Patent Grant
7737939
This application claims the benefit of Korean Patent Application No. 10-2006-0004443, filed on Jan. 16, 2006, in the Korean Intellectual Property Office, the disclosure of which is herein incorporated by reference in its entirety.
1. Field of the Invention
The present invention relates to a display driver integrated circuit (IC), and more particularly, to a display driver IC and a display driving method for supporting various driving modes.
2. Description of Related Art
A display driver IC in a mobile device is constructed in one chip. The display driver IC converts digital video data to be displayed on a display panel into analog row data and analog column data having predetermined voltages. The display driver IC scans the row data and column data on the display panel. The column data is scanned to column lines of the display panel and the row data is scanned to row lines of the display panel.
The display driver IC receives the video data through input pads and outputs the row data and column data through output pads. Output pads outputting the column data can be located at the center of one side of the display driver IC and output pads outputting the row data can be located to both sides of the output pads outputting the column data. Interconnection lines connecting the output pads and the row lines of the display panel are arranged on a single layer. To substantially prevent the interconnection lines from being twisted the output pads outputting the row data are located at both ends of one side of the display driver IC.
The column data are simultaneously scanned to column lines corresponding thereto when all the output pads outputting the column data are activated. The row data are sequentially scanned to row lines corresponding thereto through output pads activated in a predetermined order. When first through nth (n is a natural number) row data respectively correspond to the row lines of a display panel, which are arranged in a predetermined order, for example, the first through nth row data are sequentially scanned to the row lines.
The display driver IC activates the output pads corresponding to the row data to scan the row data to the row lines. Here, the display driver IC can sequentially activate the output pads placed at one end of one side of the display driver IC and sequentially activate the output pads located at the other end.
Otherwise, the display driver IC can alternately activate the output pads located at both ends of one side of the display driver IC.
The order of activating output paths of the row data to scan the row data to corresponding row lines is fixed to the display driver IC. Therefore, a need exists for a chip and method for selecting the order of activating the output paths.
According to an embodiment of the present invention, a display driving IC includes an input unit a digital-analog converter and a row data output unit.
The input unit receives digital video data to be displayed on a panel. The digital-analog converter converts the digital video data into analog row data and analog column data respectively scanned to row lines and column lines of the panel. The row data output unit outputs at least one of the row data to a row line corresponding thereto for each row scan clock pulse.
The row data output unit activates output paths for outputting the row data to the row lines in an activation order of a driving mode selected from a plurality of driving modes having different orders of activating the output paths in response to a mode select signal.
According to an embodiment of the present invention, groups of three row data respectively corresponding to three adjacent row lines of 3n (n is a multiple of 2) row lines represent first through nth row data groups, and output paths for outputting the first through nth row data groups to the row lines represent first through nth output path groups the row data output unit activating at least one of the first through nth output path groups for each row scan clock pulse.
The row data output unit includes a plurality of counters and a decoder. The plurality of counters respectively correspond to the plurality of driving modes each driving mode corresponding to a respective activation order. The decoder activates output path groups corresponding to numbers representing the activation order, which are output from a counter selected from the plurality of counters. One of the plurality of counters is selected in response to the mode select signal.
The plurality of driving modes include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activates a first output part including the first through (n/2)th output path groups and a second output part including the {(n/2)+1}th through nth output path groups.
The counters include a first counter outputting the activation order of the first mode and a second counter outputting the activation order of the second mode. One of the first and second counters is selected in response to a logic level of the mode select signal.
The row data output unit includes a plurality of decoders. The plurality of decoders activating the output path groups in the activation orders of the driving modes respectively correspond thereto among the plurality of driving modes. One of the plurality of decoders is selected in response to the mode select signal.
The plurality of driving modes include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activates a first output part including the first through (n/2)th output path groups and a second output part including the {(n/2)+1}th through nth output path groups.
The decoders include a first decoder activating the output path groups in the activation order of the first mode and a second decoder activating the output path groups in the activation order of the second mode. One of the first and second decoders is selected in response to a logic level of the mode select signal.
The display driver IC drives an STN panel including 132 row lines.
The display driver IC further includes a mode select signal generator transmitting the mode select signal to the row data output unit in response to a control signal. The input unit includes a plurality of pads receiving the video data and the control signal. The control signal is applied to the display driver IC as different voltages. The control signal may be provided by an external control unit.
The row data output unit sequentially scans the row data to corresponding row lines in the order of a scan mode. The display driver IC further includes a column data output unit simultaneously outputting the column data to the column lines.
According to another embodiment of the present invention, a display driving method using a display driver IC includes receiving digital video data to be displayed on a panel, converting the digital video data into analog row data and analog column data respectively scanned to row lines and column lines of the panel selecting one of a plurality of driving modes having different orders of activating output paths, activating the output paths in the order of the selected driving mode, and outputting at least one of the row data to a row line corresponding thereto through the activated output paths.
The activating of the output paths in the order of the selected driving mode activates at least one of first through nth output path groups for each row scan clock pulse, wherein groups of three row data respectively corresponding to three adjacent row lines of 3n (n is a multiple of 2) row lines represent first through nth row data groups, and wherein the output paths outputting the first through nth row data groups to the row lines represent first through nth output path groups.
A plurality of counters of the display driver IC output the activation orders of driving modes corresponding thereto among the plurality of driving modes. The activating of the output paths in the order of the selected driving mode activates the output paths in an activation order output from a counter corresponding to the selected driving mode among the plurality of counters.
The plurality of driving modes include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activating a first output part including the first through (n/2)th output path groups and a second output part including the {(n/2)+1}th through nth output path groups.
The plurality of counters include a first counter outputting the activation order of the first mode and a second counter outputting the activation order of the second mode.
A plurality of decoders of the display driver IC activate the output path groups in the orders of driving modes respectively corresponding thereto among the plurality of driving modes. The activating of the output paths in the order of the selected driving mode activates the output paths by a decoder corresponding to the selected driving mode among the plurality of decoders.
The plurality of driving modes include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activates a first output part including the first through (n/2)th output path groups and a second output part including the {(n/2)+1}th through nth output path groups.
The plurality of decoders include a first decoder activating the output path groups in the activation order of the first mode and a second decoder activating the output path groups in the activation order of the second mode.
The selecting of the one of the plurality of driving modes selects one of the driving modes in response to a mode select signal that is provided by an external control unit to the display driver IC or applied to the display driving IC by making voltages of input pads of the display driver IC different.
The display driving method further comprises simultaneously scanning the column data to the column lines.
The present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
a illustrates a sequential driving mode in a conventional display driver IC;
b is a table representing an order of output pads of the conventional display driver IC, which are activated according to the sequential driving mode of
a illustrates a zigzag driving mode in a conventional display driver IC;
b is a table representing an order of output pads of the conventional display driver IC, which are activated according to the zigzag driving mode of
The present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as being limited to embodiments set forth herein; rather, embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the art. Throughout the drawings, like reference numerals refer to like elements.
a illustrates a sequential driving mode in a display driver IC 100a, and
Referring to
Assume that 44 row line groups RLiG (i is a natural number corresponding to 132 or less) that are obtained by dividing the 132 row lines into groups of 3 adjacent row lines are numbered from the top of the panel 200. Row data groups RDiG are scanned to corresponding row line groups RLiG through corresponding row output pad groups OPiG. The display driver IC 100a activates one of the row output pad groups OPiG to scan the row data group corresponding thereto for each row scan clock pulse.
Column output pads B outputting column data CTDA are located at the center of one side of the display driver IC 100a and row output pads A1 and A2 outputting the row data RDiG are respectively located at both sides of the column output pads B. The row output pads A1 (referred to as “right pads” hereinafter) placed at the right of the column output pads B include first through twenty-second row output pads OP1G through OP22G outputting the first through twenty-second row data groups RD1G through RD22G. The row output pads A2 (referred to as “left pads” hereinafter) placed at the left of the column output pads B include twenty-third through forty-fourth row output pads OP23G through OP44G outputting the twenty-third through forty-fourth row data groups RD23G through RD44G.
The display driver IC 100a sequentially outputs the row data groups RDiG as shown in
a illustrates a zigzag driving mode in a conventional display driver IC 100b, and
Row data are sequentially scanned from the first row line. The display driver IC 110b alternately activates the right pads A1 and the left pads A2, as illustrated in
However, the display driver IC 100a of
The display driver IC 100b of
The input unit 110 receives digital video data IDTA to be displayed on a panel 200. The digital-analog converter 120 converts the digital video data IDTA to analog row data RDTA and analog column data CDTA to be respectively scanned to row lines and column lines of the panel 200.
For purposes of describing an exemplary display driver IC 100, assume that the display driver IC 100 is a display driver IC for driving a super twisted nematic (STN) panel including 132 row lines and that groups of three row data respectively corresponding to three adjacent row lines of the 132 (3n, n is a multiple of 2) row lines include first through nth row data groups RDiG (i is a natural number corresponding to 44 or less). The row data output unit 130 outputs at least one of the first through nth row data groups RDiG for each row scan clock pulse. The row data output unit 130 activates output paths outputting the row data RDTA to the row lines in an activation order of a driving mode that is selected from a plurality of driving modes having different orders of activating the output paths in response to a mode select signal XMODE. When the output paths outputting the first through nth row data groups RDiG to the row lines include first through nth output path groups, the row data output unit 130 activates at least one of the first through nth output path groups for each row scan clock pulse.
The plurality of driving modes can include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activates output path groups of a first output part and output path groups of a second output part when the first output part includes the first through (n/2)th output path groups and the second output part includes the {(n/2)+1}th through nth output path groups. For example, when n is 44, the first mode sequentially activates the first through forty-fourth output path groups and the second mode alternately activates the first output part including the first through twenty-second output path groups and the second output part including the twenty-third through forty-fourth output path groups.
For example, the second mode activates the first output path group of the first output part and then activates the twenty-third output path group of the second output part. Subsequently, the second mode activates the second output path group of the first output part and then activates the twenty-fourth output path group of the second output part. In this manner, the second mode alternately activates the output path groups of the first and second output parts and then activates the twenty-second output path group of the first output part and then the forty-fourth output path group of the second output part. The row data output unit 130 repeats the activation of the first through forty-fourth output path groups in the activation order of the first or second mode.
Referring to
While the output path groups include output lines and output pads outputting the row data groups RDiG, the output path groups are denoted by optiG representing the output pads in
The plurality of counters 131 and 132 respectively output activation orders of driving modes corresponding thereto. The counters 131 and 132 include a first counter 131 outputting the activation order of the first mode and a second counter 132 outputting the activation order of the second mode.
One of the first and second counters 131 and 132 is selected in response to the mode select signal XMODE. For example, the first counter 131 corresponding to the first mode is selected when the mode select signal XMODE is at a logic low level (“L”) and the second counter 132 corresponding to the second mode is selected when the mode select signal XMODE is at a logic high level (“H”).
Accordingly, when n is 44, the first counter 131 sequentially outputs 1, 2, 3, . . . , 43 and 44 and the second counter 132 sequentially outputs 1, 23, 2, 24, . . . , 22 and 44. Here, the counters 131 and 132 can represent the activation orders as 6-bit digital signals.
The decoder 133 activates the output path groups optiG in the activation order ENORD1 or ENORD2 output from the counter selected from the first and second counters 131 and 132. Specifically, the decoder 133 activates the output path groups optiG in the activation order ENORD1 of the first mode when the first counter 131 is selected and activates the output path groups optiG in the activation order ENORD2 of the second mode when the second counter 132 is selected.
The mode select signal XMODE at a logic low level (“L”) is applied to the row data output unit 130a such that the first counter 131 sequentially outputs 1, 2, 3, . . . , 43 and 44 and the decoder 133 sequentially activates the first through nth output path groups optiG in the first mode. The mode select signal XMODE at a logic high level (“H”) is applied to the row data output unit 130a such that the second counter 132 sequentially outputs 1, 23, 2, 24, . . . 22 and 44 and the decoder 133 alternately activates the output path groups optiG of the first and second output parts OUT1 and OUT2 in the second mode.
Referring to
When n is 44, the counter 135 repeatedly outputs numbers 1 through 4. The plurality of decoders 136 and 137 activates output path groups optiG in the activation orders of driving modes corresponding thereto among the plurality of driving modes. The plurality of decoders 136 and 137 include a first decoder 136 that activates the output path groups optiG in the activation order of the first mode and a second decoder 137 that activates the output path groups optiG in the activation order of the second mode. The first decoder 136 corresponds to the first mode and the second decoder 137 corresponds to the second mode.
One of the first and second decoders 136 and 137 is selected in response to a mode select signal XMODE. The first decoder 136 activates output path groups optiG having the same numbers as the numbers ENORD output from the counter 135. The first decoder 136 sequentially activates first through forty-fourth output path groups optiG.
The second decoder 137 matches the numbers ENORD output from the counter 135 to the activation order of the second mode to activate output path groups optiG corresponding to the numbers ENORD. The second decoder 137 activates the first output path group opt1G when the counter 135 outputs “1”, activates the twenty-third output path group opt23G when the counter 135 outputs “2”, and activates the second output path group opt2G when the counter 135 outputs “3” In this manner, the second decoder 137 activates the output path groups optiG corresponding to “4” through “44” output from the counter 135.
The mode select signal XMODE at a logic low level (“L”) is applied to the row data output unit 130b and the first decoder 136 sequentially activates the first through nth output path groups optiG in the first mode. The mode select signal XMODE at a logic high level (“H”) is applied to the row data output unit 130b and the second decoder 137 alternately activates the output path groups optiG of the first and second output parts OUT1 and OUT2 in the second mode.
Referring to
The input unit 110 includes a plurality of pads (not shown) for receiving the video data IDTA and the control signal XCON. The control signal XCON is applied to the display driver IC 100 by making voltages of pads receiving the control signal XCON different. When the plurality of driving modes include the first and second modes, the control signal XCON can have a logic low level (“L”) or a logic high level (“H”) by applying a power supply voltage VDD and a ground voltage GND to the pads.
The mode select signal XMODE can have the same logic level as the control signal XCON. The first mode may be selected by applying the ground voltage GND to the pads and the second mode may be selected by applying the power supply voltage VDD to the pads. The control signal XCON can be provided by an external control unit (not shown).
The display driver IC 100 further includes a column data output unit 150 for simultaneously outputting the column data CDTA to the column lines.
At least one of first through nth output path groups is activated for each row scan clock pulse at block S740. For purposes of the description, assume groups of three row data respectively corresponding to adjacent three row lines of 3n (n is a multiple of 2) row lines and include first through nth output path groups, the first through nth output path groups corresponding to output paths for outputting the first through nth row data groups to the row lines.
A plurality of counters output the activation orders of driving modes corresponding thereto among the plurality of driving modes. The output paths at activated at block S740 in the activation order output from a counter corresponding to the selected driving mode among the plurality of counters.
The plurality of driving modes include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activates first output part including the first through (n/2)th output path groups and the second output part including the {(n/2)+1}th through nth output path groups.
The plurality of counters include a first counter outputting the activation order of the first mode and a second counter outputting the activation order of the second mode.
A plurality of decoders activate the output path groups in the activation orders of driving modes corresponding thereto among the plurality of driving modes. The output paths are activated at block S740 by a decoder corresponding to the selected driving mode among the plurality of decoders.
The plurality of driving modes include first and second modes. The first mode sequentially activates the first through nth output path groups. The second mode alternately activates first output part including the first through (n/2)th output path groups and the second output part including the {(n/2)+1}th through nth output path groups.
The plurality of decoders include a first decoder activating the output path groups in the activation order of the first mode and a second decoder activating the output path groups in the activation order of the second mode.
One of the driving modes is selected at block S730 in response to a mode select signal. The mode select signal is provided by an external control unit to the display driver IC or applied to the display driving IC by making voltages of input pads of the display driver IC different.
The display driving method 700 further includes simultaneously scanning the column data to the column lines at block S760.
The display driving method for supporting various driving modes according to an embodiment of the present invention has the same technical spirit as that of the above-described display driver IC. Accordingly, those skilled in the art can understand the display driving method from the explanation of the aforementioned display driver IC so that detailed explanation thereof is omitted.
As described above, the display driver IC and display driving method according to an embodiment of the present invention can support various driving modes at the request of a user without needing a new chip design.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2006-0004443 | Jan 2006 | KR | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5136282 | Inaba et al. | Aug 1992 | A |
| 5376944 | Mogi et al. | Dec 1994 | A |
| 5726677 | Imamura | Mar 1998 | A |
| 5945974 | Sharma et al. | Aug 1999 | A |
| 7023419 | Park | Apr 2006 | B2 |
| 7298354 | Yang | Nov 2007 | B2 |
| Number | Date | Country |
|---|---|---|
| 07-175451 | Jul 1995 | JP |
| 09-006278 | Jan 1997 | JP |
| 09-330054 | Dec 1997 | JP |
| 1020000021177 | Apr 2000 | KR |
| Number | Date | Country | |
|---|---|---|---|
| 20070165014 A1 | Jul 2007 | US |
