KR102557278B1 - Pixel and organic light emitting display device having the same - Google Patents

Abstract

A pixel of the organic light emitting diode display includes an organic light emitting diode, a driving circuit that generates a driving current corresponding to a data signal and supplies the driving current to the organic light emitting diode, and a predetermined voltage level at the anode of the organic light emitting diode when driven at a low frequency. and a low-frequency compensation circuit supplying a compensation voltage to compensate for the driving current.

Description

Pixel and an organic light emitting display device including the same {PIXEL AND ORGANIC LIGHT EMITTING DISPLAY DEVICE HAVING THE SAME}

The present invention relates to a pixel and an organic light emitting display device including the same.

Recently, various flat panel display devices capable of reducing the weight and volume, which are disadvantages of cathode ray tubes, are being developed. Flat panel display devices include Liquid Crystal Display (LCD), Field Emission Display (FED), Plasma Display Panel (PDP), and Organic Light Emitting Display (OLED). ), etc. In particular, since the organic light emitting display device has various advantages such as a wide viewing angle, fast response speed, thin thickness, and low power consumption, it has been spotlighted as a promising next-generation display device. Recently, a low-frequency driving method for minimizing power consumption of an organic light emitting display device has been studied.

One object of the present invention is to provide a pixel of an organic light emitting display device that prevents image quality deterioration during low-frequency driving.

Another object of the present invention is to provide an organic light emitting display device that prevents image quality deterioration during low-frequency driving.

However, the object of the present invention is not limited to the above object, and may be expanded in various ways without departing from the spirit and scope of the present invention.

In order to achieve one object of the present invention, a pixel of an organic light emitting diode display according to embodiments of the present invention generates a driving current corresponding to an organic light emitting diode and a data signal, and supplies the driving current to the organic light emitting diode. and a low-frequency compensation circuit supplying a compensation voltage having a predetermined voltage level to an anode electrode of the organic light emitting diode to compensate for the driving current during low-frequency driving.

According to an embodiment, the low frequency compensation circuit includes a first switching circuit supplying the data signal to a first node in response to a first low frequency control signal, and a high power supply voltage in response to a second low frequency control signal. and a third switching circuit for supplying the compensation voltage to the anode electrode of the organic light emitting diode in response to the data signal or the high power supply voltage supplied to the first node. .

According to an embodiment, the first switching circuit includes a first control transistor turned on or off in response to the first low-frequency control signal, and the second switching circuit is turned on in response to the second low-frequency control signal. or a second control transistor turned off, and the third switching circuit may include a third control transistor turned on or off in response to the data signal supplied to the first node or the high power supply voltage. .

According to an embodiment, during normal driving, the first control transistor may be turned off and the second control transistor may be turned on.

According to an embodiment, the first control transistor may be turned on and the second control transistor may be turned off during the low-frequency driving.

According to one embodiment, the first switching circuit includes a first control transistor and a second control transistor turned on or off in response to the first low-frequency control signal, or a third control transistor and a fourth control transistor turned off. A control transistor, and the third switching circuit may include a fifth control transistor and a sixth control transistor turned on or off in response to the data signal or the high power supply voltage.

According to an embodiment, during normal driving, the first control transistor and the second control transistor may be turned off, and the third control transistor and the fourth control transistor may be turned on.

According to an embodiment, the transistor may be turned on, and the third control transistor and the fourth control transistor may be turned off.

In an embodiment, the fifth control transistor may be an N-channel Metal Oxide Semiconductor (NMOS) transistor, and the sixth control transistor may be a P-channel Metal Oxide Semiconductor (PMOS) transistor.

In an embodiment, the fifth control transistor may be a P-channel Metal Oxide Semiconductor (PMOS) transistor, and the sixth control transistor may be an N-channel Metal Oxide Semiconductor (NMOS) transistor.

According to an embodiment, the second switching circuit may further include a seventh control transistor and an eighth control transistor that reduce the voltage level of the data signal.

In order to achieve another object of the present invention, an organic light emitting display according to embodiments of the present invention provides a display panel including a plurality of pixels, a data driver supplying data signals to the pixels, and a scan signal to the pixels. It may include a scan driver for supplying a light emitting control unit, a light emitting control unit for supplying light emitting control signals to the pixels, and a timing control unit for generating control signals for controlling operations of the data driver, scan driver, and light emitting control unit. Each of the pixels has an organic light emitting diode, a driving circuit that generates a driving current corresponding to a data signal and supplies the driving current to the organic light emitting diode, and a predetermined voltage level at the anode electrode of the organic light emitting diode when driven at a low frequency. A low frequency compensation circuit supplying a compensation voltage to compensate for the driving current may be included.

According to an embodiment, the low frequency compensation circuit includes a first switching circuit supplying the data signal to a first node in response to a first low frequency control signal, and a high power supply voltage in response to a second low frequency control signal. and a third switching circuit for supplying the compensation voltage to the anode electrode of the organic light emitting diode in response to the data signal or the high power supply voltage supplied to the first node. .

According to an embodiment, the first switching circuit includes a first control transistor turned on or off in response to the first low-frequency control signal, and the second switching circuit is turned on in response to the second low-frequency control signal. or a second control transistor turned off, and the third switching circuit may include a third control transistor turned on or off in response to the data signal supplied to the first node or the high power supply voltage. .

According to an embodiment, during normal driving, the first control transistor may be turned off and the second control transistor may be turned on.

According to an embodiment, the first control transistor may be turned on and the second control transistor may be turned off during the low-frequency driving.

According to one embodiment, the first switching circuit includes a first control transistor and a second control transistor turned on or off in response to the first low-frequency control signal, and the second switching circuit comprises the second low-frequency control a third control transistor and fourth control transistors turned on or off in response to a signal, wherein the third switching circuit includes a fifth control transistor and a fifth control transistor turned on or off in response to the data signal or the high power supply voltage. 6 control transistors.

According to an embodiment, during normal driving, the first control transistor and the second control transistor may be turned off, and the third control transistor and the fourth control transistor may be turned on.

According to an embodiment, the first control transistor and the second control transistor may be turned on, and the third control transistor and the fourth control transistor may be turned off during the low-frequency driving.

According to an embodiment, the second switching circuit may further include a seventh control transistor and an eighth control transistor that reduce a voltage level of the data voltage.

A pixel according to embodiments of the present invention and an organic light emitting display device including the same include a low frequency compensation circuit, and supply a compensation voltage to an anode electrode of an organic light emitting diode when the organic light emitting display device is driven at a low frequency, so that a voltage is generated during low frequency driving. quality defects can be prevented. However, the effects of the present invention are not limited to the above-described effects, and may be variously extended within a range that does not deviate from the spirit and scope of the present invention.

1 is a block diagram illustrating pixels of an organic light emitting display device according to example embodiments.
FIG. 2 is a circuit diagram illustrating an example of a pixel of FIG. 1 .
3 to 5 are circuit diagrams for explaining the operation of the pixel of FIG. 2 .
6 is a circuit diagram illustrating another example of the pixel of FIG. 1 .
7 to 9 are circuit diagrams for explaining the operation of the pixel of FIG. 6 .
10 is a circuit diagram illustrating another example of the pixel of FIG. 1 .
11 is a block diagram illustrating an organic light emitting display device according to example embodiments.
FIG. 12 is a block diagram illustrating an electronic device including the organic light emitting diode display of FIG. 11 .
13 is a diagram illustrating an example in which the electronic device of FIG. 12 is implemented as a smart phone.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail. The same reference numerals are used for the same components in the drawings, and redundant descriptions of the same components are omitted.

1 is a block diagram illustrating pixels of an organic light emitting display device according to example embodiments.

Referring to FIG. 1 , the pixel PX may include an organic light emitting diode EL, a driving circuit 100 and a low frequency compensation circuit 200 .

The organic light emitting diode (EL) may include an anode electrode and a cathode electrode. The anode electrode of the organic light emitting diode (EL) is connected to the driving circuit 100 and the low frequency compensation circuit 200, and the cathode electrode of the organic light emitting diode (EL) is connected to a low power supply voltage line that supplies a low power supply voltage ELVSS. can be connected The organic light emitting diode (EL) may emit light according to a driving current flowing through an anode electrode.

The driving circuit 100 may generate a driving current corresponding to the data signal DATA and supply it to the organic light emitting diode EL. The driving circuit 100 may be connected to the scan supply line SL, the data supply line DL, and the high power voltage line ELVDD_L. The driving circuit 100 receives the data signal DATA from the data supply line DL in response to the scan signal SCAN supplied through the scan supply line SL, and receives a driving current corresponding to the data signal DATA. can create For example, the driving circuit 100 may include a switching transistor, a storage capacitor, and a driving transistor. The switching transistor may be turned on in response to the scan signal SCAN supplied through the scan supply line SL. When the switching transistor is turned on, the data signal DATA supplied through the data supply line DL may be stored in the storage capacitor. The driving transistor may generate a driving current corresponding to the data signal DATA. However, the configuration of the driving circuit 100 is not limited thereto. Hereinafter, it will be described in detail with reference to FIGS. 2 and 6 .

The low frequency compensation circuit 200 may supply a compensation voltage having a predetermined voltage level to the anode electrode of the organic light emitting diode (EL) to compensate for the driving current when the organic light emitting display device is driven at a low frequency. Leakage current may occur in the storage capacitor of the pixel PX when the organic light emitting diode display is driven at a low frequency. In this case, the data signal DATA (ie, the data voltage) may be changed, resulting in poor image quality (eg, a flicker phenomenon). The low frequency compensation circuit 200 supplies a compensation voltage to the anode electrode of the organic light emitting diode (EL) to compensate for the leakage current generated in the storage capacitor of the pixel PX during low frequency driving, thereby generating a voltage generated during low frequency driving of the organic light emitting diode display. quality defects can be prevented.

The low frequency compensation circuit 200 may be connected to the driving circuit 100 and the high power voltage line ELVDD_L. The low frequency compensation circuit 200 may include a first switching circuit 220 , a second switching circuit 240 and a third switching circuit 260 . The first switching circuit 220 may supply the data signal DATA to the first node in response to the first low frequency control signal. The second switching circuit 240 may supply the high power supply voltage ELVDD (eg, ELVDD) to the first node in response to the second low frequency control signal. The third switching circuit 260 may supply a compensation voltage to the anode electrode of the organic light emitting diode EL in response to the data signal DATA or the high power supply voltage ELVDD supplied to the first node. In this case, the first low-frequency control signal may be activated when the OLED display is driven at a low frequency, and the second low-frequency control signal may be activated when the OLED display is normally driven.

In one embodiment, the first switching circuit 220 includes a first control transistor that is turned on or off in response to a first low-frequency control signal, and the second switching circuit 240 is responsive to a second low-frequency control signal. A third control transistor is turned on or off in response to the data signal DATA or the high power supply voltage ELVDD supplied to the first node. Transistors may be included. During normal driving of the OLED display, the first control transistor may be turned off in response to the first low frequency control signal, and the second control transistor may be turned on in response to the second low frequency control signal. In this case, the high power supply voltage ELVDD is supplied to the first node through the second control transistor to turn off the third control transistor. When the organic light emitting diode display is driven at a low frequency, the first control transistor may be turned on and the second control transistor may be turned off in response to the first low frequency control signal. In this case, the data signal DATA may be supplied to the first node through the first control transistor. When the data signal DATA has a voltage level lower than the voltage level at which the third control transistor is turned on, the third control transistor is turned off and a compensation voltage having a preset voltage level is applied to the anode electrode of the organic light emitting diode EL. may not be supplied. When the data signal DATA has a higher voltage level than the voltage level at which the third control transistor is turned on, the third control transistor is turned on and a compensation voltage having a preset voltage level is supplied to the anode electrode of the organic light emitting diode EL. It can be. Accordingly, the driving current supplied to the organic light emitting diode EL may be compensated for during low-frequency driving.

In another embodiment, the first switching circuit 220 includes a first control transistor and a second control transistor that are turned on or off in response to a first low frequency control signal, and the second switching circuit 240 includes a second low frequency control transistor. The third control transistor 260 is turned on or off in response to the data signal DATA or the high power supply voltage ELVDD. A fifth control transistor and a sixth control transistor may be included. In this case, the fifth control transistor and the sixth control transistor may be turned on by signals having different voltage levels. In one embodiment, when the fifth control transistor is an N-channel Metal Oxide Semiconductor (NMOS) transistor, the sixth control transistor may be a P-channel Metal Oxide Semiconductor (PMOS) transistor. In this case, the fifth control transistor may be turned on in response to a voltage having a low level, and the sixth control transistor may be turned on in response to a voltage having a high level. In another embodiment, when the fifth control transistor is a PMOS transistor, the sixth control transistor may be an NMOS transistor. In this case, the fifth control transistor may be turned on in response to a voltage having a high level, and the sixth control transistor may be turned on in response to a voltage having a low level. During normal driving of the OLED display, the first control transistor and the second control transistor are turned off in response to the first low-frequency control signal, and the third control transistor and the fourth control transistor are turned on in response to the second low-frequency control signal. It can be. In this case, the high power supply voltage ELVDD may be supplied to the first node through the fourth control transistor to turn off the fifth control transistor and turn on the sixth control transistor. When the OLED display is driven at a low frequency, the first control transistor and the second control transistor are turned on in response to the first low-frequency control signal, and the third control transistor and the fourth control transistor are turned off in response to the second low-frequency control signal. It can be. In this case, the data signal DATA may be supplied to the first node through the first control transistor. When the data signal DATA has a voltage level that turns off the fifth control transistor and turns on the sixth control transistor, the low power supply voltage (eg, ELVSS) is applied through the sixth control transistor to the organic light emitting diode EL. ) can be supplied to the anode electrode of When the data signal DATA has a voltage level that turns on the fifth control transistor and turns off the sixth control transistor, a compensation voltage may be supplied to the anode electrode of the organic light emitting diode EL through the fifth control transistor. there is. Accordingly, the driving current supplied to the organic light emitting diode EL may be compensated for during low-frequency driving.

Meanwhile, the second switching circuit 240 may further include a seventh control transistor and an eighth control transistor that reduce the voltage level of the data signal DATA. The seventh control transistor and the eighth control transistor may be connected between the first control transistor and the first node. Each of the seventh control transistor and the eighth control transistor may operate as a diode with the first electrode and the gate electrode connected thereto. When the first control transistor is turned on, the voltage level of the data signal DATA supplied to the first node through the first control transistor may be reduced by the seventh and eighth control transistors. Therefore, the fifth control transistor and the sixth control transistor can be stably driven (turned on or turned off).

As described above, the pixel PX of the organic light emitting diode display of FIG. 1 includes the low frequency compensation circuit 200 and supplies a compensation voltage to the anode electrode of the organic light emitting diode EL when the organic light emitting display device is driven at a low frequency. Accordingly, it is possible to prevent image quality defects caused by leakage current of the storage capacitor during low-frequency driving.

FIG. 2 is a circuit diagram illustrating an example of a pixel of FIG. 1 .

Referring to FIG. 2 , the pixel PX of the organic light emitting display device may include an organic light emitting diode EL, a driving circuit 100 and a low frequency compensation circuit 200 .

The driving circuit 100 may generate a driving current corresponding to the data signal DATA and supply the driving current to the organic light emitting diode EL. The driving circuit 100 includes a first switching transistor TS1, a second switching transistor TS2, a driving transistor TD, a storage capacitor CST, a first light emission control transistor TE1, and a second light emission control transistor TE2. ), a first initialization transistor TI1 and a second initialization transistor TI2.

The first switching transistor TS1 and the second switching transistor TS2 may transmit the data signal DATA supplied through the data supply line to the storage capacitor CST in response to the scan signal SCAN[n]. The first switching transistor TS1 may include a gate electrode connected to the n-th scan supply line, a first electrode connected to the data supply line, and a second electrode connected to the first electrode of the driving transistor TD. The second switching transistor TS2 includes a gate electrode connected to the n-th scan supply line, a first electrode connected to the second electrode of the storage capacitor CST, and a second electrode connected to the second electrode of the driving transistor TD. can include The first switching transistor TS1 and the second switching transistor TS2 may be turned on in response to the scan signal SCAN[n] supplied through the nth scan supply line. When the first switching transistor TS1 and the second switching transistor TS2 are turned on, the data signal DATA supplied to the first electrode of the first switching transistor TS1 passes through the second switching transistor TS2 to the storage capacitor. (CST).

The storage capacitor CST may be connected between the high power supply voltage line and the gate electrode of the driving transistor TD to store the data signal DATA. The storage capacitor CST may store the data signal DATA supplied through the first switching transistor TS1 and the second switching transistor TS2 during a scan period in which the scan signal SCAN[n] is supplied. The storage capacitor CST may include a first electrode connected to the high power voltage line and a second electrode connected to the first electrode of the second switching transistor TS2. The data signal DATA stored in the storage capacitor CST may be supplied to the gate electrode of the driving transistor TD.

The driving transistor TD may generate a driving current flowing through the organic light emitting diode EL in response to the data signal DATA. The driving transistor TD includes a gate electrode connected to the second electrode of the storage capacitor CST, a first electrode connected to the second electrode of the first light emission control transistor TE1, and a first electrode of the second light emission control transistor TE2. A second electrode connected to the first electrode may be included. The driving transistor TD may generate a driving current corresponding to the data signal DATA supplied from the storage capacitor CST.

The first light emission control transistor TE1 and the second light emission control transistor TE2 may be connected between the driving transistor TD and the organic light emitting diode EL. The first light emission control transistor TE1 and the second light emission control transistor TE2 may control whether the organic light emitting diode EL emits light. The first light emission control transistor TE1 may include a gate electrode connected to the nth light emission control line, a first electrode connected to the second power supply line, and a second electrode connected to the first electrode of the driving transistor TD. can The second emission control transistor TE2 includes a gate electrode connected to the nth emission control line, a first electrode connected to the second electrode of the driving transistor TD, and a second electrode connected to the anode electrode of the organic light emitting diode EL. electrodes may be included. The first light emission control transistor TE1 and the second light emission control transistor TE2 may be turned on in response to the light emission control signal EM[n] supplied through the nth light emission control line. When the first light emission control transistor TE1 and the second light emission control transistor TE2 are turned on, the driving current generated by the driving transistor TD may flow to the organic light emitting diode EL. Accordingly, the organic light emitting diode EL may emit light while the first light emitting control transistor TE1 and the second light emitting control transistor TE2 are turned on.

The first initialization transistor TI1 may initialize the gate electrode of the driving transistor TD. The first initialization transistor TI1 includes a gate electrode connected to the (n−1)th scan supply line, a first electrode connected to the gate electrode of the driving transistor TD, and a second electrode connected to the initialization voltage supply line. can do. The first initialization transistor TI1 may be turned on in response to the scan signal SCAN[n−1] supplied through the (n−1)th scan supply wire. When the first initialization transistor TI1 is turned on, the initialization voltage VINT may be supplied to the gate electrode of the driving transistor TD through the initialization voltage supply line. Accordingly, the same driving current may be generated in all pixels PX regardless of the threshold voltage deviation of the driving transistor TD. The second initialization transistor TI2 may initialize the anode electrode of the organic light emitting diode EL. The second initialization transistor TI2 includes a gate electrode connected to the (n−1)th scan supply line, a first electrode connected to the anode electrode of the organic light emitting diode EL, and a second electrode connected to the initialization voltage supply line. can include The second initialization transistor TI2 may be turned on in response to the scan signal SCAN[n−1] supplied through the (n−1)th scan supply line. When the second initialization transistor TI2 is turned on, the initialization voltage VINT may be supplied to the anode electrode of the organic light emitting diode EL through the initialization voltage supply line. Accordingly, the anode electrodes of the organic light emitting diodes EL of all pixels PX may have the same voltage level.

2 shows a first switching transistor TS1, a second switching transistor TS2, a driving transistor TD, a first light emission control transistor TE1, a second light emission control transistor TE2, and a first initialization transistor TI1. And although the driving circuit 100 is shown in which the second initialization transistor TI2 is implemented with P-channel Metal Oxide Semiconductor (PMOS) transistors, the first switching transistor TS1 and the second switching transistor TS2 , the driving transistor TD, the first emission control transistor TE1, the second emission control transistor TE2, the first initialization transistor TI1, and the second initialization transistor TI2 are not limited thereto. For example, the first switching transistor TS1, the second switching transistor TS2, the driving transistor TD, the first light emission control transistor TE1, the second light emission control transistor TE2, and the first initialization transistor TI1. ) and the second initialization transistor TI2 may be implemented as NMOS transistors.

The low frequency compensation circuit 200 may supply a compensation voltage Vc having a predetermined voltage level to the anode electrode of the organic light emitting diode EL to compensate for the driving current when the organic light emitting display device is driven at a low frequency. The low frequency compensation circuit 200 is a first switching circuit for supplying the data signal DATA to the first node N1 in response to the first low frequency control signal LCS1, and a high voltage in response to the second low frequency control signal LCS2. A second switching circuit for supplying the source voltage ELVDD to the first node N1 and the compensation voltage Vc in response to the data signal DATA or the high power supply voltage ELVDD supplied to the first node N1. A third switching circuit supplying an anode electrode of the organic light emitting diode (EL) may be included. In the low frequency compensation circuit 200 of FIG. 2 , the first switching circuit includes a first control transistor TC1, the second switching circuit includes a second control transistor TC2, and the third switching circuit includes a first control transistor TC1. 3 control transistors TC3 may be included.

The first control transistor TC1 may supply the data signal DATA to the first node N1 in response to the first low frequency control signal LCS1. The first control transistor TC1 includes a gate electrode connected to the first low-frequency control signal supply line, a first electrode connected to the second electrode of the storage capacitor CST, and a second electrode connected to the first node N1. can include When the first control transistor TC1 is turned on, the data signal DATA stored in the storage capacitor CST may be supplied to the first node N1 through the first control transistor TC1.

The second control transistor TC2 may supply the high power supply voltage ELVDD to the first node N1 in response to the second low frequency control signal LCS2. The second control transistor TC2 may include a gate electrode connected to the second low-frequency control signal supply line, a first electrode connected to the first node N1, and a second electrode connected to the high power supply voltage line. When the second control transistor TC2 is turned on, the high power supply voltage ELVDD may be supplied to the first node N1 through the second control transistor TC2.

The third control transistor TC3 may supply the compensation voltage Vc to the anode electrode of the organic light emitting diode EL in response to the data signal DATA or the high power supply voltage ELVDD supplied to the first node N1. there is. The third control transistor TC3 includes a gate electrode connected to the first node N1, a first electrode connected to the anode electrode of the organic light emitting diode EL, and a compensation voltage line supplying a preset compensation voltage Vc. A second electrode connected thereto may be included. When the third control transistor TC3 is turned on, the compensation voltage Vc may be supplied to the anode electrode of the organic light emitting diode EL through the third control transistor TC3.

Although FIG. 2 shows the low frequency compensation circuit 200 in which the first to third control transistors are implemented as PMOS transistors, the first to third control transistors TC1 , TC2 , and TC3 are not limited thereto. For example, the first to third control transistors TC1 , TC2 , and TC3 may be implemented as NMOS transistors.

3 to 5 are circuit diagrams for explaining the operation of the pixel of FIG. 2 .

Referring to FIG. 3 , a first low frequency control signal LCS1 having a high level and a second low frequency control signal LCS2 having a low level may be supplied to the low frequency compensation circuit 200 during normal driving of the OLED display. there is. The first control transistor TC1 may be turned off in response to the first low-frequency control signal LCS1 having a high level. The second control transistor TC2 may be turned on in response to the second low frequency control signal LCS2 having a low level. When the second control transistor TC2 is turned on, the high power voltage ELVDD may be supplied to the first node N1 through the high power voltage wire connected to the second electrode of the second control transistor TC2. The third control transistor TC3 may be turned off in response to the high power supply voltage ELVDD (ie, the high level voltage) applied to the first node N1. Accordingly, voltage may not be supplied to the anode electrode of the organic light emitting diode EL.

Referring to FIG. 4 , a first low-frequency control signal LCS1 having a low level and a second low-frequency control signal LCS2 having a high level may be supplied to the low-frequency compensation circuit 200 when the OLED display is driven at a low frequency. there is. The first control transistor TC1 may be turned on in response to the first low-frequency control signal LCS1 having a low level. When the first control transistor TC1 is turned on, the data signal DATA of the storage capacitor CST may be supplied to the first node N1 through the first control transistor TC1. When the data signal DATA has a low level (eg, a voltage level corresponding to white), the third control transistor TC3 may be turned on by the voltage of the first node N1. When the third control transistor TC3 is turned on, the compensation voltage Vc supplied through the compensation voltage line connected to the second electrode of the third control transistor TC3 is applied to the organic light emitting diode through the third control transistor TC3. It can be supplied to the anode electrode of (EL). Accordingly, the driving current changed by the leakage current of the storage capacitor CST can be compensated for. Meanwhile, the second control transistor TC2 may be turned off in response to the second low frequency control signal LCS2 having a high level.

Referring to FIG. 5 , when the OLED display is driven at a low frequency, a first low frequency control signal LCS1 having a low level and a second low frequency control signal LCS2 having a high level may be supplied to the low frequency compensation circuit 200 . there is. The first control transistor TC1 may be turned on in response to the first low-frequency control signal LCS1 having a low level. When the first control transistor TC1 is turned on, the data signal DATA of the storage capacitor CST may be supplied to the first node N1 through the first control transistor TC1. When the data signal DATA has a high level (eg, a voltage level corresponding to black), the driving transistor TD of the driving circuit 100 is turned off and does not generate a driving current. The compensation voltage Vc does not need to be supplied to the light emitting diode EL. When the data signal DATA has a high level (eg, a voltage level corresponding to black), the third control transistor TC3 may be turned off by the voltage of the first node N1. . Accordingly, voltage may not be supplied to the anode electrode of the organic light emitting diode EL. Meanwhile, the second control transistor TC2 may be turned off in response to the second low frequency control signal LCS2 having a high level.

As described above, by supplying the compensation voltage Vc to the anode electrode of the organic light emitting diode (EL) when the organic light emitting display device is driven at a low frequency, the image quality defect caused by the leakage current of the storage capacitor (CST) during the low frequency driving is reduced. can be prevented

6 is a circuit diagram illustrating another example of the pixel PX of FIG. 1 .

Referring to FIG. 6 , the pixel PX of the organic light emitting display device may include an organic light emitting diode EL, a driving circuit 100 and a low frequency compensation circuit 200 .

The driving circuit 100 may generate a driving current corresponding to the data signal DATA and supply the driving current to the organic light emitting diode EL. The driving circuit 100 may include a switching transistor TS, a driving transistor TD, and a storage capacitor CST. The switching transistor TS may transfer the data signal DATA supplied through the data supply line to the storage capacitor CST in response to the scan signal SCAN. The switching transistor TS may include a gate electrode connected to the scan supply line, a first electrode connected to the data supply line, and a second electrode connected to the second electrode of the storage capacitor CST. When the switching transistor TS is turned on in response to the scan signal SCAN, the data signal DATA supplied to the first electrode of the switching transistor TS may be supplied to the storage capacitor CST. The storage capacitor CST may be connected between the high power supply voltage line and the first electrode of the third control transistor TC3 of the low frequency compensation circuit 200 to store the data signal DATA. The storage capacitor CST may store the data signal DATA supplied through the switching transistor TS during a scan period in which the scan signal SCAN is supplied. The storage capacitor CST may include a first electrode connected to the high power supply voltage line and a second electrode connected to the first electrode of the third control transistor TC3. The data signal DATA stored in the storage capacitor CST may be supplied to the gate electrode of the driving transistor TD when the third control transistor TC3 is turned on.

The driving transistor TD may generate a driving current flowing through the organic light emitting diode EL in response to the data signal DATA. The driving transistor TD includes a gate electrode connected to the second electrode of the third control transistor TC3, a first electrode connected to the high power supply voltage line, and a second electrode connected to the anode electrode of the organic light emitting diode EL. can include The driving transistor TD may generate a driving current corresponding to the data signal DATA supplied from the storage capacitor CST.

Although FIG. 6 illustrates the driving circuit 100 in which the switching transistor TS and the driving transistor TD are implemented as NMOS transistors, the switching transistor TS and the driving transistor TD are not limited thereto. For example, the switching transistor TS and the driving transistor TD may be implemented as PMOS transistors.

The low frequency compensation circuit 200 may supply a compensation voltage Vc having a predetermined voltage level to the anode electrode of the organic light emitting diode EL to compensate for the driving current when the organic light emitting display device is driven at a low frequency. The low frequency compensation circuit 200 is a first switching circuit for supplying the data signal DATA to the first node N1 in response to the first low frequency control signal LCS1, and a high voltage in response to the second low frequency control signal LCS2. The switching circuit for supplying the source voltage to the first node N1 and the compensation voltage Vc in response to the data signal DATA or the high power supply voltage ELVDD supplied to the first node N1, the organic light emitting diode EL ) It may include a third switching circuit for supplying to the anode electrode. In the low frequency compensation circuit 200 of FIG. 6 , the first switching circuit includes a first control transistor TC1 and a second control transistor TC2, and the second switching circuit includes a third control transistor TC3 and a second control transistor TC3. Four control transistors TC4 are included, and the third switching circuit may include a fifth control transistor TC5 and a sixth control transistor TC6.

The first control transistor TC1 and the second control transistor TC2 may be turned on or off in response to the first low frequency control signal LCS1. The first control transistor TC1 includes a gate electrode connected to the first low-frequency control signal supply line, a first electrode connected to the second electrode of the storage capacitor CST, and a second electrode connected to the first node N1. can include When the first control transistor TC1 is turned on, the data signal DATA stored in the storage capacitor CST may be supplied to the first node N1 through the first control transistor TC1. The second control transistor TC2 includes a gate electrode connected to the first low-frequency control signal supply line, a first electrode connected to the second node N2, and a second electrode connected to the anode electrode of the organic light emitting diode EL. can include When the second control transistor TC2 is turned on, the voltage of the second node N2 may be supplied to the anode electrode of the organic light emitting diode EL through the second control transistor TC2.

The third control transistor TC3 and the fourth control transistor TC4 may be turned on or off in response to the second low frequency control signal LCS2. The third control transistor TC3 has a gate electrode connected to the second low-frequency control signal supply line, a first electrode connected to the second electrode of the storage capacitor CST, and a second electrode connected to the gate electrode of the driving transistor TD. electrodes may be included. When the third control transistor TC3 is turned on, the data signal DATA stored in the storage capacitor CST may be supplied to the gate electrode of the driving transistor TD through the third control transistor TC3. The fourth control transistor TC4 may include a gate electrode connected to the second low-frequency control signal supply line, a first electrode connected to the high power supply voltage line, and a second electrode connected to the first node N1. When the fourth control transistor TC4 is turned on, the high power supply voltage ELVDD may be supplied to the first node N1 through the fourth control transistor TC4.

The fifth control transistor TC5 and the sixth control transistor TC6 may be turned on or off in response to the data signal DATA or the high power supply voltage ELVDD. The fifth control transistor TC5 may include a gate electrode connected to the first node N1, a first electrode connected to the high power voltage line, and a second electrode connected to the second node N2. When the fifth control transistor TC5 is turned on, the high power supply voltage ELVDD may be supplied to the anode electrode of the organic light emitting diode EL through the fifth control transistor TC5. The sixth control transistor TC6 may include a gate electrode connected to the first node N1, a first electrode connected to the second node N2, and a second electrode connected to the low power voltage line. When the sixth control transistor TC6 is turned on, a low power supply voltage (eg, 0V) may be supplied to the anode electrode of the organic light emitting diode EL through the sixth control transistor TC6. The fifth control transistor TC5 and the sixth control transistor TC6 may be turned on in response to voltages of the first node N1 having different voltage levels. In one embodiment, the fifth control transistor TC5 may be implemented as an NMOS transistor, and the sixth control transistor TC6 may be implemented as a PMOS transistor. In another embodiment, the fifth control transistor TC5 may be implemented as a PMOS transistor, and the sixth control transistor TC6 may be implemented as an NMOS transistor.

6 shows a low frequency compensation circuit 200 in which the first to fifth control transistors TC1, TC2, TC3, TC4, and TC5 are implemented as PMOS transistors, and the sixth control transistor TC6 is implemented as an NMOS transistor. Although shown, the first to sixth control transistors TC1, TC2, TC3, TC4, TC5, and TC6 are not limited thereto. For example, the first to fifth control transistors TC1 , TC2 , TC3 , TC4 , and TC5 may be implemented as NMOS transistors, and the sixth control transistor TC6 may be implemented as a PMOS transistor.

7 to 9 are circuit diagrams for explaining the operation of the pixel of FIG. 6 .

Referring to FIG. 7 , during normal driving of the OLED display, a first low-frequency control signal LCS1 having a high level and a second low-frequency control signal LCS2 having a low level may be supplied. The first control transistor TC1 and the second control transistor TC2 may be turned off in response to the first low-frequency control signal LCS1 having a high level. The third control transistor TC3 and the fourth control transistor TC4 may be turned on in response to the second low-frequency control signal LCS2 having a low level. When the third control transistor TC3 is turned on, the data signal DATA stored in the storage capacitor CST may be supplied to the gate electrode of the driving transistor TD through the third control transistor TC3. When the fourth control transistor TC4 is turned on, the high power voltage ELVDD may be supplied to the first node N1 through the high power voltage wire connected to the first electrode of the fourth control transistor TC4. The fifth control transistor TC5 may be turned on in response to the high power supply voltage ELVDD (ie, the high level voltage) applied to the first node N1. When the fifth control transistor TC5 is turned on, the high power voltage ELVDD may be supplied to the second node N2 through the high power voltage wire connected to the first electrode of the fifth control transistor TC5. At this time, the voltage of the second node N2 may not be supplied to the anode electrode of the organic light emitting diode EL because the second control transistor TC2 is turned off. The sixth control transistor TC6 may be turned off in response to the high power supply voltage ELVDD (ie, a high level voltage) applied to the first node N1. Accordingly, voltage may not be supplied to the anode electrode of the organic light emitting diode EL.

Referring to FIG. 8 , when the OLED display is driven at a low frequency, a first low frequency control signal LCS1 having a low level and a second low frequency control signal LCS2 having a high level may be supplied to the low frequency compensation circuit 200 . there is. The first control transistor TC1 and the second control transistor TC2 may be turned on in response to the first low-frequency control signal LCS1 having a low level. When the first control transistor TC1 is turned on, the data signal DATA of the storage capacitor CST may be supplied to the first node N1 through the first control transistor TC1. When the data signal DATA has a low level (eg, a voltage level corresponding to white), the fifth control transistor TC5 is turned on and the sixth control transistor TC6 is turned off. there is. When the fifth control transistor TC5 is turned on, the high power voltage ELVDD may be supplied to the second node N2 through the high power voltage wire connected to the first electrode of the fifth control transistor TC5. A voltage of the second node N2 may be supplied to the anode electrode of the organic light emitting diode EL through the second control transistor TC2. That is, the high power supply voltage ELVDD supplied to the second node N2 may be supplied to the anode electrode of the organic light emitting diode EL as a compensation voltage. Accordingly, the driving current changed by the leakage current of the storage capacitor CST can be compensated for. Meanwhile, the third control transistor TC3 and the fourth control transistor TC4 may be turned off in response to the second low frequency control signal LCS2 having a high level.

Referring to FIG. 9 , a first low-frequency control signal LCS1 having a low level and a second low-frequency control signal LCS2 having a high level may be supplied to the low-frequency compensation circuit 200 when the OLED display is driven at a low frequency. there is. The first control transistor TC1 and the second control transistor TC2 may be turned on in response to the first low-frequency control signal LCS1 having a low level. When the first control transistor TC1 is turned on, the data signal DATA of the storage capacitor CST may be supplied to the first node N1 through the first control transistor TC1. When the data signal DATA has a high level (eg, a voltage level corresponding to black), the driving transistor TD of the driving circuit 100 is turned off and does not generate a driving current. A compensation voltage does not need to be supplied to the light emitting diode EL. When the data signal DATA has a high level (eg, a voltage level corresponding to black), the fifth control transistor TC5 is turned off and the sixth control transistor TC6 is turned on. there is. When the sixth control transistor TC6 is turned on, the low power voltage may be supplied to the second node N2 through the low power voltage wire connected to the second electrode of the sixth control transistor TC6. A voltage of the second node N2 may be supplied to the anode electrode of the organic light emitting diode EL through the second transistor. Meanwhile, the third control transistor TC3 and the fourth control transistor TC4 may be turned off in response to the second low frequency control signal LCS2 having a high level.

As described above, the leakage current of the storage capacitor CST during low-frequency driving by supplying the compensation voltage (ie, the high power supply voltage ELVDD) to the anode electrode of the organic light-emitting diode EL during low-frequency driving of the organic light-emitting display device. Defective image quality caused by this can be prevented.

10 is a circuit diagram illustrating another example of the pixel of FIG. 1 .

Referring to FIG. 10 , the pixel PX of FIG. 10 is the pixel PX of FIG. 6 except that the low frequency compensation circuit 200 includes the seventh control transistor TC7 and the eighth control transistor TC8. ) and may have substantially the same or similar configuration. Therefore, in describing the pixel PX of FIG. 10 , description of components substantially the same as or similar to those of the pixel PX of FIG. 6 will be omitted.

Referring to FIG. 10 , the low frequency compensation circuit 200 of the pixel PX may further include a seventh control transistor TC7 and an eighth control transistor TC8. The seventh control transistor TC7 and the eighth control transistor TC8 may be connected between the first control transistor TC1 and the first node N1. Each of the seventh control transistor TC7 and the eighth control transistor TC8 may operate as a diode with a first electrode and a gate electrode connected thereto. When the first control transistor TC1 is turned on, the voltage level of the data signal DATA supplied to the first node N1 through the first control transistor TC1 is increased by the seventh control transistor TC7 and the eighth control transistor TC7. It can be reduced by transistor TC8. Therefore, the fifth control transistor TC5 and the sixth control transistor TC6 can be stably driven (turned on or turned off).

11 is a block diagram illustrating an organic light emitting display device according to example embodiments.

Referring to FIG. 11 , the organic light emitting diode display 300 may include a display panel 310 , a data driver 320 , a scan driver 330 , an emission controller 340 and a timing controller 350 .

The display panel 310 may include a plurality of pixels. A plurality of data lines, a plurality of scan lines, and a plurality of emission control lines may be formed in the display panel 310 . A plurality of pixels may be formed in an area where data lines and scan lines intersect.

Each pixel may include an organic light emitting diode, a driving circuit, and a low frequency compensation circuit. The organic light emitting diode may emit light according to a driving current flowing through an anode electrode. An anode electrode of the organic light emitting diode may be connected to a driving circuit and a low frequency compensation circuit, and a cathode electrode of the organic light emitting diode may be connected to a low power supply voltage line supplying a low power supply voltage. The driving circuit may generate driving current generated in the data signal DATA and supply the driving current to the organic light emitting diode. The driving circuit may be connected to a scan supply wire, a data supply wire, and a high power supply voltage wire. The driving circuit may receive the data signal DATA from the data supply line in response to the scan signal SCAN supplied through the scan supply line, and generate a driving current corresponding to the data signal DATA. The low frequency compensation circuit may supply a compensation voltage having a predetermined voltage level to the anode electrode of the organic light emitting diode to compensate for the driving current when the organic light emitting diode display 300 is driven at a low frequency. The low frequency compensation circuit may be coupled with the driving circuit and the high power supply voltage wiring. The low frequency compensation circuit may include a first switching circuit, a second switching circuit, and a third switching circuit. The first switching circuit may supply the data signal DATA to the first node in response to the first low frequency control signal. The second switching circuit may supply a high power supply voltage (eg, ELVDD) to the first node in response to the second low frequency control signal. The third switching circuit may supply a compensation voltage to the anode electrode of the organic light emitting diode in response to the data signal DATA or the high power supply voltage supplied to the first node. In this case, the first low frequency control signal may be activated when the organic light emitting display device 300 is driven at a low frequency, and the second low frequency control signal may be activated when the organic light emitting display device 300 is normally driven.

In one embodiment, the first switching circuit includes a first control transistor turned on or off in response to a first low frequency control signal, and the second switching circuit includes a first control transistor turned on or off in response to a second low frequency control signal. 2 control transistors, and the third switching circuit may include a third control transistor turned on or off in response to a data signal DATA supplied to the first node or a high power supply voltage. When the OLED display 300 is normally driven, the first control transistor may be turned off in response to the first low-frequency control signal, and the second control transistor may be turned on in response to the second low-frequency control signal. Also, when the organic light emitting diode display 300 is driven at a low frequency, the first control transistor may be turned on and the second control transistor may be turned off in response to the first low frequency control signal.

In another embodiment, the first switching circuit includes a first control transistor and a second control transistor that are turned on or off in response to the first low frequency control signal, and the second switching circuit is turned on in response to the second low frequency control signal. or a third control transistor and a fourth control transistor turned off, and the third switching circuit includes a fifth control transistor and a sixth control transistor turned on or off in response to a data signal DATA or a high power supply voltage. can do. In one embodiment, when the fifth control transistor is an NMOS transistor, the sixth control transistor may be a PMOS transistor. In another embodiment, when the fifth control transistor is a PMOS transistor, the sixth control transistor may be an NMOS transistor. When the OLED display 300 is normally driven, the first control transistor and the second control transistor are turned off in response to the first low-frequency control signal, and the third control transistor and the fourth control transistor are turned off in response to the second low-frequency control signal. A transistor can be turned on. When the OLED display 300 is driven at a low frequency, the first control transistor and the second control transistor are turned on in response to the first low-frequency control signal, and the third control transistor and the fourth control transistor are turned on in response to the second low-frequency control signal. can be turned off. Meanwhile, the second switching circuit may further include a seventh control transistor and an eighth control transistor that reduce the voltage level of the data signal DATA.

The scan driver 330 may supply scan signals SCAN to pixels through scan supply wires. The data driver 320 may supply the data signal DATA to the pixels through the data supply wiring according to the scan signal SCAN. The emission controller 340 may supply an emission control signal EM for controlling whether the organic light emitting diode emits light to the pixels through an emission control line. The timing controller 350 may generate control signals CTL1 and CTL2 that control the scan driver 330 , the data driver 320 , and the emission controller 340 .

As described above, the organic light emitting display device 300 of FIG. 11 includes a low frequency compensation circuit in each pixel and supplies a compensation voltage to the anode electrode of the organic light emitting diode when the organic light emitting display device 300 is driven at a low frequency. , it is possible to prevent image quality defects that occur during low-frequency driving.

FIG. 12 is a block diagram illustrating an electronic device including the organic light emitting display device of FIG. 11 , and FIG. 13 is a diagram illustrating an example in which the electronic device of FIG. 12 is implemented as a smartphone.

12 and 11, the electronic device 400 includes a processor 410, a memory device 420, a storage device 430, an input/output device 440, a power supply 450, and a display device 460. can include In this case, the display device 460 may correspond to the organic light emitting display device 300 of FIG. 11 . Furthermore, the electronic device 400 may further include several ports capable of communicating with a video card, a sound card, a memory card, a USB device, or the like or communicating with other systems. Meanwhile, as shown in FIG. 13 , the electronic device 400 may be implemented as a smart phone 500, but the electronic device 400 is not limited thereto.

Processor 410 may perform certain calculations or tasks. In one embodiment, the processor 410 may be a microprocessor, central processing unit (CPU), or the like. The processor 410 may be connected to other components through an address bus, a control bus, and a data bus. Additionally, the processor 410 may be coupled to an expansion bus such as a Peripheral Component Interconnect (PCI) bus. The memory device 420 may store data necessary for the operation of the electronic device 400 . For example, the memory device 420 may include EPROM, EEPROM, flash memory, phase change random access memory (PRAM), resistance random access memory (RRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), and the like. It may include a non-volatile memory device and/or a volatile memory device such as dynamic random access memory (DRAM), static random access memory (SRAM), and mobile DRAM. The storage device 430 may include a solid state drive (SSD), a hard disk drive (HDD), a CD-ROM, and the like.

The input/output device 440 may include an input means such as a keyboard, a keypad, a touch pad, a touch screen, and a mouse, and an output means such as a speaker and a printer. The display device 460 may be included in the input/output device 440 . The power supply 450 may supply power necessary for the operation of the electronic device 400 . The display device 460 may be connected to other components through the buses or other communication links. As described above, the display device 460 may include a display panel, a data driver, a scan driver, an emission controller, and a timing controller. The display panel may include a plurality of pixels. Each pixel may include an organic light emitting diode, a driving circuit, and a low frequency compensation circuit. The organic light emitting diode may emit light according to a driving current flowing through an anode electrode. The driving circuit may generate a driving current generated in the data signal and supply it to the organic light emitting diode. The low frequency compensation circuit may supply a compensation voltage having a predetermined voltage level to an anode electrode of the organic light emitting diode to compensate for a driving current when the organic light emitting diode display is driven at a low frequency. The low frequency compensation circuit may include a first switching circuit, a second switching circuit, and a third switching circuit. The first switching circuit may supply a data signal to the first node in response to the first low frequency control signal. The second switching circuit may supply a high power supply voltage (eg, ELVDD) to the first node in response to the second low frequency control signal. The third switching circuit may supply a compensation voltage to the anode electrode of the organic light emitting diode in response to a data signal or a high power supply voltage supplied to the first node. The scan driver may supply scan signals to pixels through scan wires. The data driver may supply data signals to the pixels through the data lines according to the scan signal. The light emitting controller may supply a light emitting control signal for controlling whether or not the organic light emitting diode emits light to the pixels through the light emitting control line. The timing controller may generate control signals for controlling the scan driver, the data driver, and the emission controller.

As described above, the electronic device 400 of FIG. 12 forms a low frequency compensation circuit in each pixel included in the display panel and supplies a compensation voltage to the anode electrode of the organic light emitting diode when the display device 460 is driven at a low frequency. , it is possible to prevent image quality defects that occur during low-frequency driving.

The present invention can be applied to all electronic devices equipped with a display device. For example, the present invention can be applied to televisions, computer monitors, notebooks, digital cameras, mobile phones, smart phones, smart pads, tablet PCs, PDAs, PMPs, MP3 players, navigations, video phones, and the like.

Although the above has been described with reference to exemplary embodiments of the present invention, those skilled in the art can make various modifications to the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. It will be understood that it can be modified and changed accordingly.

100: driving circuit 200: low frequency compensation circuit
300: organic light emitting display device 400: electronic device
500: smartphone

Claims (20)

organic light emitting diodes;
a driving circuit generating a driving current corresponding to a data signal and supplying the driving current to the organic light emitting diode; and
A pixel of an organic light emitting diode display comprising: a low frequency compensation circuit supplying a compensation voltage having a predetermined voltage level to an anode electrode of the organic light emitting diode to compensate for the driving current when the organic light emitting diode is driven at a low frequency. The method of claim 1, wherein the low frequency compensation circuit
a first switching circuit supplying the data signal to a first node in response to a first low frequency control signal;
a second switching circuit supplying a high power supply voltage to the first node in response to a second low frequency control signal; and
and a third switching circuit supplying the compensation voltage to the anode electrode of the organic light emitting diode in response to the data signal or the high power supply voltage supplied to the first node. . 3. The method of claim 2, wherein the first switching circuit comprises a first control transistor turned on or off in response to the first low-frequency control signal,
The second switching circuit includes a second control transistor turned on or off in response to the second low-frequency control signal,
The third switching circuit includes a third control transistor turned on or off in response to the data signal supplied to the first node or the high power supply voltage. The pixel of claim 3 , wherein the first control transistor is turned off and the second control transistor is turned on during normal driving. The pixel of claim 3 , wherein the first control transistor is turned on and the second control transistor is turned off during the low frequency driving. 3. The method of claim 2, wherein the first switching circuit includes a first control transistor and a second control transistor turned on or off in response to the first low-frequency control signal,
The second switching circuit includes a third control transistor and a fourth control transistor turned on or off in response to the second low-frequency control signal,
The third switching circuit includes a fifth control transistor and a sixth control transistor turned on or off in response to the data signal or the high power supply voltage. The pixel of claim 6 , wherein the first control transistor and the second control transistor are turned off and the third control transistor and the fourth control transistor are turned on during normal driving. The pixel of claim 6 , wherein the first control transistor and the second control transistor are turned on, and the third control transistor and the fourth control transistor are turned off during the low frequency driving. 7. The method of claim 6 , wherein the fifth control transistor is an N-channel Metal Oxide Semiconductor (NMOS) transistor, and the sixth control transistor is a P-channel Metal Oxide Semiconductor (PMOS) transistor. A pixel of an organic light emitting display device that 7. The method of claim 6 , wherein the fifth control transistor is a P-channel Metal Oxide Semiconductor (PMOS) transistor, and the sixth control transistor is an N-channel Metal Oxide Semiconductor (NMOS) transistor. A pixel of an organic light emitting display device that 7 . The pixel of claim 6 , wherein the second switching circuit further comprises a seventh control transistor and an eighth control transistor configured to reduce a voltage level of the data signal. a display panel including a plurality of pixels;
a data driver supplying data signals to the pixels;
a scan driver supplying scan signals to the pixels;
a light emitting controller supplying light emitting control signals to the pixels; and
and a timing controller generating control signals for controlling operations of the data driver, the scan driver, and the light emitting controller, each of the pixels
organic light emitting diodes;
a driving circuit generating a driving current corresponding to the data signal and supplying the driving current to the organic light emitting diode; and
and a low-frequency compensation circuit supplying a compensation voltage having a predetermined voltage level to an anode electrode of the organic light-emitting diode to compensate for the driving current during low-frequency driving. 13. The method of claim 12, wherein the low frequency compensation circuit
a first switching circuit supplying the data signal to a first node in response to a first low frequency control signal;
a second switching circuit supplying a high power supply voltage to the first node in response to a second low frequency control signal; and
and a third switching circuit supplying the compensation voltage to the anode electrode of the organic light emitting diode in response to the data signal or the high power supply voltage supplied to the first node. 14. The method of claim 13, wherein the first switching circuit comprises a first control transistor turned on or off in response to the first low-frequency control signal,
The second switching circuit includes a second control transistor turned on or off in response to the second low-frequency control signal,
The organic light emitting display device of claim 1 , wherein the third switching circuit includes a third control transistor turned on or off in response to the data signal supplied to the first node or the high power supply voltage. 15. The organic light emitting diode display as claimed in claim 14, wherein the first control transistor is turned off and the second control transistor is turned on during normal driving. 15 . The organic light emitting diode display of claim 14 , wherein the first control transistor is turned on and the second control transistor is turned off during the low frequency driving. 14. The method of claim 13, wherein the first switching circuit comprises a first control transistor and a second control transistor turned on or off in response to the first low-frequency control signal,
The second switching circuit includes third control transistors and fourth control transistors turned on or off in response to the second low-frequency control signal,
The third switching circuit includes a fifth control transistor and a sixth control transistor turned on or off in response to the data signal or the high power supply voltage. 18. The organic light emitting diode display as claimed in claim 17, wherein the first control transistor and the second control transistor are turned off, and the third control transistor and the fourth control transistor are turned on during normal driving. 18 . The organic light emitting diode display of claim 17 , wherein the first control transistor and the second control transistor are turned on, and the third control transistor and the fourth control transistor are turned off during the low frequency driving. 18 . The organic light emitting diode display of claim 17 , wherein the second switching circuit further comprises a seventh control transistor and an eighth control transistor configured to reduce a voltage level of the data signal.

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