Liquid Crystal Driver, Liquid Crystal Display Device, and Liquid Crystal Driving Method
AssigneePanasonic Corporation
InventorsMasami Tanaka, Kazuyoshi Nishi
Life of this patent
Estimating the term…
Abstract
A selector (103A) outputs a gray level voltage corresponding to pixel data (D-A) as drive voltage (Va). When the drive voltage (Va) is written in a source line (LineS-A), switches (105A-1, 105A-2) are ON while a switch (106A) is OFF. When the drive voltage (Va) written in the source line (LineS-A) is retained, the switches (105A-1,105A-2) are OFF while the switch (106A) is ON.
Claims10
A liquid crystal driver for driving a liquid crystal display panel which includes P source lines (P is a natural number), the driver comprising:
- a gray level voltage generator for generating N gray level voltages which have different voltage values from one another (N is a natural number);
- an operational amplifier for amplifying an input voltage;
- P selectors corresponding to the P source lines;
- P connection switching sections corresponding to the P selectors;
- and
- a controller for controlling the P connection switching sections,
- wherein each of the P selectors receives pixel data indicative of a gray level to select one of the N gray level voltages generated by the gray level voltage generator which corresponds to the pixel data and outputs the selected gray level voltage,
- each of the P connection switching sections has a voltage write mode and a voltage retention mode,
- in the voltage write mode, each of the connection switching sections supplies an output of a corresponding one of the P selectors to the operational amplifier and supplies an output of the operational amplifier to a corresponding one of the P source lines,
- in the voltage retention mode, each of the connection switching sections supplies an output of a corresponding one of the P selectors to a corresponding one of the P source lines, and
- the controller sets any one of the P connection switching sections into the voltage write mode at least once;
- after passage of a first predetermined interval, shifts the connection switching section from the voltage write mode to the voltage retention mode;
- and after the mode shift in each of the P connection switching sections is completed, maintains all of the P connection switching sections in the voltage retention mode until a second predetermined interval is passed.
2-5. (canceled)
A liquid crystal driver for driving a liquid crystal display panel which includes P source lines (P is a natural number), the driver comprising:
- a gray level voltage generator for generating N gray level voltages which have different voltage values from one another (N is a natural number);
- an operational amplifier for amplifying an input voltage;
- P selectors corresponding to the P source lines;
- P first switches corresponding to the P selectors;
- P second switches corresponding to the P source lines;
- and
- P third switches corresponding to the P selectors,
- wherein each of the P selectors receives pixel data indicative of a gray level to select one of the N gray level voltages generated by the gray level voltage generator which corresponds to the pixel data and outputs the selected gray level voltage,
- each of the P first switches is connected between a corresponding one of the P selectors and the operational amplifier,
- each of the P second switches is connected between a corresponding one of the P source lines and the operational amplifier, and
- each of the P third switches is connected between a corresponding one of the P selectors and a corresponding one of the P source lines.
A method for driving a liquid crystal display panel which includes P source lines (P is a natural number), the method comprising the steps of:
- (A) generating N gray level voltages which have different voltage values from one another (N is a natural number);
- (B) receiving pixel data indicative of a gray level to select one of the N gray level voltages generated at step (A) which corresponds to the pixel data;
- (C) amplifying the gray level voltage selected at step (B) to supply the amplified gray level voltage to any one of the P source lines;
- and
- (D) after step (C), supplying the gray level voltage selected at step (B) to the source line.
Dependencies are inferred from the claim text.