KR20000066456A - apparatus and method for data driving to use masking - Google Patents

Abstract

PURPOSE: A device and method for driving data using the masking is provided to reduce a chip area, and emphasizes some part of either a specific line or data in a flat panel display. CONSTITUTION: The data driving device includes a reference signal part(10). a controller(20) and a display part(30). The reference signal part(10) outputs a duty ratio of a scan signal and image data to be displayed after receiving external image signal. The controller converts a duty ratio generated from the reference signal part, makes a residual scan time, and converts a data by using a masking. The display part receives the converted duty ratio and the converted image data from the controller, and displays them on the panel. Thereby, the data driving device reduces a chip area, and emphasizes some part of either a specific line or data in a flat panel display.

Description

Apparatus and method for data driving to use masking}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display device, and more particularly, to a data driving apparatus using masking to reduce the area of a chip and to emphasize the brightness of a specific line or part of data in data display of a flat panel display without additional power consumption. And to a method.

Currently, various display devices are used in various fields, ranging from small size TVs to large screens, starting with a CRT (Cathode Ray Tube).

As a result of the development of electronic technology, according to the trend of miniaturization, light weight, and low voltage of various electronic devices, a new flat panel display device having thin, light, low power consumption characteristics has been developed.

These new forms of flat panel displays are voltage-driven, such as Liquid Crystal Display (LCD), Plasma Display Panel (PDP), Visual Fluorescent Display (VFD), Field Emission Display (FED), Light Emitting Diode (LED), and EL (EL). Current-driven displays such as electroluminescence.

Hereinafter, a flat panel display driving circuit according to the related art will be described with reference to the accompanying drawings.

1 is a diagram illustrating a driving circuit diagram of a flat panel display according to the related art. The system interface unit 1 converts externally input control signals or data into control signals required for display, and the system interface unit 1 converts them. In the memory unit 2, the data value corresponding to the control signal is stored, the data drive circuit unit 3 for applying the output data of the memory unit 2 to a plurality of data lines, and the system interface unit 1 A control circuit section 4 for determining the same duty ratio according to the converted control signal and a scan drive circuit section 5 for applying signals according to the duty ratio determined in the control circuit section 4 to a plurality of scan lines. It is composed.

The plurality of scan lines and the plurality of data lines intersect each other, and display and display data on pixels of dots that cross each other.

FIG. 2 is a timing chart of a flat panel display according to the related art. Referring to FIG. 2, when each scan line is selected, data is turned on / off for each dot by selecting a data line at a desired position for data display. (on / off)

That is, when the first scan line is on time, data may be displayed at a desired position by turning on a data line for displaying data among the plurality of data lines until the first scan line is turned off.

In this case, the brightness of the displayed pixel is proportional to the time when each scan line is turned on and the time when the data line is turned on.

And the time that the scan line is on (on) has a duty ratio (duty ratio) as shown in FIG. When set to, the time for driving each scan line is one frame time when T _F Becomes

As shown in FIG. 2, when all the on-times of the data lines are driven the same, all pixels of the panel have the same brightness.

In addition, when a user wants to display a specific part of the panel brighter for efficient data retrieval to an icon line or data retrieval of a portable terminal, a method of applying high voltage or high current to a desired data line through switching is used. do.

Another method is to adjust the on time of the data line.

4 is a data driving circuit diagram of a flat panel display according to the prior art, where (a) is a circuit diagram of a current drive type and (b) is a circuit diagram of a voltage drive type.

Referring to FIG. 4, a high-voltage or high current is connected to a data line to be displayed brighter by a switch at a high high voltage or high current, and a high-voltage or high current is applied to a specific line to be displayed brighter through the data drive 6. 7) is displayed.

However, the brightness control method of the flat panel display device according to the related art requires an additional circuit to be applied to the data line to apply a high voltage or a high current, respectively, thereby increasing the chip area and in the case of the voltage driven type. A stable voltage must be maintained at all times, and in the case of a current driven type, there is a difficulty in considering a current matching problem of each current source.

In addition, in order to adjust the on time of each data line, a pulse width modulation (PWM) control circuit must be installed in the data line, thereby causing a problem of large chip area.

Therefore, the present invention is to solve the above problems, masking to minimize the chip area by eliminating additional elements of the circuit, and to efficiently control the brightness of the desired portion without a separate power consumption using only the digital signal It is an object of the present invention to provide a data driving apparatus and method using

1 is a driving circuit diagram of a flat panel display according to the prior art;

2 is a flat panel display timing diagram according to the prior art;

3 shows the duty ratio according to the prior art. Scan line drive timing chart

Figure 4 (a) is a circuit diagram of the current driven type of a flat panel display according to the prior art

(b) is a circuit diagram of a voltage driven type of a flat panel display according to the prior art

5 is a flat panel display driving circuit diagram according to the present invention;

6 is a block diagram of a control unit according to the present invention;

7 shows the duty ratio according to the present invention. Scan line drive timing chart

FIG. 8 is a timing diagram in which 40 scan lines are driven in FIG. 7 and the remaining scan time is additionally applied to an arbitrary scan line.

9 is a configuration diagram when additionally driving a scan line according to the present invention;

10 is a schematic diagram using data masking according to the present invention;

11 is a timing diagram illustrating waveforms driving the operation of FIG. 10.

* Explanation of symbols for main parts of the drawings

1, 11: system interface 2, 12: control circuit

3, 13: memory section 4, 32: data drive circuit section

5, 31: scan drive circuit portion 6: data drive

7: display panel 10: reference signal unit

20: control unit 21: scan control unit

22: data controller 23: frequency converter

24: frequency selection unit 25: display control unit

26: duty ratio control unit 27: scan signal control unit

28: data signal controller 30: display unit

A feature of a data driving apparatus using masking according to the present invention for achieving the above object is a reference signal unit for outputting the image data to be displayed and the duty ratio of the scan signal to the external image signal input; A control unit for converting a duty ratio output from the reference signal unit to create an extra scan time and converting data using masking, and receiving the converted duty ratio and image data from the control unit It is configured to include a display unit to display on the panel.

The control unit may further include: a scan control unit for converting a duty ratio and applying an extra scan time to a scan line to convert the scan time for driving a scan for one frame time to display brightly; and the additionally applied scan line. And a data controller for masking all or part of the data corresponding to the data.

A feature of the data driving method using masking according to the present invention for achieving the above object is the surplus time (extra scan time) by adjusting the duty ratio of the scan time while maintaining the same frame frequency Creating each step; displaying each scan line sequentially; additionally driving each scan line to display brighter with the surplus time; displaying only the driving data of the plurality of data lines to display brighter and remaining The driving data of the data line is masked to control the brightness of each data line to be displayed brighter.

A characteristic of a data driving method using masking according to the present invention for achieving the above object is to mask data of a specific data line to be displayed brighter by adjusting brightness of a specific data line. To adjust the brightness of the data.

A feature of the data driving method using masking according to the present invention for achieving the above object is to mask the data and the excess scan time of the data line to be displayed brighter by adjusting the brightness of the specific data line (masking) to adjust the brightness of the data.

Hereinafter, a preferred embodiment of a data driving apparatus and method using masking according to the present invention will be described with reference to the accompanying drawings.

5 is a flat panel display driving circuit diagram according to the present invention. First, the reference signal unit 10 includes a system interface unit 11 for converting a control signal or data input from the outside into a control signal for display, and the system interface unit. The control circuit 12 determines the same duty ratio according to the control signal converted in (11), and the memory unit 13 in which data corresponding to the control signal converted in the system interface unit 11 is stored. It is composed.

In addition, the control unit 20 includes a data control unit 22 for masking a duty ratio determined by the control circuit unit 12 and output data of the memory 13, and a control unit 12 determined by the control circuit unit 12. While maintaining the same frame frequency as the signal according to the duty ratio (duty ratio) while converting the duty ratio (duty ratio) to create a free scan drive time, the scan control unit 21 for adding the free scan drive time to a specific line It is composed.

The display unit 30 scans the data drive circuit unit 32 for applying the output data of the data control unit 22 to each data line and the driving signal of the scan control unit 21 to display the scan line. The drive circuit part 31 is comprised.

6 is a block diagram of a control unit according to the present invention, wherein the control unit 20 receives a main clock output from the control circuit unit 12 and generates a plurality of clocks required for converting a duty ratio. A frequency converter 23, a frequency selector 24 for selecting one of the generated clocks as a reference clock, a duty ratio controller 26 for setting a duty ratio with the selected reference clock, and the set A scan signal controller 27 for generating a signal for driving a scan line at a duty ratio, a data signal controller 28 for converting corresponding data when an excess scan time is applied to a specific scan line, and the duty ratio controller 26 And a display control unit 25 for synchronizing the scan signal control unit 27 and the data signal control unit 28 with each other.

The scan control unit 21 configured as described above converts the duty ratio to increase the number of pulses capable of driving the scan for one frame time, thereby creating a free scan driving time and displaying each scan line brightly. In addition to, it drives brighter than other scan lines.

The data controller 22 drives all of the data of the driven lines when the remaining scan driving time is applied to a specific scan line by using the converted duty ratio which is the output of the scan controller 21. Alternatively, only a part of data of a line to be driven is selected and the rest is masked to drive.

At this time, in order to convert the duty ratio while maintaining the same frame frequency, it is necessary to convert the frequency required for timing control. The necessary control clock f _control is calculated as follows.

f _control = (the number of clocks required to display one scan line) * (number of frames) * (duty ratio) ^-1

As an example, referring to FIG. 3, the frame frequency is 70 Hz and the duty ratio is In this case, if 100 clocks are required to display data of one scan line, the control clock f ₄₀ is calculated as follows.

f ₄₀ = 100 * 40 * 70 = 280 kHz

At this time, while maintaining the same frame frequency as shown in FIG. The control clock f ₄₈ is converted as follows.

f ₄₈ = 100 * 48 * 70 = 336 kHz

In FIG. 6, the frequency converter 23 generates a clock required when the duty ratio is converted, as in the embodiment.

The clock generated by the frequency converter 23 is selected as a control clock by the frequency selector 24 when a duty ratio is set and used as a reference clock in the entire timing circuit.

As such, the control signal input through the system interface unit 11 converts the number of pulses capable of driving the scan for one frame time according to a signal for setting a duty ratio.

The scan signal controller 27 finally generates a signal for driving the scan line using the converted scan driving pulse.

The data signal controller 28 selects data to be displayed on the selected scan line and turns on / off the data signal. The data signal controller 28 applies only a part of the data when the scan time remaining after driving the scan line is additionally applied to the specific scan line. It masks the data that is not needed, leaving emphasis on specific parts.

7 shows the duty ratio according to the present invention. 8 is a timing diagram of driving 40 scan lines and applying the remaining scan time to an arbitrary scan line in FIG. 7.

7 shows the duty ratio When the frame time is converted to T _F , the scan time allocated to each scan line is Drive 40 scan lines and the remaining scan time (surplus time, T _R ) Becomes

In addition, when the surplus time T _R is additionally applied to the scan lines 1 to 8 as shown in FIG. 8, the scan driving time of the scan lines 1 to 8 is Becomes

Therefore, it has twice the driving time of other scan lines.

In this case, if the data signal applied to the redundant scan lines 1 to 8 is applied without masking, the result as shown in FIG. 9 is obtained.

As described above, since the results shown in FIG. 9 are controlled in units of scan lines, the above method is not suitable when only some data of the data lines are to be displayed brightly.

That is, in the exemplary embodiment, if only “L” characters are to be displayed brightly in the “LG” data brightly displayed in FIG. 9, it is impossible to implement them because they are displayed in scan line units.

As such, in order to emphasize the data of some of the data lines, the data line control method should be used in addition to the scan line control method.

A masking method will be used as the data line control method.

The masking method further drives specific scan lines as shown in FIG. 8 while leaving the data of the data lines to be brightly displayed among the plurality of data lines as it is, and masking and deleting the data of the remaining data lines. The data will not be displayed brightly.

Therefore, the scan lines 1 to 40 perform the same operation as the driving of a general flat panel display, and the scan lines 41 to 48 are used for the data of the portion desired to be displayed brightly, and the data can be partially displayed brightly using masking.

FIG. 10 is a configuration diagram displayed using data masking according to the present invention, and FIG. 11 is a timing diagram illustrating waveforms driving the operation of FIG. 10.

Referring to FIG. 11, each pixel has the same driving time for one frame time T _F except the surplus scan time T _R , thereby showing the same brightness.

During the redundant scan time (T _R ), only one to six of the data lines are driven while the redundant scan lines 1 to 8 are driven, so that one to six characters in the data line are twice as large as other characters in one frame. You have a run time.

Thus, as shown in FIG. 10, only the letters “L” in the data lines 1 to 6 of the characters of the 12 data lines are displayed brighter than other characters.

The driving time of the additionally driven scan line may be converted in steps, and may be additionally driven in a plurality of desired scan lines.

In addition, in the case of the data line, the masking time T _M may be converted in stages, and the data of a plurality of desired data lines may be masked.

In this way, the scan control unit 21 adjusts the surplus time T _R to adjust the scan line for which brightness is to be adjusted, and the data control unit 22 selectively controls only data of the data line for which brightness is to be adjusted, thereby preventing unnecessary data. By masking, data at any position of the data display panel can be adjusted in brightness.

In addition, as the duty ratio increases, the time to drive each scan line is relatively reduced, but each scan line driving time by adjusting the duty ratio is reduced as a whole, and the time to decrease is reduced. It is very small compared to the line driving time, so it does not affect the overall data display.

As described above, the data driving apparatus and method using masking according to the present invention change the data brightness of a specific part of data displayed on a specific line or panel when displaying data on the display device. Since it can be displayed by the user, it is effective to enable efficient data transfer to the user.

In addition, by applying to a variety of flat panel displays, including a portable terminal there is an effect that can display the data of a specific portion more clearly without a separate power consumption.

In addition, there is a big advantage in terms of utilization of chip area because the digital circuit can be implemented only without configuring an additional circuit inside the chip to adjust the brightness of data at a specific position.

Claims (6)

A reference signal unit for outputting the duty ratio of the scan signal and the video data to be displayed by inputting an external video signal; A control unit for converting a duty ratio output from the reference signal unit to create an extra scan time and converting data using masking; And a display unit configured to receive the duty ratio and image data converted by the control unit and display the image data on the panel. The method of claim 1, The control unit may include: a scan control unit for converting a duty ratio and converting a scan time capable of driving a scan for one frame time to additionally apply an extra scan time to a scan line to be displayed brightly; And a data controller for driving all or part of data corresponding to the additionally applied scan line and masking the remaining data. The method of claim 1, The control unit includes a frequency converter for generating a plurality of clocks required to convert the duty ratio; A frequency selector for selecting one of the generated clocks as a reference clock; A duty ratio controller configured to set a duty ratio to the selected reference clock; A scan signal controller configured to generate a signal for driving a scan line at the set duty ratio; A data signal controller for converting the corresponding data when the excess scan time is applied to a specific scan line; And a display controller for synchronizing the duty ratio controller, the scan signal controller, and the data signal controller. Creating a surplus time by adjusting the duty ratio of the scan time while maintaining the same frame frequency, Additionally driving each scan line to display brighter with the surplus time; Masking drive data of the plurality of data lines to be displayed brighter and masking the drive data of the remaining data lines, thereby controlling the brightness of each data line to be displayed brighter. Apparatus and method for driving data using masking. The method of claim 4, wherein The adjusting of the brightness of the specific data line may include masking the data of the specific data line to be displayed brighter to adjust the brightness of the data. The method of claim 4, wherein The adjusting of the brightness of the specific data line may include controlling the brightness of the data by masking the data and the excess scan time of the data line to be displayed brighter and controlling the brightness of the data. .