transistor 91 〇, the second N type thin film The crystal 92 〇, the electric junction and the organic light emitting diode 940 are further formed by the second light source and the second source of the organic light emitting diode 940 and the second N type thin film transistor 92. In the current transmission path, the active load 1 pole formed by the skin transistor connected to the gate and the drain is connected between the anode and the negative terminal of the power supply. When the voltage across the 940 voltage rises and the current Id flowing through the organic light-emitting diode 94 decreases, the voltage across the active negative voltage 1010 also decreases, so that compensation is obtained, so that VT 63 ^ rises and Vds decreases. The amplitude also flows Id. The power of the automatic detection through the organic light-emitting diode 940 is shown in Figure 11, which is a circuit diagram of the active matrix organic light-emitting diode according to the present invention: 10 = Is 'this pixel circuit system will be the pole: - brother 10 picture of the different transistors formed by the initiative The N-type film of the load and the pole are connected together - the cathode end and the second flow path are carried out. This method can be used; the amplitude of the electric charge between the second and the second poles is reduced by the V ds of the supplement, 10765 twf. Ptd Page 13 1290311 V. Inventive Note (ίο) to achieve automatic compensation through the organic hair. Of course, if you are familiar with this art, the load should be the active load in the N-type thin film transistor embodiment, or in the thin film The crystal source is extreme, but the load, its actual configuration, as described above, at least 1. The invention can automatically compensate for the flow through the organic 2. The display can be improved. Although the present invention has been described in terms of preferred embodiments, Any of the above-mentioned embodiments may be P-type active in any of the above-mentioned embodiments, and the current I d of the patent application vane diode 94 can be used in various ways. Thin film transistor. It is placed at the extreme end of the thin-film transistor, or it can be configured with the needs of both active users at the same time. It has the following advantages: The current of the light-emitting diode. Degree and extend product life. The present invention is disclosed above, and it is not intended to be used by those skilled in the art without departing from the spirit and scope of the invention. _

10765t.wf.ptd Page 14 1290311 Brief Description of the Drawings Fig. 1 is a schematic diagram showing an active matrix organic light emitting diode used in the first embodiment; Fig. 2 is an active matrix organic according to a first embodiment of the present invention. LED pixel circuit diagram; FIG. 3 is a comparison diagram of voltage rise curves of an active matrix organic light emitting diode circuit according to a first embodiment of the present invention; FIG. 4 is a diagram showing an active matrix according to a first embodiment of the present invention. Comparison diagram of current decreasing curve of organic light emitting diode pixel circuit; Fig. 5 is a circuit diagram of another active matrix organic light emitting diode according to the first embodiment of the present invention; Fig. 6 is a diagram showing active use of the second embodiment Schematic diagram of a matrix organic light emitting diode pixel; FIG. 7 is a circuit diagram of an active matrix organic light emitting diode according to a second embodiment of the present invention; and FIG. 8 is a diagram showing another active matrix organic according to a second embodiment of the present invention. Light-emitting diode pixel circuit diagram; Figure 9 shows the active matrix organic light-emitting diode pixel used in the third embodiment FIG. 10 is a circuit diagram of an active matrix organic light emitting diode according to a third embodiment of the present invention; and FIG. 11 is a diagram showing another active matrix organic light emitting diode according to a third embodiment of the present invention. Circuit diagram. Schematic indication: 1 1 0, 9 1 0 first N-type thin film transistor

10765t.wf.ptd Page 15 1290311 Schematic description 120 130 140 210 Active load 92 0 Second N-type thin film transistor 630, 930 Capacitance 640, 940 Organic light-emitting diodes 510, 710, 810, 1010, 1110 6 1 0 N-type thin film transistor 6 2 0 P-type thin film transistor

10765t.wf.ptd Page 16

Claims (1)

1290311 VI. Application for Patent Range U An automatic compensation circuit for electrical circuits, including ··· Active matrix of organic light-emitting diodes like an active matrix organically produced organic light-emitting diode, the main body-by-body pixel with illumination The display brightness is determined by the size of the pixel current flowing through the organic light-emitting diode, and the active load of the first-polar diode-current transmission path is arranged in 兮+ and hexa-e. The current of the polar body "special transmission path to automatically compensate the flow 2 · The main photodiode pixel which can automatically compensate the current as described in the Shenqing patented moving matrix organic light emitting diode ^ includes: 〃 circuit, which makes the initiative The matrix organically emits a first germanium type thin film transistor, and has a first pole and a first source, one having a first gate, a first connected to a data line, and the first gate being lightly connected to the scan line, the first and the second pole The light-second ν-type thin film transistor has a: i: first: source, the second gate _ hai: v pole second second pole connected to a power positive terminal; The first dynasty and the second end are coupled to the first end and the second end, the second end is coupled to the second source; the <@ is coupled to the The organic light-emitting diode has an anode terminal and - the % is extremely coupled to the second source, the cathode terminal is coupled to a power source, and is automatically compensated as described in claim 2 An electric, illuminating diode pixel circuit, wherein the active negative system: the current transmission path between the edge IW terminal and the second source. 10765twf.ptd Page 17 1290311 Patent Application No. 4 · The active moment of the automatically compensated current according to item 2 of the patent application scope 2 has a light-emitting diode pixel circuit, wherein the active load is configured to be the positive end of the power supply The current transfer path between the second drain. 5. The main matrix organic light emitting diode pixel circuit capable of automatically compensating current according to the first aspect of the patent, wherein the active matrix organic light emitting diode pixel comprises: a N, a type of germanium film transistor, Having a first gate, a first drain, and a source, the first gate is coupled to the scan line, and the first drain is coupled to the anode of the P-type and the second gate. The moving matrix is at the positive source, the source positive terminal capacitance, the pole, the end of the connection is as applied to the extreme and 7 · as applied for the dynamic matrix organically issued at the positive end of the power supply 8 · as applied for the dynamic matrix organic hair the second , having a second terminal illuminating the second patent model - only two of the second patents - 亟 亟 and the patented phantom diode, having a second gate, a second pole and a gate coupling The first source has a first end and a second end, the first end is coupled to the second source; and the body has an anode end and a cathode end: =, the cathode end is connected to a power supply 'negative terminal'. The automatic compensation body pixel circuit described in the fifth item of the cofferdam, wherein the current transmission path between the active and the main poles of the active " The active load is matched with the current transmission path between the primary poles. The six-body pixel circuit can be automatically compensated according to the first item, wherein the active/;IL main & array organic 1290311 The photodiode pixel includes: a first N-type thin film transistor and a first source, the first gate is connected to the data line; and has a first gate and a first drain coupled to the scan line, the first The first light source and the first pole are coupled to the first source, the first source and the first source a negative terminal; taking the anode of the second gate 9. The moving matrix is in the negative 10 moving matrix in the electrical 11 moving matrix and > and the pole 12 moving matrix and the drain-capacitor, having a first end and a first end, the The second end is coupled to the second end; the second end is coupled to the second source; and the organic light emitting diode has an anode end and a cathode end, and the end is connected to a positive end of the power source, and the cathode end is coupled The second bungee. The main pole pixel circuit capable of automatically compensating current according to item 8 of the benefit range, wherein the active load is coupled to the current transmission path between the first pole and the second drain. For example, the patented range of organic light-emitting diode pixel circuits, "the end of the: and the second source of the two-loaded system" organic light-emitting diode pixel, the n-type film in which the employee current is connected \Crystal. The load is only for the gate. For example, the scope of the patent application is w = photodiode pixel electricity: ... the current: P-type thin and transistor connected together.