Driving device and driving method for a light emitting device, and a display panel and display device having the driving device

• US 20050259703A1
• Filed: 05/14/2005
• Published: 11/24/2005
• Est. Priority Date: 05/19/2004
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.), Seoul National University Industry Foundation (Seoul National University)
• Original Assignee: Samsung Electronics Co. Ltd., Seoul National University Industry Foundation (Seoul National University)
• Inventors: You, Bong-Hyun, Han, Min-Koo
• Granted Patent: US 7,616,178 B2
• Time in Patent Office: Days
• US Class Current: 372/38.70
• CPC Class Codes: G09G 2300/0417 Special arrangements specific to the use of low carrier mobility technology
• CPC Class Codes: G09G 2300/0814 used for selection purposes, e.g. logical AND for partial update
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than one capacitor
• CPC Class Codes: G09G 2310/02 Addressing, scanning or driving the display screen or processing steps related thereto
• CPC Class Codes: G09G 2310/0254 Control of polarity reversal in general, other than for liquid crystal displays
• CPC Class Codes: G09G 2310/0262 The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element

Abstract

A driving device and driving method for a light emitting device, and a display panel and display having the driving device are provided. In a display device having a light emitting diode, first and second driving parts are connected to the light emitting diode. A first switching part applies a first data voltage having a first direction and a second data voltage having a second direction opposite the first direction to the first and second driving parts, respectively, during a first frame. A second switching part applies the second data voltage and the first data voltage to the first and second driving parts, respectively, during a second frame.

Claims

1. A driving device for controlling a current applied to a light emitting diode, comprising:

a first driver connected to the light emitting diode;

a second driver connected to the light emitting diode;

a first switch for being activated during a first frame to apply a first data voltage and a second data voltage to the first driver and the second driver, respectively, the first data voltage having a first direction and the second data voltage having a second direction opposite the first direction; and

a second switch for being activated during a second frame to apply the second data voltage and the first data voltage to the first driver and the second driver, respectively.

2. The driving device of claim 1, wherein the first driver applies the current to the light emitting diode in response to the first data voltage during the first frame, and is recovered in response to the second data voltage during the second frame.

3. The driving device of claim 1, wherein the first driver comprises:

a first storage capacitor having a first terminal connected to the first switch and a second terminal connected to a bias line; and

a first driving transistor for controlling a level of a bias voltage to supply the current to the light emitting diode in response to the first data voltage applied from the first switch through a control electrode of the first switch during the first frame, and for being recovered in response to the second data voltage applied from the second switch through the control electrode of the second switch during the second frame.

4. The driving device of claim 3, wherein the first driving transistor is deteriorated by the first data voltage having the first direction and annealed by the second data voltage having the second direction.

5. The driving device of claim 3, wherein the first driving transistor is an amorphous silicon thin-film-transistor (TFT).

6. The driving device of claim 1, wherein the second driver applies the current to the light emitting diode in response to the first data voltage during the second frame, and is recovered in response to the second data voltage during the first frame.

7. The driving device of claim 6, wherein the second driver comprises:

a second storage capacitor having a first terminal connected to the second switch and a second terminal connected to a bias line; and

a second driving transistor for being recovered in response to the second data voltage applied from the first switch through a control electrode of the first switch during the first frame, and for controlling a level of a bias voltage to supply the current to the light emitting diode in response to the first data voltage applied from the second switch through the control electrode of the second switch during the second frame.

8. The driving device of claim 7, wherein the second driving transistor is deteriorated by the first data voltage having the first direction and annealed by the second data voltage having the second direction.

9. The driving device of claim 7, wherein the second driving transistor is an amorphous silicon TFT.

10. The driving device of claim 1, wherein the first switch comprises:

a first switching transistor having a first current electrode connected to a first data line for transmitting the first data voltage, a control electrode connected to a first scan line, and a second current electrode connected to the first driver; and

a second switching transistor having a first current electrode connected to a second data line for transmitting the second data voltage, a control electrode connected to the first scan line, and a second current electrode connected to the second driver.

11. The driving device of claim 10, wherein the first and second switching transistors are amorphous silicon TFTs.

12. The driving device of claim 1, wherein the second switch comprises:

a third switching transistor having a first current electrode connected to a first data line for transmitting the first data voltage, a control electrode connected to a second scan line, and a second current electrode connected to the second driver; and

a fourth switching transistor having a first current electrode connected to a second data line for transmitting the second data voltage, a control electrode connected to the second scan line, and a second current electrode connected to the first driver.

13. The driving device of claim 12, wherein the third and fourth switching transistors are amorphous silicon TFTs.

14. A method of driving a light emitting diode having a first transistor comprising a first current electrode connected to a bias voltage and a second current electrode connected to the light emitting diode, and a second transistor comprising a third current electrode connected to the bias voltage and a fourth current electrode connected to the light emitting diode, the method comprising:

receiving a first scan signal at a first level during a first frame;

applying a first data voltage of a first direction and a second data voltage of a second direction to a control electrode of the first transistor and a control electrode of the second transistor, respectively, in response to the first scan signal;

receiving a second scan signal at a second level during a second frame; and

applying the second data voltage of the second direction and the first data voltage of the first direction to the control electrode of the first transistor and the control electrode of the second transistor, respectively, in response to the second scan signal.

15. The driving method of claim 14, further comprising:

sequentially charging the first data voltage and the second data voltage in response to the first scan signal.

16. The driving method of claim 14, further comprising:

sequentially charging the second data voltage and the first data voltage in response to the second scan signal.

17. The driving method of claim 14, wherein the first transistor is deteriorated while applying the bias voltage to the light emitting diode in response to the first data voltage, and annealed in response to the second data voltage to recover the deterioration of the first transistor, wherein the deterioration occurs during the first frame and the annealing occurs during the second frame.

18. The driving method of claim 14, wherein the second transistor is annealed in response to the second data voltage to recover a deterioration of the second transistor, and the second transistor is deteriorated while applying the bias voltage to the light emitting diode in response to the first data voltage, wherein the annealing occurs during the first frame and the deterioration occurs during the second frame.

19. A display panel comprising:

a first data line for transmitting a first data signal of a first direction;

a second data line for transmitting a second data signal of a second direction;

a bias line for transmitting a bias voltage;

a first scan line for transmitting a first scan signal;

a second scan line for transmitting a second scan signal;

a light emitting diode formed in a region defined by two adjacent data lines and two adjacent scan lines; and

a driver formed in the region to control a driving current applied to the light emitting diode in response to the first data signal when the first scan line is activated, and to control the driving current applied to the light emitting diode in response to the first data signal when the second scan line is activated.

20. The display panel of claim 19, wherein the driver is recovered by the second data signal when the first scan line is activated.

21. The display panel of claim 19, wherein the driver is recovered by the second data signal when the second scan line is activated.

22. A display device comprising:

a timing controller for outputting an image signal and a timing signal;

a data driver for outputting a first data signal of a first direction and a second data signal of a second direction in response to the image signal;

a scan driver for alternately outputting a first scan signal and a second scan signal during two frames in response to the timing signal; and

a light emitting display panel comprising;

a light emitting diode;

a first transistor connected to the light emitting diode; and

a second transistor connected to the light emitting diode,

wherein the light emitting display panel displays an image in response to the first data signal applied to the first transistor when the first scan signal is applied to the first transistor, and prevents deterioration of the second transistor in response to the second data signal applied to the second transistor, and

wherein the light emitting display panel displays the image in response to the first data signal applied to the second transistor when the first scan signal is applied to the second transistor, and prevents deterioration of the first transistor in response to the second data signal applied to the first transistor.

23. The display device of claim 22, wherein the first data signal is outputted through a different path than that of the second data signal from the data driver.