Display device and driving method thereof

1. A display device, comprising:

an input signal generator generating an input signal comprising one of a plurality of input frequencies corresponding to a respective one of a plurality of operating modes of the display device;

a main operating clock generator generating a main operating clock using the input signal and a reference signal, a main frequency of the main operating clock varying in accordance with the input frequency, and a reference frequency of the reference signal being constant irrespective of the operating modes; and

a control signal generator generating a control signal using the main operating clock, the control signal changing in accordance with the main frequency and including a source sampling clock (SSC), a gate shift clock (GSC), a source start pulse (SSP), a source output enable (SOE), a gate start pulse (GSP), and a gate output enable (GOE), the source sampling clock, the source start pulse, and the source output enable being transmitted to a data driver, and the gate shift clock, the gate start pulse and the gate output enable being transmitted to a gate driver,

wherein the main operating clock generator includes:

a divider receiving the input signal directly from the input signal generator and dividing the input frequency of the input signal by a division ratio to generate a divided signal,

a phase detector comparing a frequency of the divided signal with the reference frequency of the reference signal to generate a compared signal,

a pulse-to-voltage converter converting the compared signal into a control voltage, and

a voltage controlled oscillator generating the main operating clock comprising the main frequency corresponding to a level of the control voltage, and

wherein the control signal generator and the input signal generator forms form a timing controller.

2. The device of claim 1 , wherein the division ratio of the divider is constant regardless of the operating modes.

3. The device of claim 1 , further comprising a decoder decoding a data signal inputted thereto in accordance with the control signal.

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

generating an input signal comprising one of a plurality of input frequencies corresponding to a respective one of a plurality of operating modes of a display device;

generating a main operating clock using the input signal and a reference signal through a main operating clock generator, including varying a main frequency of the main operating clock in accordance with the input frequency while keeping constant a reference frequency of the reference signal irrespective of the operating modes; and

generating a control signal using the main operating clock, including changing the control signal in accordance with the main frequency, the control signal including a source sampling clock (SSC), a gate shift clock (GSC), a source start pulse (SSP), a source output enable (SOE), a gate start pulse (GSP), and a gate output enable (GOE), the source sampling clock, the source start pulse, and the source output enable is transmitted to a data driver, and the gate shift clock, the gate start pulse and the gate output enable being transmitted to a gate driver,

wherein generating the main operating clock through the main operating clock generator includes:

receiving the input signal directly from an input signal generator and dividing the input frequency of the input signal by a division ratio to generate a divided signal through a divider,

comparing a frequency of the divided signal with the reference frequency of the reference signal to generate a compared signal through a phase detector,

converting the compared signal into a control voltage through a pulse-to-voltage converter, and

generating the main operating clock comprising the main frequency corresponding to a level of the control voltage through a voltage controlled oscillator, and

wherein a control signal generator generating the control signal and the input signal generator generating the input signal form a timing controller.

5. The method of claim 4 , further comprising keeping the division ratio constant regardless of the selected operating mode.

6. A driving circuit for a display device, comprising:

an input signal generator generating an input signal comprising one of a plurality of input frequencies corresponding to a respective one of a plurality of operating modes of the display device;

a main operating clock generator responsive to the one of the plurality of input frequencies to generate a main operating clock, a main frequency of the main operating clock varying in accordance with the one of the plurality of frequencies; and

a control signal generator generating a control signal using the main operating clock, the control signal changing in accordance with the main frequency, the control signal including a source sampling clock (SSC), a gate shift clock (GSC), a source start pulse (SSP), a source output enable (SOE), a gate start pulse (GSP), and a gate output enable (GOE), the source sampling clock, the source start pulse, and the source output enable being transmitted to a data driver, and the gate shift clock, the gate start pulse and the gate output enable being transmitted to a gate driver,

wherein the main operating clock generator is responsive to a reference signal comprising a constant reference frequency irrespective of the operating modes,

wherein the main operating clock generator includes:

a divider receiving the input signal directly from the input signal generator and dividing the input frequency of the input signal by a division ratio to generate a divided signal,

a phase detector comparing a frequency of the divided signal with the reference frequency of the reference signal to generate a compared signal,

a pulse-to-voltage converter converting the compared signal into a control voltage, and

a voltage controlled oscillator generating the main operating clock comprising the main frequency corresponding to a level of the control voltage, and

wherein the control signal generator and the input signal generator form a timing controller.

7. The driving circuit of claim 6 , wherein an input-to-output conversion attribute of the main operating clock generator is constant regardless of the operating modes.