Organic light emitting display device configured to measure deterioration information, and driving method thereof

Patent metadata

Field	Value
Publication number	US-9691329-B2
Application number	US-201313929722-A
Country	US
Kind code	B2
Filing date	Jun 27, 2013
Priority date	Jan 24, 2013
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

An organic light emitting display device includes pixels positioned at crossing regions between data lines and scan lines, each of the pixels including an organic light emitting diode, a scan driver configured to supply a scan signal to scan lines, a data driver configured to drive the data lines, wherein the data driver includes, in each channel, a supply part comprising a digital-to-analog converter configured to generate data signals using second data supplied from outside in a driving period, and a deterioration part configured to measure deterioration information of the organic light emitting diode using the digital-to-analog converter in a sensing period.

First claim

What is claimed is:

1. An organic light emitting display device comprising:
pixels positioned at crossing regions between data lines and scan lines, each of the pixels comprising an organic light emitting diode;
a scan driver configured to supply a scan signal to scan lines;
a data driver configured to drive the data lines, the data driver comprising, in each channel of the data driver:
a supply part comprising a digital-to-analog converter configured to generate data signals using second data supplied from outside in a driving period, and configured to generate and output an intermediate voltage based on a deterioration data in an initial period of a sensing period, the sensing period occurring before the driving period in a frame period; and
a deterioration part configured to supply a current to the organic light emitting diode to measure deterioration information of the organic light emitting diode, to control a bit value of the deterioration data supplied to the digital-to-analog converter based on the deterioration information in the sensing period, and to supply the deterioration data to the supply part; and

a switching unit configured to switchably connect a corresponding data line of the data lines to the supply part in the driving period, and configured to connect the corresponding data line to the deterioration part in the sensing period.

2. The organic light emitting display device according to claim 1 , wherein the supply part comprises:
a holding latch configured to store the deterioration data from the deterioration part and to store the second data;
the digital-to-analog converter, which is configured to generate an analog voltage corresponding to either the deterioration data or a data signal corresponding to the second data; and
a buffer configured to output the analog voltage or the data signal.

3. The organic light emitting display device according to claim 2 , wherein the deterioration data is configured to be supplied in the sensing period.

4. The organic light emitting display device according to claim 2 , wherein the analog voltage generated by initial deterioration data, which is stored at the holding latch, is set to be the intermediate voltage generated in the digital-to-analog converter.

5. The organic light emitting display device according to claim 2 , further comprising:
a level shifter positioned between the holding latch and the digital-to-analog converter.

6. The organic light emitting display device according to claim 2 , wherein the deterioration part comprises:
a current source configured to supply a current to the organic light emitting diode through the corresponding data line in the sensing period;
a comparator coupled to the buffer and the current source, and configured to compare the analog voltage with a deterioration voltage generated at the organic light emitting diode in response to the supplied current; and
a controller configured to control a bit value of the deterioration data corresponding to the compared result of the comparator.

7. The organic light emitting display device according to claim 6 , wherein the controller is configured to control the bit value of the deterioration data so that the analog voltage and the deterioration voltage are similar to each other.

8. The organic light emitting display device according to claim 6 , further comprising:
a memory configured to store the deterioration data, and
a timing controller configured to generate the second data by changing a bit of first data so that a deterioration of the organic light emitting diode is compensated using the deterioration data.

9. The organic light emitting display device according to claim 2 ,
wherein the deterioration part comprises:
a current source configured to supply a current to the organic light emitting diode through the corresponding data line; and
a comparator coupled to the buffer and the current source, and configured to compare the analog voltage with a deterioration voltage generated at the organic light emitting diode according to the supplied current.

10. The organic light emitting display device according to claim 9 , further comprising:
a timing controller configured to supply the second data to the holding latch in the driving period and to control a bit value of the deterioration data corresponding to the compared result of the comparator in the sensing period.

11. The organic light emitting display device according to claim 10 ,
wherein the timing controller controls a bit value of the deterioration data so that the analog voltage and the deterioration voltage are similar to each other.

12. The organic light emitting display device according to claim 10 , further comprising: a memory configured to store the deterioration data, and the timing controller is configured to generate the second data by changing a bit of first data so that a deterioration of the organic light emitting diode is compensated using the deterioration data stored at the memory.

13. The organic light emitting display device according to claim 10 ,
wherein the deterioration data supplied from the timing controller is supplied to the holding latch through a sampling latch.

14. The organic light emitting display device according to claim 10 ,
wherein the switching unit comprises, in each channel:
a first switching device coupled between the supply part and the corresponding data line and turned on in the driving period, and a second switching device coupled between the deterioration part and the corresponding data line and turned on in the sensing period.

15. The organic light emitting display device according to claim 2 , wherein the switching unit comprises:
a first switching device coupled between the supply part and the corresponding data line, and configured to be turned on in the driving period; and
a second switching device coupled between the deterioration part and the corresponding data line, and configured to be turned on in the sensing period.

16. A method for driving an organic light emitting device comprising:
controlling bits of deterioration data supplied to a digital-to-analog converter connected to a pixel based on deterioration information measured at the pixel, the deterioration information being measured by supplying a current to an organic light emitting diode included in the pixel;
generating an intermediate voltage based on the deterioration data in an initial period of a sensing period;
generating second data by changing first data from outside to compensate for a deterioration of the organic light emitting diode based on the deterioration data;
supplying the second data converted into a data signal using the digital-to-analog converter in a driving period to a data line by switchably connecting the data line to a supply part, the driving period occurring after the sensing period in a frame period; and
connecting the data line to a deterioration part in a sensing period.

17. The method for driving an organic light emitting device according to claim 16 , wherein the controlling bits of deterioration data further comprises:
supplying an initial value of the deterioration data to the digital-to-analog converter and generating an analog voltage from the digital-to-analog converter;
sensing a deterioration voltage applied to the organic light emitting diode while a current is applied to the organic light emitting diode; and
changing the bits of the deterioration data so that the analog voltage and the deterioration voltage are similar to each other.

18. The method for driving an o

Assignees

• Samsung Display Co Ltd
• Korea Advanced Inst Sci & Tech

Inventors

• Kwon Oh-Jo
• Choi Won-Tae
• Ahn Hee-Sun
• Kim Bo-Yeon
• Cho Gyu-Hyeong
• Kim Hyun-Sik
• Bang Jun-Suk

Classifications

• G09G2300/0842

  forming a memory circuit, e.g. a dynamic memory with one capacitor · CPC title

• G09G2320/0295

  by monitoring each display pixel · CPC title

• G09G3/3233

  with pixel circuitry controlling the current through the light-emitting element · CPC title

• G09G2320/045

  Compensation of drifts in the characteristics of light emitting or modulating elements · CPC title

• G09G2300/0819

  used for counteracting undesired variations, e.g. feedback or autozeroing · CPC title