Organic light emitting diode display device

1. A display device comprising:

a panel in which a plurality of pixels are disposed;

a power supplier configured to supply a current to the panel; and

a controller configured to:

receive information on the supplied current;

determine a cumulative current based on the received information;

set a current limit value such that the supplied current is equal to or less than the set current limit value; and

adjust the set current limit value to a first limit value or a second limit value based on the determined cumulative current, wherein the second limit value is less than the first limit value.

2. The display device according to claim 1 , wherein the controller is further configured to determine the cumulative current by summing respective differences between a present current supplied to the panel and a reference value for each set period of time.

3. The display device according to claim 2 , wherein the controller is further configured to determine the cumulative current at a certain instance of time T by summing the difference between a present current supplied to the panel and a reference value at the certain time T and the cumulative current at an immediately previous instance of time T−1.

4. The display device according to claim 2 , wherein the reference value is less than the second limit value.

5. The display device according to claim 1 , wherein the controller is further configured to:

set the current limit value to the second limit value when the cumulative current is equal to or greater than a decrease condition value, wherein the decrease condition value serves as a reference value for decreasing the current limit value; and

set the current limit value to the first limit value when the cumulative value is less than an increase condition value, wherein the increase condition value serves as a reference for increasing the current limit value.

6. The display device according to claim 5 , wherein the controller is configured to:

maintain the current limit value at the first limit value when the current limit value is set to the first limit value and the cumulative current is less than the decrease condition value; and

maintain the current limit value at the second limit value when the current limit value is set to the second limit value and the cumulative current is at the increase condition value or more.

7. The display device according to claim 1 , wherein the controller is configured to correct the cumulative current to a preset minimum value when the cumulative current is less than the preset minimum value.

8. The display device according to claim 1 , wherein the controller is configured to correct the cumulative current to a preset maximum value when the cumulative current is at the preset maximum value or more.

9. The display device according to claim 1 , wherein the controller is configured to:

adjust the current limit value when a temperature reduction function is set; and

fix the current limit value when the temperature reduction function is released.

10. The display device according to claim 9 , wherein the controller is configured to:

set the current limit value to the first limit value or the second limit value less than the first limit value when the temperature reduction function is set; and

fix the current limit value to one of the first limit value and the second limit value when the temperature reduction function is released.

11. The display device according to claim 9 , wherein the controller is configured to:

reset the cumulative current to zero and calculate the cumulative current when a setting command of the temperature reduction function is received in a state in which the temperature reduction function is released; and

set the current limit value to the first limit value or the second limit value based on the cumulative current.

12. The display device according to claim 1 , wherein the controller is further configured to gradually increase the current limit value according to a setting ratio or gradually decrease the current limit value according to the setting ratio when the current limit value is adjusted.

13. The display device according to claim 1 , wherein the controller is further configured to compare a present current supplied to the panel with a third limit value and set the current limit value to a first limit value or a second limit value less than a normal limit value,

wherein the controller is preferably configured to set the current limit value to the first limit value when the present current is less than the third limit value, and set the current limit value to the second limit value when the present current is the third limit value or more.

14. An operating method of a display device comprising a panel in which a plurality of pixels are disposed, the operating method comprising:

supplying a current to the panel;

receiving information on the supplied current;

determining a cumulative current based on the received information;

setting a current limit value such that the supplied current is equal to or less than the set current limit value; and

adjusting the set current limit value to a first limit value or a second limit value based on the determined cumulative current, wherein the second limit value is less than the first limit value.

15. The operating method of the display device according to claim 14 , wherein the determining the cumulative current comprises determining the cumulative current by summing respective differences between a present current supplied to the panel and a reference value for each set period of time.

16. The operating method of the display device according to claim 14 , wherein the adjusting the set current limit value further comprises:

setting the current limit value to the second limit value when the cumulative current is at or above a decrease condition value, wherein the decrease condition value serves as a reference value for decreasing the current limit value; and

setting the current limit value to the first limit value when the cumulative value is less than an increase condition value, wherein the increase condition value serves as a reference for increasing the current limit value.

17. The operating method of the display device according to claim 16 , further comprising:

maintaining the current limit value at the first limit value when the current limit value is set to the first limit value and the cumulative current is less than the decrease condition value; and

maintaining the current limit value at the second limit value when the current limit value is set to the second limit value and the cumulative current is at the increase condition value or more.

18. The operating method of the display device according to claim 14 , further comprising:

correcting the cumulative current to a preset minimum value when the cumulative current is less than the preset minimum value.