Liquid crystal display driving method/driving circuit capable of being driven with equal voltages

• US 8,094,112 B2
• Filed: 02/07/2006
• Issued: 01/10/2012
• Est. Priority Date: 10/15/1992
• Status: Expired due to Fees

• Current Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Original Assignee: Hitachi, Ltd., Hitachi Video & Information System Incorporated
• Inventors: Furuhashi, Tsutomu, Ikeda, Makiko, Kasai, Naruhiko, Futami, Toshio, Suzuki, Tetsuya
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): LAM, NELSON C
• Application Number:
  US11/348,401
• Publication Number:
  US 20060125764A1
• Time in Patent Office: 2,163 Days
• Field of Search: 345 87-104, 345/204
• US Class Current: 345/98
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0876 Supplementary capacities in pixels having special driving circuits and electrodes instead of being connected to common electrode or ground; Use of additional capacitively coupled compensation electrodes
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/027 Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters
• CPC Class Codes: G09G 2310/0281 Arrangement of scan or data electrode driver circuits at the periphery of a panel not inherent to a split matrix structure
• CPC Class Codes: G09G 2310/0289 Details of voltage level shifters arranged for use in a driving circuit
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3655 Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors
• CPC Class Codes: G09G 3/3659 the addressing of the pixel involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependant on signal of two data electrodes
• CPC Class Codes: G09G 3/3688 suitable for active matrices only

Abstract

A display apparatus comprising a plurality of pixel portions arranged in a matrix, a signal driver circuit which generates apply voltages corresponding to display data, and applies the apply voltages to the pixel portions, a scan driver circuit which applies a selecting voltage to selected ones of the pixel portions, and a level shifter circuit which converts a voltage level of the display data into a drive voltage level of the signal driver circuit, thereby producing level-shifted display data. The signal driver circuit generates the apply voltages based on the level-shifted display data.

Claims

1. A display apparatus comprising:

a display panel including a plurality of pixels in a matrix arrangement;

a controlling circuit configured to receive an input analog display data signal having luminance information with a positive-polarity voltage and to output an alternating signal;

a polarity inverting circuit coupled to receive the input analog display data signal from the controlling circuit and to receive the alternating signal, and configured to output an inverted polarity analog image data signal by inverting a polarity of the input analog display data signal in correspondence with the alternating signal;

an AC circuit coupled to receive the alternating signal and configured to output a high-level reference voltage and a low-level reference voltage, wherein a polarity of both of the high-level reference voltage and the low-level reference voltage is reversed with respect to a common electrode voltage according to the alternating signal;

a level shifter circuit coupled to the polarity inverting circuit to receive the inverted polarity analog image data signal and coupled to receive the low-level reference voltage, and configured to shift voltage levels of the inverted analog image data signal according to the low-level reference voltage; and

a signal driver circuit coupled to receive the high-level reference voltage and the low-level reference voltage from the AC circuit and coupled to receive the inverted analog image data signal with shifted voltage levels from the level shifter circuit, and configured to convert the inverted analog image data signal received from the level shifter circuit into a voltage applied to the display panel corresponding to the inverted analog image data signal with shifted voltage levels received from the level shifter circuit.

2. The display apparatus according to claim 1,

wherein the signal driver circuit comprises a low voltage resistant driver circuit.

3. The display apparatus according to claim 1,

wherein the display panel comprises an LCD.

4. A display apparatus comprising:

a display panel including a plurality of pixels in a matrix arrangement;

a controlling circuit configured to receive an input analog display data signal having luminance information which has only a positive-polarity voltage and to output an alternating signal; and

means for driving the display panel based on the input analog display data signal having luminance information which has only a positive-polarity voltage received by the controlling circuit without deterioration of a display image on the display panel based on the input analog display data signal and without analog/digital conversion of the input analog display data signal, said means comprising;

a polarity inverting circuit coupled to receive the input analog display data signal from the controlling circuit and to receive the alternating signal, and configured to output an inverted polarity analog image data signal by inverting a polarity of the input analog display data signal in correspondence with the alternating signal;

an AC circuit coupled to receive the alternating signal and configured to output a high-level reference voltage and a low-level reference voltage, wherein a polarity of both of the high-level reference voltage and the low-level reference voltage is reversed with respect to a common electrode voltage according to the alternating signal;

a level shifter circuit coupled to the polarity inverting circuit to receive the inverted polarity analog image data signal and coupled to receive the low-level reference voltage, and configured to shift voltage levels of the inverted analog image data signal according to the low-level reference voltage; and

a signal driver circuit coupled to receive the high-level reference voltage and the low-level reference voltage from the AC circuit and coupled to receive the inverted analog image data signal with shifted voltage levels from the level shifter circuit, and configured to convert the inverted analog image data signal received from the level shifter circuit into a voltage applied to the display panel corresponding to the inverted analog image data signal with shifted voltage levels received from the level shifter circuit.

5. The display apparatus according to claim 4,

wherein the signal driver circuit comprises a low voltage resistant driver circuit.

6. The display apparatus according to claim 4,

wherein the display panel comprises an LCD.