Display device and method for driving the same

1. A display device comprising:

a plurality of pixels, wherein each of the pixels includes a light emitting device, and a pixel circuit coupled to the light emitting device;

a scan driver which supplies a scan signal to the pixel circuit;

a data driver which supplies a data signal to the pixel circuit;

a power supply which supplies a voltage to the pixel circuit;

a timing controller which controls the scan driver;

a first signal generator which provides a first clock signal to the timing controller; and

a second signal generator which provides a second clock signal to the timing controller,

wherein the timing controller controls the scan driver based on the first clock signal to supply a first scan signal to the pixel circuit, and controls the scan driver based on the second clock signal to supply a second scan signal to the pixel circuit,

wherein the first signal generator and the second signal generator are provided independently of each other, so that pulse widths of the first scan signal and the second scan signal are controlled independently of each other, and

wherein the first signal generator and the second signal generator are oscillators.

2. The display device of claim 1 , wherein

the data signal is supplied to the pixel circuit from the data driver, while the first scan signal is being supplied to the pixel circuit, and

the voltage is supplied to the pixel circuit from the power supply, while the second scan signal is being supplied to the pixel circuit.

3. The display device of claim 2 , wherein the first scan signal and the second scan signal are supplied to the pixel circuit, while the light emitting device is not emitting light.

4. The display device of claim 3 , wherein the first scan signal is supplied to the pixel circuit after the second scan signal is supplied to the pixel circuit.

5. The display device of claim 2 , wherein the voltage is an initialization voltage for initializing a gate electrode of a driving transistor in the pixel circuit.

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

a data line to which the data signal is supplied;

a first scan line to which a first scan signal is supplied from the scan driver;

a second scan line to which a second scan signal is supplied from the scan driver; and

a first power voltage supply line to which a first power voltage is supplied from the power supply,

wherein the pixel circuit includes:

a first transistor including a first electrode coupled to the first power voltage supply line, a second electrode, and a first gate electrode coupled to a first node;

a second transistor including a third electrode coupled to the data line, a fourth electrode coupled to a second node, and a second gate electrode coupled to the first scan line; and

a third transistor including a fifth electrode coupled to the first node, a sixth electrode coupled to the second electrode, and a third gate electrode coupled to the second scan line.

7. The display device of claim 6 , wherein the pixel circuit further includes:

a first capacitor coupled between the first power voltage supply line and the second node; and

a second capacitor coupled between the first node and the second node.

8. The display device of claim 7 , further comprising:

a third scan line to which a third scan signal is supplied from the scan driver; and

an initialization voltage supply line to which an initialization voltage is supplied from the power supply,

wherein the pixel circuit further includes a fourth transistor including a seventh electrode coupled to the first node, an eighth electrode coupled to the initialization voltage supply line, and a fourth gate electrode coupled to the third scan line.

9. The display device of claim 8 , wherein

during a period in which the light emitting device does not emit light, the second scan signal is supplied to the pixel circuit after the third scan signal is supplied to the pixel circuit, and the first scan signal is supplied to the pixel circuit after the second scan signal is supplied to the pixel circuit.

10. The display device of claim 8 , wherein each of the first transistor, the second transistor, the third transistor and the fourth transistor is a P-type transistor.

11. The display device of claim 6 , wherein

the first scan signal is supplied from the scan driver when the first clock signal is provided thereto, and

the second scan signal is supplied from the scan driver when the second clock signal is supplied thereto.

12. The display device of claim 11 , wherein the display device is driven with a variable frequency driving using a first frequency and a second frequency, which are different from each other.

13. The display device of claim 12 , wherein a length of a time for which the second scan signal is supplied to the pixel circuit when the display device is driven at the first frequency is equal to a length of a time for which the second scan signal is supplied to the pixel circuit when the display device is driven at the second frequency.

14. The display device of claim 12 , wherein

the first frequency is in a range of about 1 Hz to about 60 Hz, and

the second frequency is in a range of about 120 Hz to about 250 Hz.

15. The display device of claim 14 , wherein

the display device is driven with a variable frequency driving further using a third frequency different from the first frequency and the second frequency,

wherein the third frequency is in a range of about 60 Hz to about 120 Hz.

16. The display device of claim 1 , wherein the first signal generator and the second signal generator are disposed at an outside of the timing controller and the scan driver.

17. A method for driving a display device, which is driven with a variable frequency driving using a first frequency and a second frequency, which are different from each other, the method comprising:

providing, by a first signal generator of the display device, a first clock signal to a timing controller of the display device, and supplying, by a scan driver of the display device, a first scan signal to a pixel circuit of the display device based on the first clock signal, wherein the scan driver is controlled by the timing controller; and

providing, by a second signal generator of the display device, a second clock signal to the timing controller, and supplying, by the scan driver, a second scan signal to the pixel circuit based on the second clock signal,

wherein the first signal generator and the second signal generator are provided independently of each other, so that pulse widths of the first scan signal and the second scan signal are controlled independently of each other, and

wherein the first signal generator and the second signal generator are oscillators.

18. The method of claim 17 , further comprising:

providing, by the first signal generator, the first clock signal to the timing controller, and supplying, by the scan driver, a third scan signal to the pixel circuit based on the first clock signal; and

providing, by the second signal generator, the second clock signal to the timing controller, and supplying, by the scan driver, supplying a fourth scan signal to the pixel circuit based on the second clock signal,

wherein the first scan signal and the second scan signal are supplied to the pixel circuit when the display device is driven at the first frequency,

wherein the third scan signal and the fourth scan signal are supplied to the pixel circuit when the display device is driven at the second frequency,

wherein a length of a time for which the first scan signal is supplied to the pixel circuit is different from a length of a time for which the third scan signal is supplied to the pixel circuit, and

a length of the time for which the second scan signal is supplied to the pixel circuit is equal to length of a time for which the fourth scan signal is supplied to the pixel circuit.