Controller driver and display apparatus using the same

• US 7,292,235 B2
• Filed: 06/02/2004
• Issued: 11/06/2007
• Est. Priority Date: 06/03/2003
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: NEC Electronics Corporation (Renesas Electronics Corporation)
• Inventors: Nose, Takashi
• Primary Examiner(s): Shalwala, Bipin
• Assistant Examiner(s): Kovalick, Vincent E.
• Application Number:
  US10/857,914
• Publication Number:
  US 20040246244A1
• Time in Patent Office: 1,252 Days
• Field of Search: 345/1.1, 345/204, 345/531, 345/532, 345/544, 348/564, 348/571, 348/588
• US Class Current: 345/204
• CPC Class Codes: G09G 2310/0275 Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
• CPC Class Codes: G09G 2320/0271 Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping
• CPC Class Codes: G09G 2340/145 related to small screens
• CPC Class Codes: G09G 5/346 for systems having a bit-mapped display memory
• CPC Class Codes: G09G 5/39 Control of the bit-mapped memory
• CPC Class Codes: G09G 5/393 Arrangements for updating the contents of the bit-mapped memory
• CPC Class Codes: G09G 5/395 Arrangements specially adapted for transferring the contents of the bit-mapped memory to the screen G09G5/399 takes precedence

Abstract

A control driver includes a display memory control section which generates a first process control signal when image data includes only first image data which has a pixel size equal to or smaller than that of a display section, and generates a second process control signal when the image data includes first image data and second image data and the first image data has a pixel size equal to that of the display section, and a display memory section which stores upper and lower portions of the first image data as first and second portions of display data in response to the first process control signal, and stores the upper portion of the first image data and an upper portion of the second image data as the first and second portions of the display data in response to the second process control signal. The display data is displayed on the display section.

Claims

1. A control driver comprising:

a display memory control section which generates a first process control signal when image data comprises only fist image data which has a pixel size equal to or smaller than that of a display section, and generates a second process control signal when said image data comprises first image data and second image data and said first image data has a pixel size is equal to that of said display section; and

a display memory section which stores upper and lower portions of said first image data as first and second portions of display data in response to said first process control signal, and stores said upper portion of said first image data and an upper portion of said second image data as said first and second portions of said display data in response to said second process control signal,

wherein said display data is displayed on said display section.

2. The control driver according to claim 1, wherein a number of bits of said upper portion of said first image data is optional.

3. A control driver comprising:

a display memory section which stores first and second portions of display data, wherein said first and second portions are upper and lower portions of a first image data in a first process when image data comprises only said first image data has a pixel size equal to or smaller than that of a display section on which said display data is displayed, and said first and second portions are said upper portion of said first image data and an upper portion of a second image data in a second process, when said image data comprises said first image data and second image data and said first image data has the pixel size equal to that of said display section;

a first selector section which outputs as said second portion, said lower portion of said first image data in said first process and said upper portion of said second image data in said second process to said display memory section;

a latch section which latches data supplied thereto;

a second selector section which outputs said first portion of said display data read out from said display memory section to said latch section in said first process, and said first portion of said read out display data for display of said first image data and said second portion of said read out display data for display of said second image data in said second process; and

a third selector section which outputs said second portion of said display data to said latch section in said first process, and said first portion of said read out display data for display of said first image data and said second portion of said read out display data for display of said second image data in said second process.

4. The control driver according to claim 3, further comprising:

a data line driving circuit which drives data lines of said display section, based on gradation voltages and the latched data by said latch section.

5. The control driver according to claim 3, wherein said display memory section comprises:

a first display memory which stores said first portion of said display data; and

a second display memory which stores said second portion of said display data.

6. The control driver according to claim 5, wherein said display memory section comprises:

a plurality of memory cells arranged in a matrix of columns and rows,

said first display memory is formed from odd numbered columns, and

said second display memory is formed from even numbered columns.

7. The control driver according to claim 6, wherein said second selector section comprises a plurality of second selectors which are provided for said odd numbered columns;

and

said third selector section comprises a plurality of third selectors which are provided for said even numbered columns,

said odd numbered column for one of data bits of said first portion of said display data is provided in neighbor to said even numbered column for a data bit of said second portion corresponding to said data bit of said first portion,

said data bit read out from said odd numbered column is connected with said second and third selectors corresponding to said odd numbered column and said even numbered column, and

said data bit read out from said even numbered column is connected with said second and third selectors corresponding to said odd numbered column and said even numbered column.

8. The control driver according to claim 6, wherein rows of said memory cells of said odd numbered columns are connected with first word lines,

rows of said memory cells of said even numbered columns are connected with second word lines, and

said display memory section further comprises:

a word line decoder which selects one of said first word lines and one of said second word lines based on one of a write address and a read address.

9. The control driver according to claim 8, wherein said word line decoder selects one of said first word lines and one of said second word lines at a time based on said write address for a write operation of said first image data and based on said read address for a read operation of said first image data in said first process,

said word line decoder selects one of said first word lines based on a first write address for a write operation of said upper portion of said first image data and selects one of said second word lines based on a second write address for a write operation of said upper portion of said second image data, and

said word line decoder selects one of said first word lines based on a first read address for a read operation of said upper portion of said first image data and selects one of said second word lines based on a second read address for a write operation of said upper portion of said second image data.

10. A display apparatus comprising:

an image drawing unit which outputs an image data of a first image data or of said first image data and a second image data;

a gradation voltage generating circuit which generates gradation voltages;

a display section which is connected data lines; and

a control driver, which comprises;

a display memory control section which generates a first process control signal when said image data comprises only fist image data which has a pixel size equal to or smaller than that of said display section, and generates a second process control signal when said image data comprises first image data and said second image data and said first image data has a pixel size is equal to that of said display section; and

a display memory section which stores upper and lower portions of said first image data as first and second portions of display data in response to said first process control signal, and stores said upper portion of said first image data and an upper portion of said second image data as said first and second portions of said display data in response to said second process control signal,

wherein said display data is displayed on said display section based on said gradation voltages.

11. The display apparatus according to claim 10, wherein said control driver further comprises:

a first selector section which outputs as said second portion, said lower portion of said first image data to said display memory section in said first process control signal and said upper portion of said second image data to said display memory section in said second process control signal;

a latch section which latches data supplied thereto;

a second selector section which outputs said first portion of said display data read out from said display memory section to said latch section in response to said first process control signal, and said first portion of said read out display data for display of said first image data and said second portion of said read out display data for display of said second image data in said second process control signal; and

a third selector section which outputs said second portion of said display data to said latch section in said first process control signal, and said first portion of said read out display data for display of said first image data and said second portion of said read out display data for display of said second image data in said second process control signal.

12. The display apparatus according to claim 10, wherein said control driver further comprises:

a data line driving circuit which drives said data lines of said display section based on gradation voltages and the latched data by said latch section.

13. The display apparatus according to claim 10, wherein said display memory section comprises:

a first display memory which stores said first portion of said display data; and

a second display memory which stores said second portion of said display data.

14. The display apparatus according to claim 13, wherein said display memory section comprises:

a plurality of memory cells arranged in a matrix of columns and rows,

said first display memory is formed from odd numbered columns, and

said second display memory is formed from even numbered columns.

15. The display apparatus according to claim 14, wherein said second selector section comprises a plurality of second selectors which are provided for said odd numbered columns;

and

said third selector section comprises a plurality of third selectors which are provided for said even numbered columns,

said odd numbered column for one of data bits of said first portion of said display data is provided in neighbor to said even numbered column for a data bit of said second portion corresponding to said data bit of said first portion,

said data bit read out from said odd numbered column is connected with said second and third selectors corresponding to said odd numbered column and said even numbered column, and

said data bit read out from said even numbered column is connected with said second and third selectors corresponding to said odd numbered column and said even numbered column.

16. The display apparatus according to claim 14, wherein rows of said memory cells of said odd numbered columns are connected with first word lines,

rows of said memory cells of said even numbered columns are connected with second word lines, and

said display memory section further comprises:

a word line decoder which selects one of said first word lines and one of said second word lines based on one of a write address and a read address.

17. The display apparatus according to claim 16, wherein said word line decoder selects one of said first word lines and one of said second word lines at a time based on said write address for a write operation of said first image data and based on said read address for a read operation of said first image data in said first process,

said word line decoder selects one of said first word lines based on a first write address for a write operation of said upper portion of said first image data and selects one of said second word lines based on a second write address for a write operation of said upper portion of said second image data, and

said word line decoder selects one of said first word lines based on a first read address for a read operation of said upper portion of said first image data and selects one of said second word lines based on a second read address for a write operation of said upper portion of said second image data.

18. A mobile terminal comprising:

an input unit used to supply an image data and a scroll instruction; and

a display apparatus,

wherein said display apparatus comprises;

an image drawing unit which outputs an image data of a first image data or of said first image data and a second image data;

a gradation voltage generating circuit which generates gradation voltages;

a display section which is connected data lines, wherein said first image data has a same pixel size as that of said display section; and

a control driver,

wherein said control driver comprises;

a display memory control section which generates a first process control signal when said image data comprises only fist image data which has a pixel size equal to or smaller than that of said display section, and generates a second process control signal when said image data comprises first image data and said second image data and said first image data has a pixel size is equal to that of said display section; and

a display memory section which stores upper and lower portions of said first image data as first and second portions of display data in response to said first process control signal, and stores said upper portion of said first image data and an upper portion of said second image data as said first and second portions of said display data in response to said second process control signal,

wherein said display data is displayed on said display section based on said gradation voltages.

19. The mobile terminal according to claim 18, wherein said control driver further comprises:

a first selector section which outputs as said second portion, said lower portion of said first image data to said display memory section in said first process control signal and said upper portion of said second image data to said display memory section in said second process control signal;

a latch section which latches data supplied thereto;

a second selector section which outputs said first portion of said display data read out from said display memory section to said latch section in response to said first process control signal, and said first portion of said read out display data for display of said first image data and said second portion of said read out display data for display of said second image data in said second process control signal; and

a third selector section which outputs said second portion of said display data to said latch section in said first process control signal, and said first portion of said read out display data for display of said first image data and said second portion of said read out display data for display of said second image data in said second process control signal.

20. The mobile terminal according to claim 18, wherein said control driver further comprises:

a data line driving circuit which drives said data lines of said display section based on gradation voltages and the latched data by said latch section.

21. The mobile terminal according to claim 18, wherein said display memory section comprises:

a first display memory which stores said first portion of said display data; and

a second display memory which stores said second portion of said display data.

22. The mobile terminal according to claim 21, wherein said display memory section comprises:

a plurality of memory cells arranged in a matrix of columns and rows,

said first display memory is formed from odd numbered columns, and

said second display memory is formed from even numbered columns.

23. The mobile terminal according to claim 22, wherein said second selector section comprises a plurality of second selectors which are provided for said odd numbered columns;

and

said third selector section comprises a plurality of third selectors which are provided for said even numbered columns,

said odd numbered column for one of data bits of said first portion of said display data is provided in neighbor to said even numbered column for a data bit of said second portion corresponding to said data bit of said first portion,

said data bit read out from said odd numbered column is connected with said second and third selectors corresponding to said odd numbered column and said even numbered column, and

said data bit read out from said even numbered column is connected with said second and third selectors corresponding to said odd numbered column and said even numbered column.

24. The mobile terminal according to claim 22, wherein rows of said memory cells of said odd numbered columns are connected with first word lines,

rows of said memory cells of said even numbered columns are connected with second word lines, and

said display memory section further comprises:

a word line decoder which selects one of said first word lines and one of said second word lines based on one of a write address and a read address.

25. The mobile terminal according to claim 24, wherein said word line decoder selects one of said first word lines and one of said second word lines at a time based on said write address for a write operation of said first image data and based on said read address for a read operation of said first image data in said first process,

said word line decoder selects one of said first word lines based on a first write address for a write operation of said upper portion of said first image data and selects one of said second word lines based on a second write address for a write operation of said upper portion of said second image data, and

said word line decoder selects one of said first word lines based on a first read address for a read operation of said upper portion of said first image data and selects one of said second word lines based on a second read address for a write operation of said upper portion of said second image data.

26. A method of displaying an image data on a display section, comprising:

determining whether a pixel size of said image data is larger than a pixel size of said display section;

writing upper and lower portions of a first image data in first and second display memories when the pixel size of said image data is not larger than that of said display section and said image data contains only said first image data;

writing said upper portion of said first image data in said first display memory when the pixel size of said image data is larger than that of said display section and said image data contains said first image data and a second image data; and

writing an upper portion of said second image data in said second display memory after the write of said upper portion of said first image data.

27. The method of displaying an image data on a display section, according to claim 26, further comprising:

reading out said upper and lower portions of said first image data from said first and second display memories such that said image data is displayed on said display section in a full gradation, when the pixel size of said image data is not larger than that of said display section and said image data contains only said first image data;

reading out said upper portion of said first image data from said first display memory such that said first image data is displayed on said display section in a half gradation, when the pixel size of said image data is not larger than that of said display section and said image data contains said first image data and said second image data; and

reading out said upper portion of said first image data from said first display memory such that said first and second image data are displayed on said display section in said half gradation, in response to a scroll instruction after the read of said upper portion of said first image data.

28. The method of displaying an image data on a display section, according to claim 26, wherein a number of bits of said upper portion of said first image data is optional.