Display device and method of driving the same
A display device of the disclosure includes a display panel including pixels, a first sensor configured to sense mobility of the pixels, and a second sensor. The first sensor generates an initial sensing value using a first process to sense the mobility during a first time period from a power-on time point of the display device to a display start time point, and generates a first sensing value using a second process to sense the mobility after the display start time point. The second sensor senses whether the display panel is an abnormal state based on the initial sensing value and the first sensing value.
1. A display device comprising:
a display panel including pixels;
a first sensor configured to sense mobility of the pixels; and
a second sensor,
wherein the first sensor generates an initial sensing value using a first process to sense the mobility during a first period from a power-on time point of the display device to a display start time point, and generates a first sensing value using a second process to sense the mobility during a second period after the display start time point, and
wherein the second sensor senses whether the display panel is in an abnormal state based on the initial sensing value and the first sensing value.
2. The display device according to claim 1 , wherein a processing time of the first process is shorter than a processing time of the second process.
3. The display device according to claim 1 , further comprising:
a scan driver connected to the pixels through scan lines,
wherein the scan driver sequentially supplies scan signals to the scan lines while the first process is performed.
4. The display device according to claim 3 , wherein the first sensor performs the second process during blank periods positioned between active periods, and
wherein the scan driver supplies the scan signals to the scan lines different from each other during the blank periods different from each other while the second process is performed.
5. The display device according to claim 4 , further comprising:
a data driver connected to the pixels through data lines,
wherein the data driver first supplies sensing voltages to the data lines and then supplies data voltages to the data lines during each of the blank periods while the second process is performed.
6. The display device according to claim 5 , wherein the data voltages supplied during the blank periods are the same as some of the data voltages supplied during previous active periods.
7. The display device according to claim 5 , wherein the data driver successively supplies the sensing voltages and does not supply the data voltages while the first process is performed.
8. The display device according to claim 1 , wherein the second sensor comprises a selection circuit configured to select one of a first mode and a second mode according to a number of times a process is performed to sense the mobility.
9. The display device according to claim 8 , wherein the selection circuit selects the first mode when only the first process and the second process are performed, and selects the second mode when a process is performed to sense the mobility after the second process is performed.
10. The display device according to claim 9 , wherein the second sensor further comprises a calculator calculating a difference value between the initial sensing value and the first sensing value during the first mode and calculating the difference value between sensing values generated in two recent mobility sensing processes during the second mode.
11. The display device according to claim 10 , wherein the second sensor further comprises a first logic circuit designating corresponding pixels as abnormal pixel candidates when the difference value is greater than a first threshold value.
12. The display device according to claim 11 , wherein the second sensor further comprises a second logic circuit determining the abnormal pixel candidates as abnormal pixels when sensing values corresponding to the abnormal pixel candidates are greater than a second threshold value.
13. The display device according to claim 12 , wherein the second sensor further comprises a third logic circuit determining that the display panel is in the abnormal state when the number of the abnormal pixels is greater than a first count threshold value and determining that the display panel is in a normal state when the number of the abnormal pixels is less than the first count threshold value.
14. The display device according to claim 12 , wherein the second further comprises:
a first counter generating a first abnormal condition value when the number of the abnormal pixels is greater than a first count threshold value;
a second counter generating a second abnormal condition value when the number of the abnormal pixels belonging to a first pixel group connected to different scan lines and one data line is greater than a second count threshold value; and
a third counter generating a third abnormal condition value when the number of the abnormal pixels belonging to a second pixel group positioned in a partial area of the display panel and connected to a plurality of scan lines and a plurality of data lines is greater than a third count threshold value, and
wherein the second sensor determines that the display panel is in the abnormal state when at least one of the first abnormal condition value, the second abnormal condition value, and the third abnormal condition value is generated.
15. A method of driving a display device, the method comprising:
generating an initial sensing value using a first process to sense a mobility of pixels of a display panel of the display device during a first period from a power-on time point of the display device to a display start time point;
generating a first sensing value using a second process to sense the mobility after the display start point; and
sensing whether the display panel is in an abnormal state based on the initial sensing value and the first sensing value.
16. The method according to claim 15 , wherein a processing time of the first process is shorter than a processing time of the second process.
17. The method according to claim 15 , further comprising:
sequentially supplying scan signals to scan lines connected to the pixels while the first process is performed.
18. The method according to claim 17 , wherein the second process is performed during blank periods positioned between active periods, and
the method further comprises supplying the scan signals to the scan lines different from each other during the blank periods different from each other while the first second process is performed.
19. The method according to claim 18 , further comprising:
supplying sensing voltages to data lines connected to the pixels during each of the blank periods while the second process is performed, and then, supplying data voltages to the data lines.
20. The method according to claim 19 , wherein the data voltages supplied during the blank periods are the same as some of the data voltages supplied during previous active periods.