Digital liquid crystal display driving circuit

An LCD driving circuit for driving an LCD to display a video image, comprising:

• a digital gamma-correction and inversion circuit, coupled to directly receive a digitized video signal from a display memory, for performing a digital gamma-correction process on the digitized video signal and then performing a polarity inversion process on selected lines of the gamma corrected video signal;
• a digital-to-analog conversion means, coupled to said digital gamma-correction and inversion circuit, for converting the digital output of said digital gamma-correction and inversion circuit into analog form;
• and
• an LCD timing control circuit, coupled to an external time control circuit, said digital gamma-correction and inversion circuit, and said digital conversion means, to directly receive a plurality of video control signals associated with the digitized video signal, for converting the video control signals into an LCD timing control signal to control the display of the digitized video signal on the LCD.

A method for driving an LCD to display a video signal, comprising the steps of:

• directly receiving a digital video signal from a display memory;
• converting a gamma corrected and signal inverted version of the directly received digital video signal to a video signal in analog form for display by an LCD;
• directly receiving video control signals that control the directly received digital video signal;
• driving the LCD with the video control signals;
• supplying power to an LCD that displays the video signal in analog form;
• and shutting down the LCD when the LCD has been idle for a preset period.

A method for driving an LCD to display a video image, comprising the steps of:

• receiving a digitized video signal and a plurality of video control signals, respectively, in an LCD driving circuit to drive the LCD to display the video image;
• performing gamma-correction and polarity inversion in the LCD driving circuit on the digitized video signal to generate a digital output to achieve gamma-correction for the video image to be displayed on the LCD, and to make neighboring lines of the LCD opposite in polarity;
• and processing the video control signals in an LCD timing control circuit of the LCD driving circuit to generate video control signals for driving the LCD;
• wherein the LCD driving circuit further comprises a PWM and shutdown circuit, and wherein the method further comprises;
• receiving an external voltage in the PWM and shutdown circuit;
• and converting the external voltage in the PWM and shutdown circuit to a DC voltage to power the LCD.

An LSI circuit for driving an LCD to display a video image, comprising:

• a digital gamma-correction and inversion circuit receiving a digitized video signal, and performing digital gamma-correction and polarity inversion of the digitized video signal to provide a digital output;
• a digital-to-analog conversion circuit converting the digital output of said gamma-correction and inversion circuit into analog form corresponding to a video image to be displayed;
• an LCD timing control circuit receiving a plurality of timing control signals and providing timing control to said digital gamma-correction and inversion circuit, said digital-to-analog conversion circuit and the LCD;
• and
• a PWM and shutdown circuit supplying power to the LCD and shutting down the LCD when the LCD has been idle for a preset period.

A method of driving an LCD to display a video image, comprising:

• providing in an LSI circuit with a digital gamma-correction and inversion circuit, a digital-to-analog conversion circuit coupled to said digital gamma-correction and inversion circuit, an LCD timing control circuit, and a PWM and shutdown circuit;
• receiving a digitized video signal by the digital gamma-correction and inversion circuit, and performing digital gamma-correction and polarity inversion of the digitized video signal to provide a digital output;
• converting the digital output of said digital gamma-correction and inversion circuit into analog form by the digital-to-analog conversion circuit wherein the analog form corresponds to a video image to be displayed;
• and
• receiving a plurality of timing control signals by the LCD timing control circuit, and providing timing control by the LCD timing control circuit of said digital gamma-correction and inversion circuit, said digital conversion circuit and the LCD;
• and
• supplying power to the LCD the PWM and shutdown circuit, and shutting down the LCD by the PWM and shutdown circuit when the LCD has been idle for a preset period.