Display device and driving method thereof suppressing power voltage ripples

A method of driving a display device, the method comprising:

• comparing a power voltage with at least one gamma reference voltage from among a plurality of gamma reference voltages and outputting a resulting comparison value;
• generating a gamma selection signal corresponding to the comparison value;
• selecting a gamma data set corresponding to the gamma selection signal from among a plurality of previously stored gamma data sets, and outputting the selected gamma data set;
• generating a data signal corresponding to input data, using the selected gamma data set and the plurality of gamma reference values;
• and
• displaying an image corresponding to the generated data signal.

A method of driving a display device, the method comprising:

• generating a power voltage from an input voltage;
• generating a common voltage from the power voltage;
• generating a gamma reference voltage from the power voltage;
• generating a plurality of data signals from the gamma reference voltage;
• and
• driving a display panel using a plurality of gate drive voltages, a the plurality of data signals, and the common voltage,
• wherein the gamma reference voltage is generated to correct for a ripple in the power voltage.