Display device

1. A display device comprising:

a plurality of pixels commonly coupled to a first power line; and

a current sensor configured to provide a sensing value of a current flowing in the first power line,

wherein the pixels gradually decreases a luminance of a still image from a first time while the still image is being displayed,

wherein the first time is a time when a first period elapses from a time at which the display of the still image is started, and

wherein a length of the first period is changed depending on the sensing value at the time at which the display of the still image is started.

2. The display device of claim 1 , wherein the first period becomes shorter as the sensing value becomes smaller.

3. The display device of claim 2 , wherein the plurality of pixels maintain the luminance of the still image from a second time after the first time, and

wherein an interval between the time at which the display of the still image is started and the second time is set longer as the sensing value at the time at which the display of the still image is started becomes smaller.

4. The display device of claim 3 , wherein the pixels display a moving image at a third time after the second time, and gradually increase a luminance of the moving image from the third time.

5. The display device of claim 4 , wherein an increase rate of the luminance of the moving image is determined according to a difference between a sensing value at the third time and the sensing value at the time at which the display of the still image is started.

6. The display device of claim 1 , further comprising:

a gain provider configured to include a load comparator generating an enable signal when a difference between a load value of a first frame and a load value of a second frame is smaller than an enable threshold value, and configured to gradually decrease a gain value from the first time when the first period elapses, wherein the first period starts from a time at which the enable signal is generated to the first time,

wherein the pixels receive data voltages determined by the gain value and input grayscale values, and

wherein the gain provider determines a length of the first period according to a first load value based on the input grayscale values at the time at which the enable signal is generated.

7. The display device of claim 6 , wherein the gain provider determines the first period to become shorter as the first load value becomes smaller.

8. The display device of claim 7 , wherein the gain provider maintains the gain value from a second time after the first time.

9. The display device of claim 8 , wherein an interval between the time at which the enable signal is generated and the second time is set constant regardless of the first load value.

10. The display device of claim 8 , wherein an interval between the time at which the enable signal is generated and the second time is set longer as the first load value becomes smaller.

11. The display device of claim 8 , wherein the gain provider includes:

a first frame counter configured to provide a first count value of frames from the time at which the enable signal is generated; and

a set gain controller configured to determine the first period, based on the first load value and the first count value.

12. The display device of claim 11 , wherein the set gain controller includes a plurality of set gain lookup tables different from each other according to the first load value.

13. The display device of claim 12 , wherein the set gain controller provides a first gain ratio value corresponding to the first count value with reference to a set gain lookup table selected according to the first load value.

14. The display device of claim 13 , further comprising:

an initial gain provider configured to provide an initial gain value based on the sensing value,

wherein the gain provider further includes a gain converter configured to convert the initial gain value into the gain value according to the first gain ratio value.

15. The display device of claim 14 , wherein the initial gain provider provides the initial gain value such that the sensing value is smaller than a current limit value, and

wherein the first gain ratio value is equal to 1 or less than 1.

16. The display device of claim 15 , wherein the gain provider gradually increases the gain value from a third time after the second time.

17. The display device of claim 16 , wherein the gain provider determines an increase rate of the gain value according to a second load value based on the input grayscale values at the third time.

18. The display device of claim 17 , wherein the gain provider determines an increase rate of the gain value according to a difference between the second load value and the first load value.

19. The display device of claim 17 , wherein the load comparator generates a disable signal when a difference between a load value of a third frame and a load value of a fourth frame is greater than a disable threshold value, and

wherein the gain provider includes:

a second frame counter configured to provide a second count value of frames from a time at which the disable signal is generated; and

a reset gain controller configured to determine the increase rate based on the second load value and the second count value.

20. The display device of claim 19 , wherein the reset gain controller includes a plurality of reset gain lookup tables different from each other according to the second load value.

21. The display device of claim 20 , wherein the reset gain controller provides a second gain ratio value corresponding to the second count value with reference to a reset gain lookup table selected according to the second load value.

22. The display device of claim 21 , wherein the gain converter converts the initial gain value into the gain value according to the second gain ratio value, and

wherein the second gain ratio value is equal to 1 or less than 1.