KR20080003995A - Light-emitting device and method of driving the same - Google Patents

Abstract

A light emitting device and a method of driving the same are provided to prevent crosstalk by equalizing discharge voltages with an average value of cathode voltages of pixels. A light emitting device includes data and scan lines(D1-D4,S1-S4), plural pixels(E11-E44), and a discharge unit(306). The data and scan lines are arranged in first and second directions, respectively. The pixels are formed at areas, which are defined by crossing with the data and scan lines. The discharge unit, which includes a sub-discharge unit(320) and switches(SW1-SW4), discharges the data lines up to a discharge voltage corresponding to the cathode voltage of one pixel among pixels corresponding to one scan line. The sub-discharge unit supplies a voltage corresponding to the discharge voltage to the data lines. The switches switch the data lines and sub-discharge unit.

Description

LIGHT-EMITTING DEVICE AND METHOD OF DRIVING THE SAME}

1 is a block diagram showing a conventional light emitting device.

2A and 2B are circuit diagrams schematically illustrating the light emitting device of FIG. 1.

2C is a timing diagram showing a driving process of the light emitting device.

3 is a block diagram showing a light emitting device according to a first embodiment of the present invention.

4A and 4B are circuit diagrams schematically illustrating the light emitting device of FIG. 3.

4C is a timing diagram showing a driving process of the light emitting device.

5 is a circuit diagram showing a light emitting device according to a second preferred embodiment of the present invention.

6 is a block diagram showing a light emitting device according to a third embodiment of the present invention.

7A to 7C are circuit diagrams illustrating the light emitting device of FIG. 6.

8 is a view showing a light emitting device according to a fourth preferred embodiment of the present invention.

9 is a block diagram showing a light emitting device according to a fifth embodiment of the present invention.

The present invention relates to a light emitting device and a method of driving the same, and more particularly, to a light emitting device and a method of driving the cross-talk phenomenon (Cross-talk Phenomenon) does not occur.

The light emitting device generates light having a predetermined wavelength when a predetermined voltage or a predetermined current is provided. In particular, the organic light emitting device is a self-light emitting device.

1 is a view showing a conventional light emitting device.

Referring to FIG. 1, a conventional light emitting device includes a panel 100, a controller 102, a scan driver 104, a discharge unit 106, a precharge unit 108, and a data driver 110.

The panel 100 includes a plurality of pixels E11 to E44 formed in light emitting regions where the data lines D1 to D4 and the scan lines S1 to S4 cross each other.

The controller 102 receives display data from an external device (not shown), and uses the received display data to scan the scan driver 104, the discharge unit 106, the precharge unit 108, and the data driver 110. To control the operation.

The scan driver 104 transmits scan signals to the scan lines S1 to S4. As a result, the scan lines S1 to S4 are sequentially connected to ground as detailed below.

The discharge unit 106 includes a Zener diode ZD, a Zener diode ZD, and switches SW1 to SW4 for switching the data lines D1 to D4. Thus, the discharge unit 106 discharges the data lines D1 to D4 equally to the discharge voltage corresponding to the zener voltage of the zener diode ZD during the discharge time.

The precharge unit 108 provides precharge currents to the data lines D1 to D4 discharged by the discharge unit 106 to precharge the data lines D1 to D4.

The data driver 110 provides data currents corresponding to the display data to the data lines D1 to D4 under the control of the controller 102.

2A and 2B are schematic circuit diagrams illustrating the light emitting device of FIG. 1, and FIG. 2C is a timing diagram illustrating a driving process of the light emitting device. Hereinafter, a driving process of the light emitting device will be described in detail with reference to FIGS. 2A to 2C.

First, the switches SW1 to SW4 are turned on. In this case, the scan lines S1 to S4 are connected to a non-light emitting source having a voltage V2 having the same magnitude as the driving voltage Vcc of the light emitting device. As a result, the data lines D1 to D4 are discharged to the first discharge voltage having the same magnitude during the first discharge time dcha1.

Subsequently, the switches SW1 to SW4 are turned off.

Subsequently, precharge currents output from the precharge unit 108 are provided to the data lines D1 to D4 for the first precharge time pcha1, so that the data lines D1 to D4 are precharged. .

Thereafter, the data currents I11 to I41 output from the data driver 110 are provided to the data lines D1 to D4 during the first emission time t1 as shown in FIG. 2A. In this case, the first scan line S1 is connected to ground, and the remaining scan lines S2 to S4 are connected to the non-light emitting source. Accordingly, data currents I11 to I41 flow to the ground through the data lines D1 to D4, the pixels E11 to E41, and the first scan line S1, and as a result, the first scan line S1. Pixels E11 to E41 related to the light emission.

Subsequently, the switches SW1 to SW4 are turned on. In this case, the scan lines S1 to S4 are connected to the non-light emitting source. As a result, the data lines D1 to D4 are equally discharged to the second discharge voltage corresponding to the zener voltage of the zener diode ZD during the second discharge time dcha2.

Subsequently, the switches SW1 to SW4 are turned off.

Then, the precharge currents output from the precharge unit 108 are provided to the data lines D1 to D4 for the second precharge time pcha2, so that the data lines D1 to D4 are precharged. .

Thereafter, the data currents I12 to I42 output from the data driver 110 are provided to the data lines D1 to D4 as shown in FIG. 2B during the second light emission time t2. In this case, the second scan line S2 is connected to the ground, and the remaining scan lines S1, S3, and S4 are connected to the non-light emitting source. Accordingly, data currents I12 to I42 flow to the ground through data lines D1 to D4, pixels E12 to E42, and second scan line S2, and as a result, second scan line S2. Pixels E12 to E42 related to the light emission.

The above light emission process is repeated to the fourth scan line S4, that is, after the light emission process is finished for one frame, the above light emission process from the first scan line S1 to the scan lines S1 to S4 is performed. The light emission process is repeated in units.

Hereinafter, the luminance of the pixels E11 and E12 will be compared with reference to FIGS. 2A to 2C. However, the data currents I11 to I41 are 3A, 0A, 3A, and 3A, respectively, as shown in FIG. 2A, and the data currents I12 to I42 are all 3A, as shown in FIG. 2B.

Since the luminance of the pixels E11 and E12 is influenced by the cathode voltages VC11 and VC12 of the pixels E11 and E12, first, the pixels E11 to E42 corresponding to the scan lines S1 and S2. We will look at the cathode voltages VC11 to VC42.

The resistance between the pixel E11 and the ground is the scan resistance R _S , and the resistance between the pixel E21 and the ground is R _S + R _P. Further, the resistance between the pixel E31 and the ground is R _S + 2R _P , and the resistance between the pixel E41 and the ground is R _S + 3R _P.

Here, since the cathode voltage has a value corresponding to the product of the resistance between the pixel and the ground and the current flowing through the scan line, the cathode voltage VC11 of the pixel E11 is shown in FIG. 9A (3A + 0A + 3A + 3A) × (R _S )], and the cathode voltage VC21 of the pixel E21 is [9A (3A + 0A + 3A + 3A) × (R _S ) + 6A (0A + 3A + 3A) x R _P ]. In addition, the cathode voltage VC31 of the pixel E31 is [9A (3A + 0A + 3A + 3A) × (R _S ) + 6A (0A + 3A + 3A) × R _P + 6A (3A + 3A) × R _P ], and the cathode voltage VC41 of the pixel E41 is [9A (3A + 0A + 3A + 3A) × (R _S ) + 6A (0A + 3A + 3A) × R _P + 6A (3A + 3A) X R _P +3 A x R _P ].

Hereinafter, when the cathode voltages VC12 to VC42 of the pixels E12 to E42 related to the second scan line S2 are obtained, the cathode voltage VC12 of the pixel E12 is as shown in FIG. 2B. 12A (3A + 3A + 3A + 3A) × (R _S )], and the cathode voltage VC22 of the pixel E22 is [12A (3A + 3A + 3A + 3A) × (R _S ) + 9A (3A + 3A + 3A) x R _P ]. In addition, the cathode voltage VC32 of the pixel E32 is [12A (3A + 3A + 3A + 3A) × (R _S ) + 9A (3A + 3A + 3A) × R _P + 6A (3A + 3A) × R _P ], and the cathode voltage VC42 of the pixel E42 is [12A (3A + 3A + 3A + 3A) × (R _S ) + 9A (3A + 3A + 3A) × R _P + 6A (3A + 3A) X R _P +3 A x R _P ].

Hereinafter, the luminance of the pixels E11 and E12 will be compared.

Since the total current value 9A flowing in the first scan line S1 is smaller than the total current value 12A flowing in the second scan line S2 and its resistance is the same, the pixel corresponding to the first scan line S1 is the same. The cathode voltage VC11 of E11 is smaller than the cathode voltage VC12 of the pixel E12 corresponding to the second scan line S2.

In this case, the data line D1 corresponding to the pixels E11 and E12 is discharged to the discharge voltage corresponding to the zener voltage of the zener diode ZD during the first and second emission times dcha1 and dcha2. That is, the first discharge voltage has the same magnitude as the second discharge voltage as shown in FIG. 2C. Therefore, when the data currents I11 and I12 of the same magnitude 3A are provided to the data line D1, the anode voltages VA11 and VA12 of the pixels E11 and E12 are the cathode voltages VC11 and It rises from VC12 to voltages of a predetermined magnitude and then stabilizes. Here, the amount of charge consumed until the anode voltage VA12 of the pixel E12 is stabilized is greater than the amount of charge consumed until the anode voltage VA11 of the pixel E11 is stabilized, as shown in FIG. 2C. Therefore, the luminance VA12-VC12 of the pixel E12 is smaller than the luminance VA11-VC11 of the pixel E11.

In short, the luminance of the pixels E11 to E44 varies with its cathode voltage, so that a luminance difference also occurs between pixels to which data currents of the same magnitude are provided to emit light with the same luminance. This phenomenon is called a cross-talk phenomenon.

It is an object of the present invention to provide a light emitting device in which a cross-talk phenomenon does not occur and a method of constructing the same.

In order to achieve the above object, a light emitting device according to an exemplary embodiment of the present invention includes data lines, scan lines, a plurality of pixels, and a discharge unit. The data lines are arranged in a first direction, and the scan lines are arranged in a second direction different from the first direction. The pixels are formed in regions where the data lines and the scan lines intersect. The discharge unit discharges the data lines up to a discharge voltage corresponding to a cathode voltage of one pixel among pixels corresponding to one scan line.

The light emitting device according to another exemplary embodiment of the present invention includes data lines, scan lines, pixels, and a discharge unit. The data lines are arranged in a first direction, and the scan lines are arranged in a second direction different from the first direction. The pixels are formed in regions where the data lines and the scan lines intersect. The discharge unit discharges the data lines to a discharge voltage corresponding to an average value of cathode voltages of pixels corresponding to one scan line.

The light emitting device according to another preferred embodiment of the present invention includes data lines, scan lines, a plurality of pixels, a discharge part and a data driver. The data lines are arranged in a first direction, and the scan lines are arranged in a second direction different from the first direction. The pixels are formed in regions where the data lines and the scan lines intersect. The discharge unit discharges the data lines to the first discharge voltage during the first discharge time and to the second discharge voltage during the second discharge time. The data driver provides first data currents to data lines discharged to the first discharge voltage and second data currents to data lines discharged to the second discharge voltage. Here, when the sum of the first data currents and the sum of the second data currents are different, the first discharge voltage has a different magnitude from the second discharge voltage.

An electroluminescent device according to a preferred embodiment of the present invention includes data lines, scan lines and pixels. The data lines are arranged in a first direction, and the scan lines are arranged in a second direction different from the first direction. The pixels are formed in regions where the data lines and the scan lines intersect. Here, the anode voltages of pixels corresponding to one scan line of the scan lines have a voltage corresponding to the cathode voltage and display data of one pixel of the pixels.

An electroluminescent device according to another preferred embodiment of the present invention includes data lines, scan lines and pixels. The data lines are arranged in a first direction, and the scan lines are arranged in a second direction different from the first direction. The pixels are formed in regions where the data lines and the scan lines intersect. Here, the anode voltages of pixels corresponding to one scan line of the scan lines have an average cathode voltage value of the cathode voltages of the pixels and a voltage corresponding to display data.

According to a preferred embodiment of the present invention, a method of driving a light emitting device including a plurality of pixels formed in light emitting regions where data lines and scan lines cross each other may include driving the data lines to a first discharge voltage during a first discharge time. Discharging up to; Providing first data currents to data lines discharged to the first discharge voltage; Discharging the data lines provided with the first data currents to a second discharge voltage for a second discharge time; And providing second data currents to data lines discharged to the second discharge voltage. Here, when the sum of the first data currents and the sum of the second data currents are different, the first discharge voltage has a different magnitude from the second discharge voltage.

According to another exemplary embodiment of the present invention, a method of driving a light emitting device including a plurality of pixels formed in light emitting regions where data lines and scan lines intersect is provided, wherein the data lines correspond to cathodes of pixels corresponding to one scan line. Providing a predetermined voltage to the data lines to discharge up to a discharge voltage corresponding to an average value of the voltages; And providing data currents to the data lines.

In the light emitting device and the method of driving the light emitting device according to the present invention, since the discharge voltages have a magnitude corresponding to the average value of the cathode voltage of the one pixel or the cathode voltage of the pixels, the cross-talk phenomenon in the light emitting device of the present invention It does not occur.

Hereinafter, exemplary embodiments of a light emitting device and a method of driving the same according to the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 3, the light emitting device of the present invention includes a panel 300, a controller 302, a scan driver 304, a discharge unit 306, a precharge unit 308, and a data driver 310.

The light emitting device according to the preferred embodiment of the present invention includes an organic electroluminescent device (PDP), a plasma dispaly panel (PDP), a liquid crystal display (LCD), and the like. However, hereinafter, the organic EL device will be described as an example for convenience of description.

The panel 300 includes a plurality of pixels E11 to E44 formed in emission areas where the data lines D1 to D4 and the scan lines S1 to S4 cross each other.

Each of the pixels E11 to E44 includes an anode electrode layer, an organic material layer, and a cathode electrode layer sequentially formed on a substrate.

The controller 302 receives display data, for example, RGB data, from an external device (not shown), and uses the received display data to scan the scan unit 304, the discharge unit 306, and the free unit. The operations of the charge unit 308 and the data driver 310 are controlled. In addition, the controller 302 may store the received display data in its internal memory.

The scan driver 304 is electrically connected to the scan lines S1 to S4 and transmits scan signals to the scan lines S1 to S4. As a result, the scan lines S1 to S4 are connected to the light emitting source as described below in detail.

The discharge unit 306 provides a predetermined voltage to the data lines D1 to D4 to discharge the data lines D1 to D4 to a discharge voltage corresponding to a cathode voltage of one pixel among pixels associated with one scan line. The device includes a plurality of switches SW1 to SW4 and a sub discharge part 320.

According to another embodiment of the present invention, the discharge unit 306 discharges the data lines D1 to D4 to a discharge voltage corresponding to the average value of the cathode voltages of the pixels related to one scan line.

As illustrated in FIG. 3, the sub discharge unit 320 is connected to the data lines D1 to D4 through the switches SW1 to SW4 and provides a predetermined voltage to the data lines D1 to D4 to provide data. The lines D1 to D4 are discharged to a predetermined discharge voltage.

A detailed description of the sub discharge unit 320 will be described below with reference to the accompanying drawings.

The precharge unit 308 precharges the data lines D1 to D4 by providing precharge currents to the data lines D1 to D4 discharged by the discharge unit 306.

The data driver 310 includes a plurality of current sources IS1 to IS4, and under the control of the controller 302, data currents corresponding to the display data and output data currents output from the current sources IS1 to IS4. To D4).

4A and 4B are schematic circuit diagrams illustrating the light emitting device of FIG. 3, and FIG. 4C is a timing diagram illustrating a driving process of the light emitting device.

Referring to FIG. 4A, the sub discharge unit 320 includes switches SW5 and 400, a first digital-analog converter 402 and a DAC, and an op amp 404.

Hereinafter, a driving process of the light emitting device will be described in detail with reference to FIGS. 4A to 4C.

First, the switches SW1 to SW4 are turned on. In this case, the scan lines S1 to S4 are connected to a non-light emitting source having a voltage V2 having the same magnitude as the driving voltage Vcc of the light emitting device.

Subsequently, the DAC 402 outputs a first level voltage according to an external voltage V3 input from the outside, and the output first level voltage is input to the operational amplifier 404.

Subsequently, the operational amplifier 404 provides the first operational amplifier output voltage to the data lines D1 to D4 according to the input first level voltage, so that the data lines D1 to D4 are discharged first. During the time dcha1, it is discharged to a first discharge voltage corresponding to the first op amp output voltage. However, the first discharge voltage is a voltage corresponding to the cathode voltage of one pixel among the pixels E11 to E41 corresponding to the scan line S1.

In the light emitting device according to another embodiment of the present invention, the data lines D1 to D4 correspond to the average values of the cathode voltages VC11 to VC41 of the pixels E11 to E41 corresponding to the scan line S1. Discharge up to the discharge voltage.

Subsequently, the switches SW1 to SW4 are turned off.

Then, the precharge currents output from the precharge unit 308 are provided to the data lines D1 to D4 for the first precharge time pcha1, so that the data lines D1 to D4 are precharged. .

Subsequently, the data currents I11 to I41 output from the data driver 310 are provided to the data lines D1 to D4 during the first emission time t1 as shown in FIG. 4A. In this case, the first scan line S1 is connected to a light emitting source, preferably ground, and the remaining scan lines S2 to S4 are connected to the non-light emitting source. Accordingly, data currents I11 to I41 flow through the data lines D1 to D4, the pixels E11 to E41 and the first scan line S1 to the light emitting source, for example, the ground, and as a result, The pixels E11 to E41 related to the first scan line S1 emit light.

Subsequently, the switches SW1 to SW4 are turned on. In this case, the scan lines S1 to S4 are connected to the non-light emitting source.

Thereafter, the DAC 402 outputs a second level voltage according to an external voltage V4 input from the outside, and the output second level voltage is input to the operational amplifier 404.

Subsequently, the op amp 404 provides a second op amp output voltage to the data lines D1 to D4 in accordance with the input second level voltage, so that the data lines D1 to D4 are second discharged. During the time dcha2, it is discharged to a second discharge voltage corresponding to the second op amp output voltage. However, the second discharge voltage is a voltage corresponding to the cathode voltage of one pixel among the pixels E12 to E42 corresponding to the scan line S2.

In the light emitting device according to another embodiment of the present invention, the data lines D1 to D4 correspond to the average values of the cathode voltages VC12 to VC42 of the pixels E12 to E42 corresponding to the scan line S2. Discharge up to the discharge voltage.

Subsequently, the switches SW1 to SW4 are turned off.

Subsequently, precharge currents output from the precharge unit 308 are provided to the data lines D1 to D4 for the second precharge time pcha2, so that the data lines D1 to D4 are precharged. .

Thereafter, the data currents I12 to I42 output from the data driver 310 are provided to the data lines D1 to D4 as shown in FIG. 4B during the second emission time t2. In this case, the second scan line S2 is connected to the light emitting source, and the remaining scan lines S1, S3 and S4 are connected to the non-light emitting source. Accordingly, data currents I12 to I42 flow to the ground through the data lines D1 to D4, the pixels E12 to E42, and the second scan line S2, and as a result, the second scan line S2. Pixels E12 to E42 related to the light emission.

The above light emission process is repeated to the fourth scan line S4, that is, after the light emission process is finished for one frame, the above light emission process from the first scan line S1 to the scan lines S1 to S4 is performed. The light emission process is repeated in units.

Hereinafter, the luminance of the pixels E11 and E12 will be compared with reference to FIGS. 4A to 4C. However, the data currents I11 to I41 are 3A, 0A, 3A, and 3A, respectively, as shown in FIG. 4A, and the data currents I12 to I42 are all 3A, as shown in FIG. 4B.

Since the luminance of the pixels E11 and E12 is influenced by the cathode voltages VC11 and VC12 of the pixels E11 and E12, first, the pixels E11 to E42 corresponding to the scan lines S1 and S2. We will look at the cathode voltages VC11 to VC42 and corresponding discharge voltages.

The resistance between the pixel E11 and the ground is the scan resistance R _S , and the resistance between the pixel E21 and the ground is R _S + R _P. Further, the resistance between the pixel E31 and the ground is R _S + 2R _P , and the resistance between the pixel E41 and the ground is R _S + 3R _P.

Here, since the cathode voltage has a value corresponding to the product of the resistance between the pixel and the ground and the current flowing through the scan line, the cathode voltage VC11 of the pixel E11 is shown in FIG. 9A (3A + 0A + 3A + 3A) × (R _S )], and the cathode voltage VC21 of the pixel E21 is [9A (3A + 0A + 3A + 3A) × (R _S ) + 6A (0A + 3A + 3A) x R _P ]. In addition, the cathode voltage VC31 of the pixel E31 is [9A (3A + 0A + 3A + 3A) × (R _S ) + 6A (0A + 3A + 3A) × R _P + 6A (3A + 3A) × R _P ], and the cathode voltage VC41 of the pixel E41 is [9A (3A + 0A + 3A + 3A) × (R _S ) + 6A (0A + 3A + 3A) × R _P + 6A (3A + 3A) X R _P +3 A x R _P ]. Here, the first discharge voltage is equal to one of the cathode voltages VC11 to VC41 of the pixels E11 to E41 related to the first scan line S1, for example, VC31 as shown in FIG. 4C. Have a corresponding size. Alternatively, the first discharge voltage has a magnitude corresponding to an average value of the cathode voltages VC11 to VC41.

Hereinafter, when the cathode voltages VC12 to VC42 of the pixels E12 to E42 related to the second scan line S2 are obtained, the cathode voltage VC12 of the pixel E12 is as shown in FIG. 4B. 12A (3A + 3A + 3A + 3A) × (R _S )], and the cathode voltage VC22 of the pixel E22 is [12A (3A + 3A + 3A + 3A) × (R _S ) + 9A (3A + 3A + 3A) x R _P ]. In addition, the cathode voltage VC32 of the pixel E32 is [12A (3A + 3A + 3A + 3A) × (R _S ) + 9A (3A + 3A + 3A) × R _P + 6A (3A + 3A) × R _P ], and the cathode voltage VC42 of the pixel E42 is [12A (3A + 3A + 3A + 3A) × (R _S ) + 9A (3A + 3A + 3A) × R _P + 6A (3A + 3A) X R _P +3 A x R _P ]. Here, the second discharge voltage has a magnitude corresponding to one of the cathode voltages VC12 to VC42 of the pixels E12 to E42 related to the second scan line S2, for example, VC32. Alternatively, the second discharge voltage has a magnitude corresponding to the average value of the cathode voltages VC12 to VC42. In this case, since the average value of the cathode voltages VC12 to VC42 is larger than the average value of the cathode voltages VC11 to VC41, the second discharge voltage is higher than the first discharge voltage as shown in FIG. 4C. Have Preferably, the second discharge voltage has a magnitude larger by ΔV1 than the first discharge voltage.

In other words, the first data line D1 associated with the pixel E11 is discharged to the first discharge voltage during the first discharge time dcha1, and the first data line D1 associated with the pixel E12 is discharged to the second discharge time. Discharges to a second discharge voltage that is greater than the first discharge voltage during dcha2. That is, the controller 302 may control the external voltages V3 and V4, the DAC 402, the operational amplifier 404, and the switches SW1 to SW4 such that the data line D1 is discharged to the first and second discharge voltages. To control.

According to one embodiment of the invention, these first and second discharge voltages are set on the basis of a reference voltage of a predetermined magnitude. For example, when the reference voltage is a value corresponding to the average value of the cathode voltages of the pixels when the maximum magnitude of data currents flow through the data lines D1 to D4, the discharge voltages are the average values of the cathode voltages of the pixels. It is set by comparing with the average value corresponding to the reference voltage.

As described above, since the second discharge voltage is greater than the first discharge voltage, the data currents I11 and I12 of the same magnitude 3A are applied to the data line D1 during the emission times t1 and t2. When provided, the anode voltages VA11 and VA12 of the pixels E11 and E12 rise and stabilize from the corresponding cathode voltages VC11 and VC12 to predetermined magnitudes as shown in FIG. 4C. In this case, the amount of charge consumed until the anode voltage VA11 is stabilized is substantially the same as the amount of charge consumed until the anode voltage VA12 is stabilized, as shown in FIG. 4C. Therefore, the luminance VA11-VC11 of the pixel E11 is substantially the same as the luminance VA12-VC12 of the pixel E12, so that no cross-talk phenomenon occurs in the light emitting device of the present invention.

5 is a circuit diagram showing a light emitting device according to a second preferred embodiment of the present invention.

As shown in FIG. 5, the sub discharge unit 320 is connected to a point between the data lines D1 to D4 unlike in the first embodiment.

That is, in the light emitting device of the present invention, the sub discharge unit 320 is not limited in position as long as it is connected to the data lines D1 to D4 through the switches SW1 to SW4.

6 is a block diagram illustrating a light emitting device according to a third exemplary embodiment of the present invention, and FIGS. 7A to 7C are circuit diagrams illustrating the light emitting device of FIG. 6.

Referring to FIG. 6, the light emitting device of the present invention includes a panel 600, a controller 602, a scan driver 604, a discharge unit 606, a precharge unit 608, and a data driver 610.

Since the remaining components except for the discharge unit 606 perform the same functions as the components of the first embodiment, a description thereof will be omitted.

The discharge unit 606 includes a first sub discharge unit 620 and a second sub discharge unit 622.

The first sub discharge unit 620 discharges the data lines D1 to D4 equally to a predetermined discharge voltage. For example, as illustrated in FIGS. 7A to 7C, the first sub-discharge unit 620 may include data such as ground, a voltage source VS having a predetermined voltage, or a voltage up to a voltage corresponding to the zener diode ZD included therein. The lines D1 to D4 are discharged.

The second sub discharge part 622 compensates the cathode voltages of the pixels E11 to E44 similarly to the first embodiment.

For example, the second sub discharge unit 622 includes a switch 704, a DAC 706, and an operational amplifier 708.

In the first embodiment, since the cathode voltages VC11 to VC44 are compensated using only the current output from the operational amplifier 404, the power consumption is large. However, in the third embodiment, the data lines D1 to D4 are discharged to a predetermined discharge voltage using a zener diode ZD, etc., and then the cathode voltages VC11 to VC44 using the op amp 708. Since the light emitting device of the third embodiment has lower power consumption than the light emitting device of the first embodiment.

8 is a view showing a light emitting device according to a fourth preferred embodiment of the present invention.

Referring to FIG. 8, the light emitting device of the present invention includes a panel 800, a controller 802, a scan driver 804, a discharge unit 806, a precharge unit 808, and a data driver 810.

Since the operation of the components of the fourth embodiment is the same as the operation of the components of the first embodiment, a description thereof will be omitted.

However, unlike the light emitting device of the first embodiment, the light emitting device of the fourth embodiment is set considering the discharge voltage whose capacitance is parasitic in the pixels as well as the cathode voltages of the pixels.

9 is a block diagram illustrating a light emitting device according to a fifth exemplary embodiment of the present invention.

9, the light emitting device of the present invention includes a panel 900, a controller 902, a first scan driver 904, a second scan driver 906, a discharge unit 908, and a precharge unit 910. And a data driver 912. Since the components of the light emitting device perform functions similar to those of the first embodiment, a description thereof will be omitted.

In the light emitting device of the fifth embodiment, unlike the other embodiments in which the scan driver is formed in one direction, the scan drivers 904 and 906 are formed in both directions of the panel 900 as shown in FIG.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art having ordinary knowledge of the present invention will be able to make various modifications, changes, additions within the spirit and scope of the present invention, such modifications, changes and Additions should be considered to be within the scope of the following claims.

As described above, in the light emitting device and the method of driving the light emitting device according to the present invention, since the discharge voltage has a magnitude corresponding to the average value of the cathode voltage of one pixel or the cathode voltage of the pixels, the light emitting device of the present invention There is an advantage that no cross-talk phenomenon occurs.

Claims (23)

Data lines arranged in a first direction; Scan lines arranged in a second direction different from the first direction; A plurality of pixels formed in regions where the data lines and the scan lines cross each other; And And a discharge unit configured to discharge the data lines to a discharge voltage corresponding to a cathode voltage of one pixel among pixels corresponding to one scan line. The method of claim 1, wherein the discharge unit, A sub discharge unit providing a predetermined voltage to the data lines corresponding to the discharge voltage; And And a plurality of switches for switching the data lines and the sub discharge unit. The method of claim 2, wherein the sub discharge unit, An operational amplifier whose output is connected to a corresponding data line; And And a digital-to-analog converter (DAC) connected to an input of the op amp. The method of claim 1, wherein the discharge unit, A first sub discharge unit configured to discharge the data lines to a predetermined discharge voltage; And And a second sub discharge unit configured to provide a predetermined voltage corresponding to the discharge voltage to the data lines. The method of claim 4, wherein the first sub discharge unit, A ground connected to the data lines, The second sub discharge unit, An operational amplifier whose output is connected to a corresponding data line; And And a digital-to-analog converter (DAC) connected to an input of the op amp. The method of claim 4, wherein the first sub discharge unit, A predetermined voltage source connected to the data lines and having a predetermined voltage; The second sub discharge unit, An operational amplifier whose output is connected to a corresponding data line; And And a digital-to-analog converter (DAC) connected to an input of the op amp. The method of claim 4, wherein the first sub discharge unit, A zener diode connected to the data lines, The second sub discharge unit, An operational amplifier whose output is connected to a corresponding data line; And And a digital-to-analog converter (DAC) connected to an input of the op amp. The method of claim 1, wherein the light emitting element, A scan driver to transmit scan signals to the scan lines; And And a data driver for transmitting data signals to the data lines. The method of claim 1, wherein the light emitting element, A first scan driver to transmit first scan signals to some of the scan lines; A second scan driver to transmit second scan signals to the remaining scan lines; And And a data driver for transmitting data signals to the data lines. The light emitting device of claim 1, wherein the discharge voltage has a value corresponding to the capacitance of the capacitors and parasitic capacitors in the pixels. The light emitting device of claim 1, wherein the light emitting device is an organic electroluminescent device. Data lines arranged in a first direction; Scan lines arranged in a second direction different from the first direction; A plurality of pixels formed in regions where the data lines and the scan lines cross each other; And And a discharge unit configured to discharge the data lines to a discharge voltage corresponding to an average value of cathode voltages of pixels corresponding to one scan line. The method of claim 12, wherein the discharge unit, A sub discharge unit providing a predetermined voltage to the data lines corresponding to the discharge voltage; And And a plurality of switches for switching the data lines and the sub discharge unit. The method of claim 12, wherein the discharge unit, A first sub discharge unit configured to discharge the data lines to a predetermined discharge voltage; And And a second sub discharge unit configured to provide a predetermined voltage corresponding to the discharge voltage to the data lines. Data lines arranged in a first direction; Scan lines arranged in a second direction different from the first direction; A plurality of pixels formed in regions where the data lines and the scan lines cross each other; A discharge unit configured to discharge the data lines to a first discharge voltage during a first discharge time and to discharge to a second discharge voltage during a second discharge time; And A data driver configured to provide first data currents to data lines discharged to the first discharge voltage and to provide second data currents to data lines discharged to the second discharge voltage, And when the sum of the first data currents and the sum of the second data currents are different, the first discharge voltage has a different magnitude from the second discharge voltage. Data lines arranged in a first direction; Scan lines arranged in a second direction different from the first direction; And A plurality of pixels formed in regions where the data lines and the scan lines cross each other; And an anode voltage of pixels corresponding to one scan line of the scan lines has a voltage corresponding to a cathode voltage and display data of one pixel of the pixels. Data lines arranged in a first direction; Scan lines arranged in a second direction different from the first direction; And A plurality of pixels formed in regions where the data lines and the scan lines cross each other; And wherein the anode voltages of the pixels corresponding to one scan line of the scan lines have an average cathode voltage value of the cathode voltages of the pixels and a voltage corresponding to the display data. A method of driving a light emitting device including a plurality of pixels formed in light emitting regions where data lines and scan lines cross each other, Discharging the data lines to a first discharge voltage for a first discharge time; Providing first data currents to data lines discharged to the first discharge voltage; Discharging the data lines provided with the first data currents to a second discharge voltage for a second discharge time; And Providing second data currents to the data lines discharged to the second discharge voltage, And when the sum of the first data currents and the sum of the second data currents are different, the first discharge voltage has a different magnitude from the second discharge voltage. 19. The light emitting device of claim 18, wherein at least one of the first discharge voltage and the second discharge voltage has a magnitude corresponding to a cathode voltage of one pixel among pixels corresponding to one scan line. Driving method. 20. The light emitting device of claim 19, wherein a discharge voltage of at least one of the first discharge voltage and the second discharge voltage has a value corresponding to capacitances of capacitors parasitic in the cathode voltage and the pixels. Driving method. 19. The method of claim 18, wherein at least one of the first discharge voltage and the second discharge voltage has a magnitude corresponding to an average value of cathode voltages of pixels corresponding to one scan line. . The method of claim 18, wherein the discharging up to the first discharge voltage comprises: Providing a first voltage to the data lines, Discharging up to the second discharge voltage, And providing a second voltage to the data lines. The method of claim 22, wherein providing the first voltage or providing the second voltage comprises: Outputting a level voltage according to an external voltage; And And providing an op amp output voltage to the data lines according to the output level voltage.

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