Display device and driving method thereof

1 . A display device comprising:

a display panel comprising a plurality of pixels arranged thereon;

a data driver configured to apply a sensing data voltage to the plurality of pixels and sense a characteristic value as sensing data in response to the sensing data voltage; and

a timing controller configured to determine compensation data to compensate video data based on the sensing data and transmit the compensation data and a control signal to the data driver,

wherein the data driver is configured to apply a first sensing data voltage to the plurality of pixels in a normal sensing drive mode and a second sensing data voltage higher than the first sensing data voltage to the plurality of pixels in an overdriving sensing drive mode,

wherein the data driver is configured to sense, upon a sensing voltage is applied to the pixels during a tracking period, the sensing voltage during a sampling period, to apply the second sensing data voltage to the plurality of pixels during an initialization period in the overdriving sensing drive mode, and to apply the first sensing data voltage lower than the second sensing data voltage to the plurality of pixels during the sampling period.

2 . The display device of claim 1 , wherein the timing controller is configured to calculate one or more of a gain value or an offset value as part of the compensation data for compensating the video data based on the sensing data and to transmit the one or more of the gain value or the offset value to the data driver.

3 . The display device of claim 2 , wherein the data driver is configured to compensate the video data received from the timing controller based on the offset value.

4 . The display device of claim 2 , wherein the data driver comprises:

a receiver configured to receive the video data from the timing controller;

a shift register configured to output a sampling signal in response to the control signal;

a latch configured to latch and output the video data in response to the sampling signal;

a digital-to-analog converter configured to convert the video data output from the latch into an analog data voltage;

an output buffer configured to supply the analog data voltage from the digital-to-analog converter to the plurality of pixels through a data line; and

an offset compensator configured to convert the offset value received from the timing controller into an analog offset voltage and provide the analog offset voltage to the digital-to-analog converter.

5 . The display device of claim 4 , wherein the digital-to-analog converter comprises:

a resister string configured to divide between a first gamma reference voltage and a second gamma reference voltage and output a plurality of gamma gradation voltages; and

a switch unit configured to output at an output terminal a gamma gradation voltage, among the plurality of gamma gradation voltages, corresponding to the video data output from the latch, wherein the offset compensator is connected to the output terminal of the switch unit.

6 . The display device of claim 1 , wherein the control signal comprises a 2-bit data indicative of the normal sensing drive mode, the overdriving sensing drive mode, or a sensing pre-charge drive mode.

7 . The display device of claim 6 , wherein the control signal comprises a first offset value for compensating an offset of the video data in the overdriving sensing drive mode and a second offset value for compensating the offset of the video data in the sensing pre-charge drive mode.

8 . The display device of claim 1 , wherein the data driver is configured to apply a pre-charge data voltage lower than the first sensing data voltage to the plurality of pixels during a pre-charge period in the sensing pre-charge drive mode and to apply the first sensing data voltage to the plurality of pixels during the initialization period.

9 . A method for driving a display device including a display panel including a plurality of pixels arranged thereon, a data driver applying data voltage to the plurality of pixels, and a timing controller controlling the data driver, the method comprising:

applying a second sensing data voltage to the plurality of pixels during an initialization period;

charging the pixels with a sensing voltage during a tracking period;

applying a first sensing data voltage to the pixels and sensing a characteristic of the plurality of pixels as sensing data in response to applying the first sensing data voltage to the pixels during a sampling period; and

compensating video data to be applied to the plurality of pixels based on the sensing data,

wherein the data driver is configured to apply a first sensing data voltage to the plurality of pixels in a normal sensing drive mode and a second sensing data voltage to the plurality of pixels in an overdriving sensing drive mode,

wherein the data driver is further configured to sense, upon the sensing voltage is applied to the pixels during the tracking period, the sensing voltage during the sampling period, to apply the second sensing data voltage to the plurality of pixels during an initialization period in the overdriving sensing drive mode, and to apply the first sensing data voltage lower than the second sensing data voltage to the plurality of pixels during the sampling period.

10 . The method of claim 9 , wherein the compensating the video data comprises:

calculating, by the timing controller, a gain value and an offset value for compensating the video data based on the sensing data; and

compensating the video data based on the gain value; and

transmitting the gain value-compensated video data and the offset value to the data driver.

11 . The method of claim 10 , wherein the compensating the video data further comprises compensating, by the data driver, the gain value-compensated video data received from the timing controller based on the received offset value.

12 . A display device comprising:

a display panel including a plurality of pixels arranged thereon;

a data driver configured to apply a first sensing voltage to a pixel in a first sensing drive mode and a second sensing voltage higher than the first sensing voltage to the pixel in a second sensing drive mode, and sense a characteristic of the pixel in response to the first sensing voltage or the second sensing voltage being applied to the pixel,

wherein the data driver is configured to sense, upon a sensing voltage is applied to the pixels during a tracking period, the sensing voltage during a sampling period, to apply the second sensing data voltage to the plurality of pixels during an initialization period in the overdriving sensing drive mode, and to apply the first sensing data voltage lower than the second sensing data voltage to the plurality of pixels during the sampling period.

13 . The display device of claim 12 , comprising a timing controller configured to send a control signal to the data driver, the control signal indicating the first sensing drive mode or the second sensing drive mode.

14 . The display device of claim 13 , wherein the data driver is configured to apply a pre-charge voltage lower than the first sensing voltage to the pixel during a pre-charge period in a third sensing drive mode and to apply the first sensing data voltage to the pixel during an initialization period in the third sensing drive mode.

15 . The display device of claim 13 , wherein the timing controller is configured to determine compensation to video data based on the characteristic of the pixel.