Display device and method of operating the same

1. A display device comprising:

a display panel including a plurality of pixels;

a data driver which applies data signals to the display panel;

a scan driver including a plurality of scan stages, which sequentially applies scan signals to the display panel;

an emission driver including an emission stage which sequentially applies emission signals to the display panel;

a controller which controls the scan driver, the emission driver, and the data driver; and

a power supply voltage generator which generates a power supply voltage including high voltages and low voltages, and provides the high voltages having different voltage levels from each other or the low voltages having different voltage levels from each other to at least one selected from the scan stages and the emission stage, wherein

the power supply voltage generator generates a first high voltage, a first low voltage lower than the first high voltage, a second high voltage lower than the first high voltage and higher than the first low voltage, and a second low voltage higher than the first low voltage based on an input voltage,

wherein the second high voltage and the second low voltage are scaled from the first high voltage and the first low voltage, respectively.

2. The display device of claim 1 , wherein the power supply voltage generator includes:

a voltage generating block which generates the first high voltage and the first low voltage based on the input voltage; and

a voltage scaling block which scales the first high voltage to the second high voltage, and scales the first low voltage to the second low voltage.

3. The display device of claim 2 , wherein the scan stages include a writing scan stage, a compensation scan stage, an initialization scan stage, and a bypass scan stage.

4. The display device of claim 3 , wherein a scan start signal of the at least one selected from the scan stages and a scan clock signal of at least one selected from the scan stages are toggled between the second high voltage and the second low voltage.

5. The display device of claim 4 , wherein the voltage scaling block determines magnitudes of the second high voltage and the second low voltage based on previously stored data.

6. The display device of claim 4 , wherein the power supply voltage generator provides the second high voltage and the second low voltage to the compensation scan stage and the initialization scan stage.

7. The display device of claim 6 , wherein scan start signals of the compensation scan stage and the initialization scan stage, and scan clock signals of the compensation scan stage and the initialization scan stage are toggled between the second high voltage and the second low voltage.

8. The display device of claim 6 , wherein the power supply voltage generator provides the first high voltage and the second low voltage to the writing scan stage.

9. The display device of claim 8 , wherein a scan start signal of the writing scan stage and a scan clock signal of the writing scan stage are toggled between the first high voltage and the second low voltage.

10. The display device of claim 6 , wherein an emission start signal of the emission stage and an emission clock signal of the emission stage are toggled between the second high voltage and the second low voltage.

11. The display device of claim 6 , wherein a scan start signal of the bypass scan stage and a scan clock signal of the bypass scan stage are toggled between the second high voltage and the second low voltage.

12. A method of operating a display device, the method comprising:

generating a first high voltage and a first low voltage based on an input voltage;

scaling the first high voltage to a second high voltage lower than the first high voltage, and scaling the first low voltage lower than the first high voltage and second high voltage to a second low voltage higher than the first low voltage; and

providing high voltages having different voltage levels from each other or low voltages having different voltage levels from each other to at least one selected from scan stages and an emission stage of the display device.

13. The method of claim 12 , wherein the scan stages include a writing scan stage, a compensation scan stage, an initialization scan stage, and a bypass scan stage.

14. The method of claim 13 , wherein the scaling the first high voltage to the second high voltage and the scaling the first low voltage to the second low voltage includes determining magnitudes of the second high voltage and the second low voltage based on previously stored data.

15. The method of claim 13 , wherein the providing the high voltages having the different voltage levels from each other or the low voltages having the different voltage levels from each other includes providing the second high voltage and the second low voltage to the compensation scan stage and the initialization scan stage.

16. The method of claim 15 , wherein scan start signals of the compensation scan stage and the initialization scan stage, and scan clock signals of the compensation scan stage and the initialization scan stage are toggled between the second high voltage and the second low voltage.

17. The method of claim 15 , wherein the providing the high voltages having the different voltage levels from each other or the low voltages having the different voltage levels from each other includes providing the first high voltage and the second low voltage to the writing scan stage.

18. The method of claim 17 , wherein a scan start signal of the writing scan stage and a scan clock signal of the writing scan stage are toggled between the first high voltage and the second low voltage.

19. The method of claim 15 , wherein an emission start signal of the emission stage and an emission clock signal of the emission stage are toggled between the second high voltage and the second low voltage.

20. The method of claim 15 , wherein a scan start signal of the bypass scan stage and a scan clock signal of the bypass scan stage are toggled between the second high voltage and the second low voltage.