KR20070119200A - Organic light emitting diode - Google Patents

Abstract

An organic light emitting display device is provided to reduce an IR(InfraRed) drop by directly supplying driving signals to respective driving voltage supply lines without using a common line. An organic light emitting display device includes a driving voltage source, a ground voltage source, plural pixels(128), a data driving circuit(124), and plural driving voltage supply lines(C1-Cm). The plural pixels are formed in pixel regions, which are defined by plural data lines and plural gate lines. The pixel includes an LED which is driven by a current flowing between the driving voltage source and the ground voltage source. The data driving circuit supplies data to the data lines. The driving voltage supply lines are formed to be parallel to the data lines and supply the driving voltages to the pixels.

Description

Organic Light Emitting Diodes

1 is a diagram illustrating a light emitting principle of a conventional organic light emitting diode display device.

2 is a block diagram schematically illustrating a conventional organic light emitting diode display device.

3 and 4 are driving circuit diagrams for driving the pixel shown in FIG.

FIG. 5 is a plan view illustrating a portion “A” of FIG. 1. FIG.

FIG. 6 is a cross-sectional view of the portion “B” of FIG. 5. FIG.

FIG. 7 is a diagram for showing that an IR drop increases as the diverging point moves away from the supply pad 10.

8 is a block diagram illustrating an organic light emitting diode display device according to a first exemplary embodiment of the present invention.

FIG. 9 is a diagram illustrating a signal line arrangement in the data driving circuit of FIG. 8; FIG.

10 is a block diagram illustrating an organic light emitting diode display device according to a second exemplary embodiment of the present invention.

FIG. 11 is a diagram illustrating a signal line arrangement in the data driving circuit of FIG. 10. FIG.

12 is a block diagram illustrating an organic light emitting diode display device according to a third exemplary embodiment of the present invention.

13 is a block diagram illustrating an organic light emitting diode display device according to a fourth exemplary embodiment of the present invention.

<Description of the reference numerals for the main parts of the drawings>

120,220,320,420: OLED panel 122,222,322,422: Gate driving circuit

124,224,324,424: Data driving circuit 126,226,326,426: Gamma voltage generator

127,227,327,427: timing controller 128,228,328,428: pixel

Vd1 to Vdm: Data voltage supply pad Vdd: Drive voltage supply pad

C1 to Cm, C1 to Cm / 2, C1 to Cn, C1 to Cn / 2: drive voltage supply line

C11 to C (m / 2) 2, C11 to C (n / 2) 2: driving voltage branch line

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting diode display device. In particular, the driving voltage supply lines are formed parallel to the data lines via the data driving circuit, or the driving voltage supply lines are parallel to the gate lines via the gate driving circuit. The present invention relates to an organic light emitting diode display device which can improve the display quality by increasing the yield by reducing the IR drop.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include liquid crystal displays (hereinafter referred to as "LCDs"), field emission displays (FEDs), plasma display panels (hereinafter referred to as "PDPs") and electric fields. Light emitting devices; and the like.

Among them, PDP is attracting attention as the most favorable display device for light and small size and large screen because of its simple structure and manufacturing process, but it has the disadvantages of low luminous efficiency, low luminance and high power consumption. Active matrix LCDs with thin film transistors (hereinafter referred to as "TFTs") as switching devices are difficult to screen due to the use of semiconductor processes, but demand is increasing as they are mainly used as display devices in notebook computers. In contrast, the electroluminescent device is classified into an inorganic electroluminescent device and an organic light emitting diode device according to the material of the light emitting layer. The electroluminescent device is a self-light emitting device that emits light.

The organic light emitting diode device includes an anode electrode made of a transparent conductive material on a glass substrate as shown in FIG. 1, and includes an organic compound layer sequentially stacked thereon and a cathode electrode made of a conductive metal.

The organic compound layer includes a hole injection layer, a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and an electron injection layer. do.

When a driving voltage is applied to the anode electrode and the cathode electrode, holes in the hole injection layer and electrons in the electron injection layer proceed toward the light emitting layer to excite the light emitting layer, thereby causing the light emitting layer to emit visible light. Thus, an image or an image is displayed by the visible light generated from the light emitting layer.

Such an organic light emitting diode device has been applied as a passive matrix display device or an active matrix display device using a TFT as a switching device. In the passive matrix method, the anode and cathode electrodes are orthogonal to select the light emitting cells according to the currents applied to the electrodes, whereas the active matrix method selectively turns on the active TFTs to select and store the light emitting cells. The light emission of the light emitting cell is maintained at a voltage maintained in a capacitor.

FIG. 2 is a block diagram schematically illustrating a conventional organic light emitting diode display device. Referring to FIG. 2, a conventional organic light emitting diode display device may be arranged in regions defined by intersections of a gate line GL and a data line DL. The OLED panel 20 including the pixels 28, the gate driving circuit 22 driving the gate lines GL1 to GLn of the OLED panel 20, and the data lines of the OLED panel 20 ( A data driver circuit 24 for driving DL1 to DLm, a gamma voltage generator 26 for supplying a plurality of gamma voltages to the data driver circuit 24, the data driver circuit 24, and the gate driver circuit 22; It includes a timing control unit 27 for controlling.

In the OLED panel 20, pixels 28 are arranged in a matrix. The OLED panel 20 is provided with a supply pad 10 that receives a high potential voltage from an external high potential voltage source VDD and a base pad 12 that receives a base voltage from an external base voltage source GND. do. The high potential voltage supplied to the supply pad 10 is supplied to the respective pixels 28 through a plurality of driving voltage supply lines C1 to Cm branched from the common line COML. Here, the common line COML is formed orthogonal to the data lines DL1 to DLm between the data driving circuit 24 and the OLED panel 20. Meanwhile, the base voltage supplied to the base pad 12 is also supplied to each pixel 28.

The gate driving circuit 22 sequentially drives the gate lines GL1 through GLn by supplying a gate signal to the gate lines GL1 through GLn.

The gamma voltage generator 26 supplies a gamma voltage having various voltage values to the data driving circuit 24.

The data driving circuit 24 converts the digital data signal input from the timing controller 27 into an analog data signal using the gamma voltage from the gamma voltage generator 26. The data driving circuit 24 supplies an analog data signal to the data lines DL whenever the gate signal is supplied.

The timing controller 27 generates a data control signal for controlling the data driving circuit 24 and a gate control signal for controlling the gate driving circuit 22 using a plurality of synchronization signals. The data control signal generated by the timing controller 27 is supplied to the data driving circuit 24 to control the data driving circuit 24. The gate control signal generated by the timing controller 27 is supplied to the gate driving circuit 22 to control the gate driving circuit 22. In addition, the timing controller 27 supplies the digital data signal supplied from the scaler to the data driving circuit 24.

Each of the pixels 28 receives a data signal from the data line DL when the gate signal is supplied to the gate line GL, and generates light corresponding to the data signal.

To this end, each of the pixels 28 includes an OLED element 0LED having a cathode connected to a base voltage source GND (voltage supplied from the base pad 12) and a gate line as shown in FIGS. 3 and 4. (GL), a data line (DL) and a high potential voltage source (VDD) (voltage supplied from the supply pad 10) and connected to the anode of the OLED element for driving the OLED element (0LED) Cell drive circuits 30a and 30b are provided.

However, the general voltage driven cell driving circuit 30a shown in FIG. 3 includes two transistors T1 and T2 and one capacitor C1, and is mainly used for current compensation for uniformity and reliability compensation. The cell driving circuit 30b includes four transistors S1, S2, M1, M2 and one capacitor Cst as shown in FIG. Therefore, when each of the pixels 28 is driven by the current driving cell driving circuit 30b, the driving voltage supply line C, the base voltage supply line (not shown), the data line DL, the first and the At least five signal lines such as the second gate lines GL1 and GL2 are connected to each of the pixels 28.

As such a large number of signal lines are complicatedly input, crossover between signal lines occurs in an external region of the OLED panel 20 which is a pixel region, for example, an area of “A” portion of FIG. 1. . 5 is an enlarged view of portion “A” of FIG. 1, and FIG. 6 is a cross-sectional view of portion “B” of FIG. 5. 5 and 6, a conventional organic light emitting diode display device includes a plurality of data lines in a direction crossing the data lines DLj to DLj + 3 between the data driving circuit 24 and the OLED panel 20. Common lines (COML) formed on the DLj to DLj + 3) is provided. Since the cross-over common line (COML) is generally wide, when conductive particles are generated during the deposition process through the CVD process, data short and overlapping data lines formed in the lower part are overlapped to cause a panel defect. There is a problem that causes.

In addition, in the case of arranging the common line COML between the data driving circuit 24 and the OLED panel 20 in the conventional organic light emitting diode display device, the voltage at the point where the driving voltage supply lines C1 to Cm are branched is a branch point. There is a problem that decreases away from the supply pad (10). That is, as shown in FIG. 7, the branch voltages V1 to Vm of the driving voltage supply lines C1 to Cm branched from the common line COML increase as the branch points move away from the supply pad 10. It is reduced by the drop component. This is because the line resistance increases as the branch point moves away from the supply pad 10, and the driving voltage decreases in proportion to the increased line resistance value. For this reason, in the case where the common line COML is disposed between the data driving circuit 24 and the OLED panel 20 in the conventional organic light emitting diode display device, the driving of the branching point becomes farther away from the supply pad 10 in the horizontal direction. The voltage VDD is sharply reduced, so that the brightness is sharply lowered.

Accordingly, an object of the present invention is to improve the yield by forming the driving voltage supply lines in parallel to the data lines via the data driving circuit, or by forming the driving voltage supply lines in parallel to the gate lines via the gate driving circuit. At the same time, to provide an organic light emitting diode display device that can improve the display quality by reducing the drop of the eye.

In order to achieve the above object, the organic light emitting diode display device according to an embodiment of the present invention includes a driving voltage source for generating a driving voltage; A base voltage source generating a base voltage; an organic light emitting diode device formed in pixel areas defined by a plurality of data lines and a plurality of gate lines and emitting light by a current flowing between the driving voltage source and the base voltage source, respectively; A plurality of pixels comprising; A data driver circuit for supplying data to the data lines; And a plurality of driving voltage supply lines formed in parallel with the data lines via the data driving circuit to supply the driving voltage to each of the pixels.

The driving voltage supply line and the data line are alternately arranged.

On the other hand, at least two or more data lines may be disposed between two adjacent driving voltage supply lines.

In another embodiment, an organic light emitting diode display device includes: a driving voltage source generating a driving voltage; A base voltage source for generating a base voltage; A plurality of pixels each including an organic light emitting diode element formed in pixel areas defined by a plurality of data lines and a plurality of gate lines and emitted by a current flowing between the driving voltage source and the base voltage source; A data driver circuit for supplying data to the data lines; A gate driving circuit for supplying scan signals to the gate lines; And a plurality of driving voltage supply lines formed in parallel with the gate lines via the gate driving circuit to supply the driving voltage to each of the pixels.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 8 to 13.

8 is a block diagram illustrating an organic light emitting diode display device according to a first exemplary embodiment of the present invention, and FIG. 9 is a diagram illustrating a signal line arrangement in the data driving circuit of FIG. 8.

First, referring to FIG. 8, the organic light emitting diode display according to the first exemplary embodiment of the present invention includes pixels 128 arranged in regions defined by intersections of the gate line GL and the data line DL. The OLED panel 120, the gate driving circuit 122 driving the gate lines GL1 to GLn of the OLED panel 120, and the data lines DL1 to DLm of the OLED panel 120. A timing controller for controlling the data driver circuit 124, the gamma voltage generator 126 for supplying a plurality of gamma voltages to the data driver circuit 124, and the data driver circuit 124 and the gate driver circuit 122. 127).

In the OLED panel 120, the pixels 128 are arranged in a matrix form.

The gate driving circuit 122 supplies gate signals to the gate lines GL1 to GLn to sequentially drive the gate lines GL1 to GLn.

The gamma voltage generator 126 supplies a gamma voltage having various voltage values to the data driver circuit 124.

The data driving circuit 124 converts the digital data signal input from the timing controller 127 into an analog data signal using the gamma voltage from the gamma voltage generator 126. The data driving circuit 124 supplies an analog data signal to the data lines DL1 to DLm every time a gate signal is supplied. In addition, the data driving circuit 124 serves as a path through which a driving voltage generated from an external high potential voltage source VDD is supplied to each of the pixels 128. To this end, the data driving circuit 124 is designed such that a driving voltage can be output to each of the pixels 128 through itself when manufactured. In this case, the supply pads Vd1 to Vdm formed in the data driving circuit 124 to supply the data voltage and the supply pads Vdd for supplying the driving voltage may be alternately arranged as shown in FIG. 9. . The data voltage supply pads Vd1 to Vdm are respectively connected to the data lines DL1 to DLm, and the driving voltage supply pads Vdd are respectively connected to the driving voltage supply lines C1 to Cm. As a result, the organic light emitting diode display according to the first exemplary embodiment of the present invention allows the driving signal and the data signal to be input to the OLED panel 120 in a one-to-one correspondence through the data driving circuit 124, thereby providing the data lines DL1 to D. The common line COML formed on the data lines DL1 to DLm in a direction crossing the DLm may be omitted. As a result, the organic light emitting diode display according to the first exemplary embodiment of the present invention can prevent the electrical short between the common line COML and the data line DL from occurring, and does not pass through the common line COML. The IR drop may be reduced by directly supplying a driving signal from the data driving circuit 124 to the driving voltage supply lines C1 to Cm.

The timing controller 127 generates a data control signal for controlling the data driving circuit 124 and a gate control signal for controlling the gate driving circuit 122 using a plurality of synchronization signals. The data control signal generated by the timing controller 127 is supplied to the data driving circuit 124 to control the data driving circuit 124. The gate control signal generated by the timing controller 127 is supplied to the gate driving circuit 122 to control the gate driving circuit 122. In addition, the timing controller 127 supplies the digital data signal supplied from the scaler to the data driving circuit 124.

Each of the pixels 128 receives a data signal from the data lines DL1 to DLm when the gate signal is supplied to the gate lines GL1 to GLn, and generates light corresponding to the data signal.

FIG. 10 is a block diagram illustrating an organic light emitting diode display device according to a second exemplary embodiment of the present invention, and FIG. 11 is a diagram illustrating a signal line arrangement in the data driving circuit of FIG. 10.

First, referring to FIG. 10, an organic light emitting diode display according to a second exemplary embodiment of the present invention includes pixels 228 arranged in regions defined by intersections of a gate line GL and a data line DL. The OLED panel 220, the gate driving circuit 222 driving the gate lines GL1 to GLn of the OLED panel 220, and the data lines DL1 to DLm of the OLED panel 220. A timing controller for controlling the data driver circuit 224, the gamma voltage generator 226 that supplies a plurality of gamma voltages to the data driver circuit 224, and the data driver circuit 224 and the gate driver circuit 222. 227).

In the OLED panel 220, pixels 228 are disposed in a matrix form.

The gate driving circuit 222 sequentially drives the gate lines GL1 through GLn by supplying a gate signal to the gate lines GL1 through GLn.

The gamma voltage generator 226 supplies a gamma voltage having various voltage values to the data driver circuit 224.

The data driving circuit 224 converts the digital data signal input from the timing controller 227 into an analog data signal using the gamma voltage from the gamma voltage generator 226. The data driving circuit 224 supplies an analog data signal to the data lines DL1 to DLm every time a gate signal is supplied. In addition, the data driving circuit 224 serves as a path through which a driving voltage generated from an external high potential voltage source VDD is supplied to each of the pixels 228. To this end, the data driving circuit 224 is designed such that a driving voltage can be output to each of the pixels 228 through itself when manufactured. At this time, the supply pads Vd1 to Vdm for supplying the data voltage and the supply pads Vdd for supplying the driving voltage are formed in the data driving circuit 224 at a ratio of 2: 1 as shown in FIG. 11. Can be arranged. The data voltage supply pads Vd1 to Vdm are respectively connected to the data lines DL1 to DLm, and the driving voltage supply pads Vdd are respectively connected to the driving voltage supply lines C1 to Cm / 2. The driving voltage supply lines C1 to Cm / 2 are branched into the driving voltage branching lines C11 to C (m / 2) 2 so as to correspond to the data lines DL1 to DLm one-to-one. As a result, the organic light emitting diode display device according to the second embodiment of the present invention can reduce the number of driving voltage supply lines C1 to Cm / 2 by half compared to the first embodiment, and thus the size of the data driving circuit 224. Can be reduced. Of course, in the organic light emitting diode display according to the second embodiment, the driving signal and the data signal correspond one-to-one through the data driving circuit 224 similarly to the organic light emitting diode display according to the first embodiment. In this case, the common line COML formed on the data lines DL1 to DLm in the direction crossing the data lines DL1 to DLm may be omitted. As a result, the organic light emitting diode display according to the second embodiment of the present invention can prevent the electrical short between the common line COML and the data line DL from occurring, and does not pass through the common line COML. The IR drop may be reduced by directly supplying a driving signal from the data driving circuit 224 to each of the driving voltage supply lines C1 to Cm / 2.

The timing controller 227 generates a data control signal for controlling the data driving circuit 224 and a gate control signal for controlling the gate driving circuit 222 using a plurality of synchronization signals. The data control signal generated by the timing controller 227 is supplied to the data driving circuit 224 to control the data driving circuit 224. The gate control signal generated by the timing controller 227 is supplied to the gate driving circuit 222 to control the gate driving circuit 222. In addition, the timing controller 227 supplies the digital data signal supplied from the scaler to the data driving circuit 224.

Each of the pixels 228 receives data signals from the data lines DL1 to DLm when the gate signals are supplied to the gate lines GL1 to GLn to generate light corresponding to the data signals.

12 is a block diagram illustrating an organic light emitting diode display device according to a third exemplary embodiment of the present invention, and FIG. 13 is a block diagram illustrating an organic light emitting diode display element according to a fourth exemplary embodiment of the present invention.

FIG. 12 illustrates an organic light emitting diode display device which supplies a driving voltage via a gate driving circuit, unlike the first and second embodiments in which the driving voltage is supplied via a data driving circuit, and FIG. 13 shows a gate driving circuit. In order to reduce the size of the furnace, an organic light emitting diode display device in which the number of driving voltage supply lines is reduced by half compared to FIG. 12 is illustrated. Since the third embodiment of the present invention shown in FIG. 12 has the same effect as the first embodiment described with reference to FIGS. 8 and 9, only the drawing symbols are given differently and detailed description thereof will be omitted. In addition, since the fourth embodiment of the present invention shown in FIG. 13 has the same effect as the second embodiment described with reference to FIGS. 10 and 11, only the reference numerals are given differently, and detailed description thereof will be omitted. .

Meanwhile, in the first to fourth embodiments according to the present invention, the driving voltage is limited to the high potential driving voltage VDD. However, the driving voltage is not limited thereto and includes the base voltage VSS.

As described above, the organic light emitting diode display device according to the present invention is conventionally formed on the data lines in the direction crossing the data lines by allowing the driving signal and the data signal to be simultaneously input to the OLED panel through the data driving circuit. The line can be omitted. In addition, the organic light emitting diode display according to the present invention omits the conventional common line formed on the gate lines in the direction crossing the gate lines by simultaneously inputting the driving signal and the data signal to the OLED panel through the gate driving circuit. can do.

As a result, the organic light emitting diode display according to the present invention can prevent the electrical short between the common line and the data line from occurring. The organic light emitting diode display device can be driven directly from the data driving circuit to the respective driving voltage supply lines without passing through the common line. By supplying a signal, the IR drop can be reduced.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (6)

A driving voltage source for generating a driving voltage; A base voltage source for generating a base voltage; A plurality of pixels formed in pixel areas defined by a plurality of data lines and a plurality of gate lines, each pixel including an organic light emitting diode element emitting light by a current flowing between the driving voltage source and the base voltage source; A data driver circuit for supplying data to the data lines; And And a plurality of driving voltage supply lines formed through the data driving circuit and parallel to the data lines to supply the driving voltage to each of the pixels. The method of claim 1, And the driving voltage supply line and the data line are alternately arranged. The method of claim 1, And at least two data lines disposed between two adjacent driving voltage supply lines. A driving voltage source for generating a driving voltage; A base voltage source for generating a base voltage; A plurality of pixels formed in pixel areas defined by a plurality of data lines and a plurality of gate lines, each pixel including an organic light emitting diode element emitting light by a current flowing between the driving voltage source and the base voltage source; A data driver circuit for supplying data to the data lines; A gate driving circuit for supplying scan signals to the gate lines; And And a plurality of driving voltage supply lines which are formed in parallel with the gate lines via the gate driving circuit and supply the driving voltage to each of the pixels. The method of claim 4, wherein And the first driving voltage supply line and the gate line are alternately arranged. The method of claim 4, wherein At least two gate lines are disposed between two neighboring first driving voltage supply lines.

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