KR101958449B1 - Organic light emitting diode display device and method for driving the same - Google Patents

Abstract

The present invention relates to an organic light emitting diode display and a driving method thereof. An organic light emitting diode display according to an embodiment of the present invention includes a display panel divided into N blocks (N is a natural number of 2 or more) blocks; And a power supply circuit for supplying a high potential voltage to each of the N blocks, wherein the power supply circuit supplies a k th high potential voltage to a block k (k is a natural number satisfying 1? K? N) .

Description

Technical Field [0001] The present invention relates to an organic light emitting diode (OLED) display device,

The present invention relates to an organic light emitting diode display and a driving method thereof.

As the information society develops, the demand for display devices for displaying images is increasing in various forms. In recent years, various flat panel display devices such as a liquid crystal display (LCD), a plasma display panel (PDP), and an organic light emitting diode (OLED) have been used . Among these flat panel display devices, organic light emitting diode display devices are capable of low voltage driving, are thin, have excellent viewing angles, and have a high response speed. An active matrix type organic light emitting diode display device in which a plurality of pixels are arranged in a matrix form to display an image is widely used in organic light emitting diode display devices.

An active matrix type organic light emitting diode display device includes a plurality of pixels arranged in a matrix form. Each of the pixels is supplied with a scan TFT (Thin Film Transistor) for supplying a data voltage of a data line in response to a gate signal of a gate line and an organic light emitting diode (OLED) according to a data voltage supplied to the gate electrode And a driving TFT for adjusting the amount of current to be supplied. Specifically, the driving TFT can adjust the amount of light emitted from the organic light emitting diode (OLED) by adjusting the amount of current flowing from the high potential voltage (VDD) supplied to each pixel to the organic light emitting diode (OLED).

On the other hand, the organic light emitting diode display device includes a voltage supply circuit for supplying a high potential voltage (VDD) to all the pixels of the display panel. In particular, since the conventional organic light emitting diode display device supplies a high-potential voltage (VDD) to all the pixels of the display panel using one voltage supply circuit, the high-potential voltage supply load is high. Accordingly, the conventional organic light emitting diode display device may cause not only an increase in heat generation and luminance unevenness of the display panel but also a burnt problem of the high-potential supply line.

The present invention provides an organic light emitting diode (OLED) display device and a method of driving the same that can reduce a high-potential voltage supply load.

An organic light emitting diode display according to an embodiment of the present invention includes a display panel divided into N blocks (N is a natural number of 2 or more) blocks; And a power supply circuit for supplying a high potential voltage to each of the N blocks, wherein the power supply circuit supplies a k th high potential voltage to a block k (k is a natural number satisfying 1? K? N) .

A method of driving an organic light emitting diode display according to an exemplary embodiment of the present invention includes dividing a display panel into N (N is a natural number) blocks; And supplying a high potential voltage to each of the N blocks, wherein the step of supplying a high potential voltage to each of the N blocks comprises the steps of: k (k is a natural number satisfying 1? K? N) And supplying a k th high potential voltage to the block.

The present invention can lower the high-potential voltage supply load because the pixel array of the display panel is divided into N blocks and the high-potential voltage is divided and supplied to the N blocks. As a result, the first embodiment of the present invention can reduce the heat generation of the display panel, increase the luminance uniformity, and solve the burnt problem of the high-potential supply line.

The present invention adjusts the first to Nth high potential voltages based on the sensed first to Nth currents. As a result, the present invention can minimize the deviation of the first to Nth high potential voltages supplied to the first to Nth blocks. Thus, the present invention can improve the luminance uniformity of the first to Nth blocks.

1 is a block diagram showing an organic light emitting diode display device according to a first embodiment of the present invention.
2 is a block diagram showing an organic light emitting diode display device according to a second embodiment of the present invention.
3 is a circuit diagram showing a DC voltage feedback circuit in detail;
4 is an exemplary view showing first to third feedback signals.
5 is a flowchart illustrating a method of driving an organic light emitting diode display according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The component name used in the following description may be selected in consideration of easiness of specification, and may be different from the actual product name.

1 is a block diagram showing an organic light emitting diode display device according to a first embodiment of the present invention. Referring to FIG. 1, an organic light emitting diode display device according to a first embodiment of the present invention includes a display panel 10, a gate driving circuit, a data driving circuit, a timing control circuit, a power supply circuit 170, and the like .

In the display panel 10, a data line and a gate line are formed so as to intersect with each other, and a pixel array PA in which pixels P are arranged in a matrix form in an intersecting region of the data lines and the gate lines is formed. Each of the pixels P of the display panel 10 includes at least one thin film transistor, a driving TFT, an organic light emitting diode (OLED) element, and at least one capacitor. Each of the pixels P controls an electric current flowing through the organic light emitting diode element using a switching TFT and a driving TFT to display an image. Specifically, the driving TFT can adjust the amount of current flowing from the high potential voltage supplied to each of the pixels P to the organic light emitting diode OLED, so that the amount of light emitted from the organic light emitting diode OLED can be adjusted. The display panel 10 may display an image in the form of bottom emission and top emission depending on the pixel structure.

The pixel array PA of the display panel 10 can be divided into N blocks (N is a natural number of 2 or more) blocks. 1, the pixel array PA of the display panel 10 is divided into three blocks BL1, BL2, and BL3 for convenience of explanation, but it should be noted that the present invention is not limited thereto. Each of the N blocks may be divided to include p (p is a natural number) pixels. That is, the N blocks may be divided to have the same size. Further, the N blocks may be divided in the short side direction of the display panel 10. [ For example, the N blocks may be divided in the longitudinal direction (y-axis direction) which is the short side direction of the display panel 10 as shown in Fig.

The gate drive circuit includes a plurality of gate drive integrated circuits (ICs) 110. The gate drive ICs 110 supply at least one gate pulse for controlling the at least one switching TFT of each of the pixels P to the gate lines of the display panel 10. [ The gate drive ICs 110 may be mounted on a gate TCP (tape carrier package) 111 and the gate TCP 111 may be bonded to the display panel 10 by a TAB (tape automated bonding) process. Meanwhile, the gate drive ICs 110 may be directly formed simultaneously with the pixel array PA by a GIP (gate in panel) process.

The data driving circuit includes a plurality of source drive ICs 120. [ The source drive ICs 120 receive digital image data from the timing control circuit. The source drive ICs 120 convert the digital image data into an analog data voltage in response to a source timing control signal from the timing control circuit, synchronize the data voltage with the gate pulse, . The source drive ICs 120 may be mounted on the source TCP 121 and the source TCP 121 may be bonded to the display panel 10 and the source PCB (printed circuit board) 140 by a TAB process have. Alternatively, the source drive ICs 120 may be directly bonded to the display panel 10 by a COG (chip on glass) process.

The timing control circuit receives digital image data and a timing signal from a host system (not shown). The timing signal includes a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, a dot clock, and the like. The timing control circuit generates timing control signals for controlling the operation timing of the gate drive circuit and the data drive circuit based on the digital image data and the timing signal. The timing control signals include a gate timing control signal for controlling the operation timing of the gate drive circuit, and a data timing control signal for controlling the operation timing of the data drive circuit. The timing control circuit outputs the gate timing control signal to the gate driving circuit, and outputs the digital image data and the data timing control signal to the data driving circuit. The timing control circuit may be mounted on the control PCB 160. The source PCB 140 and the control PCB 160 may be connected by a flexible printed circuit board (FPCB) 150.

The power supply circuit 170 supplies a high potential voltage to each of the N blocks. The power supply circuit 170 supplies the k th high voltage VDDk to the block k (k is a natural number satisfying 1? K? N). For example, the power supply circuit 170 supplies a first high-potential voltage VDD1 to the first block BL1 and a second high-potential voltage VDD2 to the second block BL2, And supplies the third high potential voltage VDD3 to the third block BL3. The first to Nth high potential voltages are applied from the power supply circuit 170 to the control PCB 160, the flexible printed circuit board 150, the source PCB 140, the source TCP 121 or the film on glass (FOG) 130 To the first to Nth blocks of the display panel 10. [ The FOG 130 may be bonded to the display panel 10 and the source PCB 140.

Since the source driver IC 120 is mounted on the source TCP 121, the high-potential voltage supply lines supplying the high-potential voltage on the source TCP 121 and the data links connected to the data lines are formed to overlap with each other . In this case, a short between the high potential supply lines and the data links may occur due to foreign objects and process errors, which may cause a burnt problem in the high potential supply lines. In order to prevent this, the first to Nth high potential voltages may be supplied to the display panel 10 through the FOG 130 as well as the source TCP 121 as shown in FIG. In this case, since the first to Nth high potential voltages are supplied divided into the source TCP 121 and the FOG 130, a short between the high potential supply lines and the data links on the source TCP 121, The possibility of occurrence can be reduced.

The power supply circuit 170 may include a high potential voltage feedback circuit 171. The high-potential voltage feedback circuit 171 senses the first to N-th currents of the first to N-th blocks through the first to N-th sensing lines connected to the first to N-th blocks. For example, as shown in FIG. 1, the first sensing line SL1 is connected to the first block BL1 to sense the first current of the first block BL1, the second sensing line SL2 is connected to the second block BL1, The third sensing line SL3 is connected to the third block BL2 to sense the second current of the second block BL2 and the third sensing line SL3 is connected to the third block BL3 to sense the third current of the third block BL3 . On the other hand, the first through N-th sensing lines may be connected to the high-potential voltage lines of the first through N-th blocks. That is, the kth sensing line may be connected to the high potential voltage line of the kth block. Further, the high-potential voltage feedback circuit 171 adjusts the first to Nth high-potential voltages based on the sensed first to Nth currents. A detailed description of the high-potential voltage feedback circuit 171 will be given later with reference to Fig.

As described above, according to the first embodiment of the present invention, since the pixel array PA of the display panel 10 is divided into N blocks and the high-potential voltage is divided and supplied to N blocks, The above voltage supply load can be lowered. As a result, the first embodiment of the present invention can reduce the heat generation of the display panel, increase the luminance uniformity, and solve the burnt problem of the high-potential supply line.

2 is a block diagram showing an organic light emitting diode display device according to a second embodiment of the present invention. Referring to FIG. 2, the organic light emitting diode display device according to the second embodiment of the present invention includes a display panel 10, a gate driving circuit, a data driving circuit, a timing control circuit, a power supply circuit 170, and the like .

The pixel array PA of the display panel 10 can be divided into N blocks (N is a natural number of 2 or more) blocks. 2, the pixel array PA of the display panel 10 is divided into three blocks BL1, BL2, and BL3. However, the present invention is not limited thereto. N blocks may be divided in the long side direction of the display panel 10. [ For example, N blocks may be divided in the horizontal direction (x-axis direction) which is the long side direction of the display panel 10 as shown in Fig.

In addition, the organic light emitting diode display according to the second embodiment of the present invention may be substantially the same as the organic light emitting diode display according to the first embodiment of the present invention described with reference to FIG. Therefore, a detailed description of the organic light emitting diode display according to the second embodiment of the present invention will be omitted.

3 is a circuit diagram showing the high-potential voltage feedback circuit in detail. 3, the high-potential voltage feedback circuit 171 includes a feedback control signal output section 171a, a high-potential voltage regulating section 171b, a switch circuit SW, and the like. 3, the first through third transistors T1, T2, and T3 of the switch circuit SW are N-type transistors. However, the present invention is not limited thereto. The first to third transistors T1, T2, and T3 of the switch circuit SW may be implemented as a P type. In addition, the first to third transistors T1, T2, and T3 of the switch circuit SW may be implemented as a switch. Meanwhile, the feedback control signal output unit 171a and the high-potential-voltage adjusting unit 171b may be configured as one unit.

The feedback control signal output section 171a outputs first to Nth feedback control signals for controlling the switch circuit SW. 4 is an exemplary view showing first to third feedback signals. Referring to FIG. 4, the feedback control signal output unit 171a generates pulses of the first to Nth feedback control signals. In FIG. 4, the feedback control signal output section 171a generates pulses of the first to Nth feedback control signals in different periods. For example, the feedback control signal output unit 171a may sequentially generate the pulses of the first to third feedback control signals FC1, FC2, and FC3 as shown in FIG. That is, the feedback control signal output section 171a generates the pulse of the first feedback control signal FC1 during the first period t1 and the pulse of the second feedback control signal FC2 during the second period t2 And generate a pulse of the third feedback control signal FC3 during the third period t3. Since the first to third transistors T1, T2 and T3 of the switch circuit SW are implemented as N types in FIG. 3, the pulse of the first to Nth feedback control signals in FIG. 4 is the gate high voltage VGH, As shown in Fig.

The switch circuit SW connects the first to Nth sensing lines to the resistance group RG in response to the first to Nth feedback control signals of the feedback control signal output section 171a. The switch circuit SW may include first to Nth transistors. The k-th transistor couples the kth sensing line of the k-th block to the k-th resistor in response to the k-th feedback control signal of the k-th feedback control line (FLk). Therefore, the kth current flowing through the kth sensing line can be sensed by the high potential adjusting unit 171b. For example, the first transistor T1 is connected to the first sensing line SL1 of the first block BL1 in response to a pulse of the first feedback control signal FC1 of the first feedback control line FL1, And is connected to the resistor R1. Accordingly, the high-potential-voltage regulator 171b can sense the first current flowing through the first sensing line SL1 during the first period t1.

In particular, the high-potential-voltage regulator 171b can sense the first to Nth currents by switching the switch circuit SW. Specifically, when the feedback control signal output section 171a sequentially generates pulses of the first to Nth feedback control signals, the high-potential-voltage adjusting section 171b controls the high-potential voltage adjusting section 171b by switching the switch circuit SW 1 < / RTI > to N currents can be sequentially sensed. For example, referring to FIGS. 3 and 4, since the first transistor T1 is turned on in response to the pulse of the first feedback control signal FC1 during the first period t1, the high- 171b can sense the first current of the first block BL1. The second transistor T2 is turned on in response to the pulse of the second feedback control signal FC2 during the second period t2 so that the high potential voltage regulator 171b outputs the second current of the second block BL2 Can be sensed. The third transistor T3 is turned on in response to the pulse of the third feedback control signal FC3 during the third period t3 so that the high potential voltage regulator 171b outputs the third current of the third block BL3 Can be sensed.

The high-potential-voltage adjuster 171b adjusts the high-potential voltage supplied to the block having the minimum current value among the first to Nth currents. For example, if the first current is the minimum current value, the high-potential voltage regulator 171b may determine that the first high-potential voltage VDD1 supplied to the first block BL1 is lower than the high- Level, the first high-potential voltage VDD1 supplied to the first block BL1 is adjusted upward. Alternatively, the high-potential-voltage adjusting unit 171b adjusts the high-potential voltage supplied to the block having the maximum current value among the first to Nth currents to be downwardly adjusted. For example, if the second current is the maximum current value, the high-potential voltage regulator 171b may determine that the second high-potential voltage VDD2 supplied to the second block BL2 is higher than the high-potential voltages supplied to the other blocks Level, the second high-potential voltage VDD2 supplied to the second block BL2 is adjusted downward. As a result, the present invention can minimize the deviation of the first to Nth high potential voltages supplied to the first to Nth blocks. Thus, the present invention can improve the luminance uniformity of the first to Nth blocks.

In FIG. 4, the feedback control signal output unit 171a generates pulses of the first to Nth feedback control signals in different periods. However, it should be noted that the present invention is not limited thereto. For example, the feedback control signal output section 171a may simultaneously generate pulses of the first to Nth feedback control signals. In this case, the high-potential-voltage adjusting unit 171b may simultaneously sense the first to Nth currents.

5 is a flowchart illustrating a method of driving an organic light emitting diode display according to an exemplary embodiment of the present invention. Referring to FIG. 5, a method of driving an organic light emitting diode display according to an embodiment of the present invention includes first through fourth steps (S101 through S104).

In the first step S101, the pixel array PA of the display panel 10 is divided into N blocks. At this time, each of the N blocks may be divided to include p pixels. That is, the N blocks may be divided to have the same size. Further, the N blocks may be divided in the short side direction of the display panel 10. [ For example, the N blocks may be divided in the longitudinal direction (y-axis direction) which is the short side direction of the display panel 10 as shown in Fig. In addition, N blocks may be divided in the long side direction of the display panel 10. [ For example, N blocks may be divided in the horizontal direction (x-axis direction) which is the long side direction of the display panel 10 as shown in Fig. It should be noted that the number of blocks and the dividing direction can be determined in advance through a preliminary experiment. (S101)

The second step S102 supplies a high potential voltage to each of the N blocks using the power supply circuit 170. [ The second step S102 supplies the k-th high-potential voltage VDDk to the k-th block using the power supply circuit 170. [ For example, the power supply circuit 170 supplies a first high-potential voltage VDD1 to the first block BL1 and a second high-potential voltage VDD2 to the second block BL2, And supplies the third high potential voltage VDD3 to the third block BL3. (S102)

The third step S103 senses the first to Nth currents of the first to Nth blocks through the first to the N-th sensing lines connected to the first to Nth blocks. For example, as shown in FIG. 1, the first sensing line SL1 is connected to the first block BL1 to sense the first current of the first block BL1, the second sensing line SL2 is connected to the second block BL1, And the third sensing line SL3 is connected to the third block BL3 and senses the third current of the third block BL3 by sensing the second current of the second block BL2, . Specifically, the third step S103 can sense the first to Nth currents by switching of the switch circuit SW, which has already been described in detail earlier in conjunction with FIG. 3 and FIG. (S103)

The fourth step S104 adjusts the first to Nth high potential voltages based on the sensed first to Nth currents. Specifically, the fourth step S104 adjusts the high potential voltage supplied to the block having the minimum current value among the first to Nth currents. Alternatively, the fourth step S104 adjusts the high potential voltage supplied to the block having the maximum current value among the first to Nth currents. A detailed description thereof has already been described in detail in conjunction with FIG. 3 and FIG. (S104)

As described above, since the pixel array of the display panel is divided into N blocks and the high-potential voltage is divided and supplied to the N blocks, the high-potential voltage supply load can be lowered . As a result, the first embodiment of the present invention can reduce the heat generation of the display panel, increase the luminance uniformity, and solve the burnt problem of the high-potential supply line.

The present invention adjusts the first to Nth high potential voltages based on the sensed first to Nth currents. As a result, the present invention can minimize the deviation of the first to Nth high potential voltages supplied to the first to Nth blocks. Thus, the present invention can improve the luminance uniformity of the first to Nth blocks.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the 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.

10: Display panel 110: Gate drive IC
111: Gate TCP 120: Source drive IC
121 Source TCP 130: FOG
140: source PCB 150: flexible printed circuit board
160: Control PCB 170: Power supply circuit
171: High potential voltage feedback circuit 171a: Feedback control signal output section
171b: High-potential-difference voltage adjusting section SW: Switch circuit
PA: pixel array

Claims (19)

A display panel divided into N blocks (N is a natural number of 2 or more) blocks; And
And a power supply circuit for supplying a high potential voltage to each of the N blocks,
Wherein the power supply circuit supplies a k th high potential voltage to a kth block (k is a natural number satisfying 1? K? N), senses first to Nth currents of the first to Nth blocks, To the N-th currents, or adjusts the high-potential voltage supplied to the block having the maximum current value to be downwardly adjusted. The method according to claim 1,
Wherein each of the N blocks comprises:
and p (p is a natural number) pixels. The method according to claim 1,
N blocks,
Wherein the organic light emitting diode display panel is divided in the short side direction of the display panel. The method according to claim 1,
N blocks,
Wherein the organic light emitting diode display panel is divided into a long side direction of the display panel. The method according to claim 1,
The power supply circuit includes:
And a high potential voltage feedback circuit for sensing the first to Nth currents of the first to Nth blocks and adjusting the first to Nth high potential voltages based on the first to Nth currents. The organic light emitting diode display device. 6. The method of claim 5,
The high-potential voltage feedback circuit includes:
A feedback control signal output unit for outputting first to Nth feedback control signals for controlling the switch circuit; And
Sensing the first through Nth currents, adjusting a high potential voltage supplied to a block having a minimum current value among the first through N th currents, or adjusting a high potential voltage supplied to a block having a maximum current value And a high-potential voltage regulator for regulating the voltage of the organic light-emitting diode. The method according to claim 6,
The switch circuit includes:
And connects the first to the N-th sensing lines to the resistance group in response to the first to N-th feedback control signals. 8. The method of claim 7,
The switch circuit includes:
And first to N-th transistors turned on in response to the first to N-th feedback control signals. The method according to claim 6,
Wherein the first to N-th feedback control signals generate pulses in different periods. The method according to claim 6,
Wherein the first to N-th feedback control signals generate pulses at the same time. Dividing the display panel into N (N is a natural number) blocks; And
And supplying a high potential voltage to each of the N blocks,
Wherein supplying the high potential voltage to each of the N blocks comprises:
Supplying a k th high voltage to a kth block (k is a natural number satisfying 1? K? N); And
The first to Nth currents of the first to Nth blocks are sensed to adjust the high potential voltage supplied to the block having the minimum current value among the first to Nth currents or to supply the block having the maximum current value And lowering a high-potential voltage of the organic light emitting diode display device. 12. The method of claim 11,
The step of dividing the display panel into N (N is a natural number)
Wherein each of the N blocks is divided so as to include p pixels (p is a natural number) pixels. 12. The method of claim 11,
The step of dividing the display panel into N (N is a natural number)
And each of the N blocks is divided in the short side direction of the display panel. 12. The method of claim 11,
The step of dividing the display panel into N (N is a natural number)
Wherein each of the N blocks is divided into a long side direction of the display panel. delete 12. The method of claim 11,
Sensing the first through N th currents of the first through N th blocks and adjusting the first through N th high voltage based on the first through N th currents,
Outputting first to N-th feedback control signals for controlling the switch circuit; And
Sensing the first through Nth currents, adjusting a high potential voltage supplied to a block having a minimum current value among the first through N th currents, or adjusting a high potential voltage supplied to a block having a maximum current value And driving the organic light emitting diode display device. 17. The method of claim 16,
Sensing the first through N th currents of the first through N th blocks and adjusting the first through N th high voltage based on the first through N th currents,
And sensing the first through Nth currents by connecting the first through Nth sensing lines to the resistance group in response to the first through Nth feedback control signals. . 17. The method of claim 16,
Wherein the first to N-th feedback control signals generate pulses in different periods. 17. The method of claim 16,
Wherein the first to Nth feedback control signals generate pulses at the same time.

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