JP2939516B2 - Driving method of ferroelectric liquid crystal panel - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for driving a ferroelectric liquid crystal panel using a TN type liquid crystal panel drive IC.

[Prior Art] In recent years, ferroelectric liquid crystals have been actively studied.
However, the operation mode is significantly different from the conventional TN type liquid crystal. Therefore, a liquid crystal driving LSI currently used for driving a TN type liquid crystal panel cannot be used as it is for driving a ferroelectric liquid crystal panel.

Therefore, a new drive circuit was developed for a ferroelectric liquid crystal panel (for example, Japanese Patent Laid-Open No. 62-87941), or an LSI for driving a TN type liquid crystal panel was used as an analog multiplexer to generate other functions. ON waveform created by the vessel, OFF
Distribute the waveform to the drive electrode (J.Phys.E: Sci.Instrum. 2
1 (1988) 460-466).

However, in the former case, if the drive circuit is configured using the current IC, the circuit becomes huge and impractical as the number of drive electrodes on the panel increases, and if a new LSI is manufactured, There was a problem that the cost was high.

Also, in the latter case, there is a problem that a function generator for generating the ON waveform and the OFF waveform is required, and a complicated circuit is required to synchronize with the driving LSI.

In view of such problems, the applicant of the present application
1-56298 proposes a method for driving a ferroelectric liquid crystal panel using a currently available TN type liquid crystal panel driving LSI.

[Problems to be Explained by the Invention] The driving method of Japanese Patent Application No. 1-56298 described above is excellent in that a ferroelectric liquid crystal panel is driven by using a TN type liquid crystal panel driving LSI. However, in this driving method, correspondence between data to be displayed and an LSI control signal is not so good, and there is room for improvement in simplifying a control procedure.

The present invention has been made in view of such circumstances, and a simple driving circuit using a currently available TN-type liquid crystal panel driving LSI, and driving a ferroelectric liquid crystal panel by a simple control procedure. It is an object of the present invention to provide a driving method that is enabled.

[Means for Solving the Problems] To achieve the above object, a method of driving a ferroelectric liquid crystal panel of the present invention is as follows.

That is, in the method according to the first aspect, when D = 1 and the dot is
One of the four input terminals is selected in accordance with a combination of display data D indicating that the dot is OFF when D = 0, and two digital control signals of the liquid crystal drive output AC signal M. A liquid crystal drive IC that outputs the voltage input to the output terminal to drive the segment side of the ferroelectric liquid crystal panel is used. Further, D = 1 selects a scanning line, and D = 0 selects a scanning line. One of the four input terminals is selected in accordance with a combination of two digital control signals of the display data D indicating non-selection and the liquid crystal drive output alternating signal M, and the voltage input to the input terminal is output to the output terminal. A method of driving a ferroelectric liquid crystal panel using a liquid crystal driving IC that outputs and drives a common side of the ferroelectric liquid crystal panel, wherein the liquid crystal driving is performed when the display data D is D = 1. Output AC 1,0,0 at a time adjacent to each of the signal M,
By changing to 1, writing and erasing of desired dots are continuously performed, and when the display data D is D = 1, the liquid crystal driving output AC conversion signal M is changed to 0, 1, 1,. When the display data D is D = 0, the liquid crystal drive output AC conversion signal M is changed from 0 to 1 or from 1 to 0 at the adjacent time when the display data D is D = 0. The state of the dot is not changed even if it is changed to.

Further, in the method according to claim 4, the dot is ON when D = 1,
Display data D indicating that the dot is OFF when D = 0
And one of the four input terminals is selected in accordance with a combination of the two digital control signals of the liquid crystal drive output alternating signal M, and the voltage input to the input terminal is output to the output terminal to output the ferroelectric liquid crystal. A liquid crystal driving IC for driving the segment side of the panel is used. Further, display data D representing selection of a scanning line when D = 1, non-selection of a scanning line when D = 0, and a liquid crystal driving output AC signal M
LCD drive that selects one of the four input terminals according to the combination of the two digital control signals and outputs the voltage input to the input terminal to the output terminal to drive the common side of the ferroelectric liquid crystal panel A ferroelectric liquid crystal panel using an IC for driving, wherein when the display data D is D = 1, the liquid crystal drive output AC signal M is set to 1, 0,
By changing to 0 and 1, writing and erasing of desired dots are continuously performed, and when the display data D is D = 1,
By changing the liquid crystal drive output AC signal M to 0, 1, 1, 0 at adjacent times, desired dots are continuously erased and written, and the display data D becomes D = 0.
In this case, the state of the dot remains unchanged even if the liquid crystal drive output AC signal M is changed from 0 to 1 or from 1 to 0 at adjacent times.

 Hereinafter, the solution will be specifically described.

As shown in FIG. 1, a driving device for implementing the present driving method includes a ferroelectric liquid crystal panel 1, a driving IC 2 for driving the panel 1, and a controller 3.

The ferroelectric liquid crystal panel 1 is in a bistable state and has a clear threshold characteristic.

That is, when the applied voltage pulse has a certain pulse width τ and a positive voltage pulse of a certain threshold Vth (> 0) or more is applied, writing is performed and the display is turned on (lit state), When a negative voltage pulse of −Vth or less is applied, erasing is performed and the display is turned off (turned off). The display state does not change with a voltage pulse whose absolute value is Vth or less, and the current display is maintained. is there.

The common and segment driving ICs 2 have display data D,
LCD drive output AC signal M and LCD drive voltage are input,
A liquid crystal drive output is output (see FIG. 2).

Here, when the IC drives the segment side (segment driver mode), the liquid crystal driving IC normally drives a plurality of segment electrodes of the liquid crystal panel simultaneously. The display data D corresponding to each of the plurality of electrodes is serially transferred to the driving IC (sometimes transferred in parallel to improve the transfer speed), and is internally latched to control the output. When used for a TN liquid crystal panel, D = 1 and 0 indicate ON of the dot on the corresponding segment electrode (lighting state),
Indicates OFF (lights out).

When the IC drives the common side (common driver mode), the display data D = 1 and 0 correspond to selection and non-selection of the corresponding common electrode, respectively.

In both the segment driver mode and the common driver mode, the liquid crystal drive output AC signal M
When used for a TN liquid crystal panel, M = 1,0,1,0... In a time series to switch the output voltage between positive and negative to make it AC, and to set the DC component of the voltage applied to the liquid crystal to 0. Suppresses chemical degradation of liquid crystal. M, unlike D, has no latching mechanism and is common to all outputs.

Further, the liquid crystal driving voltage is input to the input terminal V ₁ ~V _4, when used as a TN liquid crystal panel, typically, V _1> V ₃
Set the voltage as> V ₄ > V ₂ .

On the other hand, the output terminal Y (Y ₁ ~Yn) of the liquid crystal drive output is a plurality, for driving a plurality of electrodes of the common side and the segment side of the liquid crystal panel at the same time.

Next, the display data D, a liquid crystal drive output alternating signal M, the relationship between the input terminals V ₁ ~V ₄ and the output Y is selected.

There are four combinations of the display data D and the digital control signal of the liquid crystal drive output alternating signal M, and _{one of the} four input terminals V ₁ , V ₂ , V ₃ , V ₄ is selected according to each combination, The voltage applied to the selected input terminal appears at the output terminal Y. In the segment driver mode, the input terminal V ₁ when (D, M) = (1, 1), the input terminal V ₂ when = (1, 0), and the input terminal V when = (0, 1). ₃ , input terminal V ₄ when = (0,0); in common driver mode, input terminal V ₂ when (D, M) = (1,1); input terminal V ₁ when = (1,0) , = (0,1) is the input terminal V ₃ , and == (0,0) is the input terminal V ₄ .

Usually, the use as a TN liquid crystal panel, the segment driver mode, four-level position voltage _{vsh +, vsh -, vsl +} , vsl - (vsh +> vsl +> vsl -> vsh -) to V ₁ = _{vsh +, V 2 = vsh -} , V 3 = vsl +, V 4 = vsl - giving as in (FIG. 3 (a)).

Further, in the common driver mode, four-level position voltage _{vch +, vch -, vcl +} , vcl - (vch +> vcl +> vcl -> vch -) to _{V 1 = vch +, V 2} = vch -, _{V 3 = Vc 1+, V 4} = vcl - giving as in (FIG. 3 (b)).

However, in the _{overall, vsh + = vch +> vcl} +> vsl +> vsl ->
vcl _-> vch _- = vsh _- to the relationship.

As a method of driving the above-described ferroelectric liquid crystal panel 1 by the driving IC 2, there is the following method.

In the driving method 1 segment driver mode, the liquid crystal driving voltage of the three-level position _{vs +, vo, vs - (} vs +>vo> vs -) to _{V 1 = vs +, V 2} = vs -, V 3 = V 4 = vo, like assigned by driving the segment side of the ferroelectric liquid crystal panel (Fig. 4 (a)), the liquid crystal driving voltage of two levels position in the common driver mode _{vc +, vc - (vc +} > vc -) the _{V 1 = V 3 = vo +} , V 2 = V 4 = vo -, allocated to drive the common side of the ferroelectric liquid crystal panel as shown in (FIG. 4 (b)).

However, in the _{whole, vs +> vc +> vo} > vc -> vs - in the relationship.

The voltage is set in this way, and the display data D
After the liquid crystal drive output AC signal M is changed from 1 to 0 after the determination of, the output changes as shown in FIG. 5 (a), and the liquid crystal applied voltage changes accordingly.

Here, the segment electrode is ON with the common electrode selected.
In the state, a large positive voltage is applied to the liquid crystal at M = 1 (the direction from the segment electrode to the common electrode is positive), and a large negative electrode at M = 0 (the absolute value is vth
Above), and the display on the ferroelectric liquid crystal panel is erased.

When the common electrode is not selected or the segment electrode is off, a small voltage is applied to the liquid crystal (absolute value is less than vth)
, The display state of the ferroelectric liquid crystal panel does not change. That is, by changing the liquid crystal drive output AC signal M from 1 to 0, a desired dot (a dot of D = 1 on the segment electrode) can be erased.

In any case, when the liquid crystal drive output AC signal M is changed from 1 to 0, a positive / negative symmetric voltage is applied to the liquid crystal, so that the net DC voltage component is averaged to 0 and the deterioration of the liquid crystal can be prevented. .

Conversely, when the liquid crystal drive output AC signal M is changed from 0 to 1, the liquid crystal applied voltage changes as shown in FIG. 5 (b).

Here, the segment electrode is ON with the common electrode selected.
In the state (1), a large negative voltage is applied to the liquid crystal when M = 0, and a large positive voltage (absolute value is not less than vth) is applied when M = 1, and writing to the ferroelectric liquid crystal panel occurs.

When the common electrode is not selected or the segment electrode is OFF, only a small voltage is applied to the liquid crystal, so that the display state of the ferroelectric liquid crystal panel does not change. That is, by changing the liquid crystal drive output AC signal M from 0 to 1, a desired dot (a dot of D = 1 on the segment electrode) can be written.

When the liquid crystal driving output AC signal M is changed from 0 to 1, a positive / negative symmetric voltage is applied to the liquid crystal, so that the net DC voltage component is averaged to 0, thereby preventing the deterioration of the liquid crystal.

When the liquid crystal drive output AC signal M is changed to 1, 0, 0, 1, it is possible to continuously erase and write desired dots.

By changing the liquid crystal drive output AC signal M to 0, 1, 1, 0, writing and erasing of desired dots can be performed continuously.

In this method, only the dots to be turned off can be erased in the erasing process, so that there is no problem even if the writing process comes before the erasing process.

In the driving method 2 segment driver mode, the liquid crystal driving voltage of the three-level position _{vs +, vo, vs - (} vs +>vo> s -) to _{V 1 = vs -, V 2} = vs +, V 3 = V 4 = assigned as vo drives a segment side of the ferroelectric liquid crystal panel (FIG. 6 (a)), the common driver mode, the liquid crystal driving voltage of two levels position _{vc +, vc - (vc +} > vc -) Are assigned as V ₁ = V ₃ = vc ₋ and V ₂ = V ₄ = vc ₊ to drive the common side of the ferroelectric liquid crystal panel (FIG. 6 (b)).

However, in the whole, vs +> vc +> vo >vc-> vs - in the relationship.

Here, based on the same concept as in driving method 1, the seventh
As shown in the figure, when the liquid crystal drive output AC signal M is changed from 1 to 0, a desired dot can be written (FIG. 7A), and the liquid crystal drive output AC signal M changes from 0 to 1. Then, desired dots can be erased (FIG. 7 (b)).

When the liquid crystal drive output AC signal M is changed to 0, 1, 1, 0, erasing and writing of desired dots can be performed continuously.

By changing the liquid crystal drive output AC signal M to 1, 0, 0, 1, writing and erasing of desired dots can be performed continuously.

In this method, the roles of 0 and 1 of the liquid crystal drive output AC signal M are switched as compared with the driving method 1.

In the driving method 3 segment driver mode, four-level position the liquid crystal driving voltage of _{vsh +, vsh -, vsl +} , vsl - (vsh +> vsl +> vsl -> vsh -) to _{V 1 = vsh +, V 2} = vsh _{-, V 3 = vsl +,} V 4 = vsl -, allocated to drive the segment side of the ferroelectric liquid crystal panel as shown in (FIG. 8 (a)).

The common driver mode, four-level position of the liquid crystal drive voltage _{vch +, vch -, vcl +} , vcl - (vch +> vcl +> vcl -> vch -) to _{V 1 = vcl +, V 2} = vc 1-, _{V 3 = vch +, V 4} = vch - driving a common side of the ferroelectric liquid crystal panel assigned as (Figure 8 (b)).

However, in the _{overall, vsh +> vsl +> vsl} -> vsh -, vch +> v
_{cl +> vcl -> vch -} , vsh +> vch +> vch -> vsh - in the relationship.

Here, based on the same concept as in driving method 1, the ninth
As shown in the figure, when the liquid crystal drive output AC signal M is changed from 1 to 0, a desired dot can be erased (FIG. 9A), and the liquid crystal drive output AC signal M changes from 0 to 1. Then, desired dots can be written (FIG. 9B).

When the liquid crystal drive output AC signal M is changed to 1, 0, 0, 1, it is possible to continuously erase and write desired dots.

By changing the liquid crystal drive output AC signal M to 0, 1, 1, 0, writing and erasing of desired dots can be performed continuously.

In the present method, the same voltage waveform as that actually applied to the liquid crystal is obtained, except for the method of applying the liquid crystal driving voltage as compared with the driving method 1.

The liquid crystal driving voltage of the driving method 4 level position in the fourth segment driver mode _{vsh +, vsh -, vsl +} , vsl - (vsh +> vsl +> vsl -> vsh -) to _{V 1 = vsh -, V 2} = vsh + , V ₃ = vsl ₋ , V ₄ = vsl ₊ to drive the segment side of the ferroelectric liquid crystal panel (FIG. 10 (a)).

The liquid crystal drive voltage of the four-level position in the common driver mode _{vch +, vch -, vcl +} , vcl - (vch +> vcl +> vcl -> vch -) to _{V 1 = vcl -, V 2} = vcl +, V 3 = Vch _- and V ₄ = vch ₊ to drive the common side of the ferroelectric liquid crystal panel (FIG. 10 (b)).

However, in the _{overall, vsh +> vsl +> vsl} -> vsh -, vch -> v
_{cl +> vcl -> vch -} , vsh +> vch +> vch -> vsh - in the relationship.

Here, based on the same idea as in driving method 1, the eleventh
When the liquid crystal drive output AC signal M is changed from 1 to 0 as shown in the figure, a desired dot can be written (FIG. 11A), and the liquid crystal drive output AC signal M is changed from 0 to 1. Then, a desired dot can be erased (FIG. 11 (b)).

When the liquid crystal drive output AC signal M is changed to 0, 1, 1, 0, erasing and writing of desired dots can be performed continuously.

By changing the liquid crystal drive output AC signal M to 1, 0, 0, 1, writing and erasing of desired dots can be performed continuously.

In this method, the roles of 0 and 1 of the liquid crystal drive output AC signal M are switched as compared with the driving method 3.

In any method, the setting of the voltage need not be strict. For example, in driving method 1, V _{3
= V 4 = vo, V 1} = V 3 = vc + at the common _{side, V 2 = V 4 = vc} - is desirably. However, when IC used requires that the _{V 1> V 3> V 4} > V 2, vo the set voltage, vc _+, vc _- slightly offset from, V _3> vo> V ₄ in the segment side, the common By the side
_{V 1> vc +> V 3} , V 4> vc -> Yomoi manner satisfy the relationship of V _2.

However, the difference between V _3, V ₄ and vo of the segment side, V _1, V ₃ and the difference in vc ₊ at the common side, V _2, V ₄ and vc _- difference between the total liquid crystal driving power supply voltage It is desirable to keep it at 10% or less of (vs ₊ −vs ₋ ). If it exceeds 10%, rewriting of the liquid crystal may not be successful.

 The same applies to driving methods 2 to 4.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 12 is an example of a circuit for implementing the liquid crystal panel driving method of the present invention.

In the same figure, 100 is a ferroelectric liquid crystal panel (simple matrix display type), 200 is a common drive IC, 300 is a segment drive IC, 400 is a preprocessing circuit provided before the segment drive IC, and 500 is a drive. A controller (CPU) that sends a control signal to the IC for driving 200, the driving IC 300 and / or the preprocessing circuit 400 via the port 501, and 600 is a liquid crystal driving level circuit.

The preprocessing circuit 400 does not necessarily have to be provided, as will be described in detail later. That is, the output of the port may be directly input to the D terminal of the segment driving IC. In this case, the function of the preprocessing circuit 400 is performed by the controller 500.

Here, the common drive IC 2
00 and the liquid crystal drive voltage is supplied to the segment drive _{IC300 vs +, vc +, vo} , vc -, vs - the power supply voltage _{v L c +, v L c} - (v L c +> v
Make) divides in the resistance _{- L} c. At this time, the driving method is 1/3
To the bias _{method, vs + -vc + = vc +} -vo = vo-vc - = vc - -vs - (> 0) to.

Next, the method of this embodiment will be described with reference to a time chart shown in FIG. Here, first, an example in which the preprocessing circuit is not used will be described.

The segment drive IC is controlled as follows. bitmap data d ₁ to be displayed on the i-th row, d _2, d ₃
When dn (dot light on at dj = 1, light off at dj = 0) is given, first, data obtained by inverting dj 1,0 is given as display data D (i at i in FIG. 13D). This is the inverted data for erasing the line).

CK is a shift clock for serial data transfer. When n pieces of data for one row are transferred into the segment driving IC, the data is latched by lowering the latch clock LC.

Thereafter, when the liquid crystal drive output AC signal M is changed from 1 to 0, the output changes as shown in FIG. Thirteenth
In the time chart shown in the figure, this corresponds to the i-th line erasure output at the segment output YSj.

When D = 1, that is, when dj is 0 (it is inverted because 1,0 of dj is inverted and given to D), the dot is turned off and the dot is turned off. Other dots do not change.

While the erase output is being output, the bitmap data d ₁ , d ₂ , d _3, ... Dn to be displayed on the i-th row are transferred to the segment driving IC again without inverting the data (No. 13
This corresponds to the data for writing in the i-th row at D in the figure). After latching, the LCD drive output AC conversion signal M is changed from 0 to 1
Then, the output changes as shown in FIG. 5 (b). Thirteenth
In the figure, the i-th row write output at the segment output YSj corresponds to this. D = 1, that is, dj is 1 (in this case, dj
(0,1 is not inverted) is written and dot is O
N state. Other dots do not change.

While the write output is being output, the bitmap data d ₁ , d ₂ , d _3, ... Dn to be displayed on the (i + 1) th row are inverted and transferred to the segment driving IC (at D in FIG. 13). This corresponds to the (i + 1) -th row inverted inverted data for erasure). Hereinafter, the same applies.

During this period, the liquid crystal drive output AC signal M is 1, 0, 0,
1, 1, 0, 0, 1,... Are repeated.

The common driving IC includes a shift clock SC for determining the timing of shifting from the current scanning line to the next scanning line, a liquid crystal driving output AC signal M common to the segment driving IC, and line scanning data E (in the common driver mode). This corresponds to the display data D.). The timing of the operation of these and the segment driving IC is as shown in FIG.

The overall timing of the shift clock SC, the liquid crystal drive output AC signal M, the line scan data E, and the common output YCi is as shown in FIG.

In the above driving circuit, the bitmap data d ₁ , d ₂ , d _3, ... Dn for one row are inverted twice for the first time, and for the segment driving IC without being inverted for the second time. Although the data must be sent, the data transfer can be completed only once by providing the preprocessing circuit 400 shown in FIG. 15 in a stage preceding the segment driving circuit IC300. That is, the bit map data d ₁ , d ₂ , d ₃ ... Dn for one row are sent to the DATA terminal in FIG. 15 (clock φ). The data is stored in the latch circuit 401 once inverted by the inverter.
When the data for one row is completed, the data is transferred to the shift register circuit 402 that can be preset.

The shift register circuit 402 sends out the data as input data D of the driving circuit (corresponding to inverted data for erasing) at a transfer rate (clock CK) twice as fast as the clock φ, and inverts this data again (that is, The data is fed back as a serial input of the shift register circuit 402 (returning to the data before inversion).

In this manner, when one row of the erased inversion data is sent, the write data restored by the reinversion is sent out as the input data D of the drive circuit. When this is completed, since the data of the next row is ready in the latch circuit 401, it is preset and the above operation is repeated. FIG. 16 shows a timing chart of this operation.

If this method is used, bitmap data corresponding to a desired display pattern need only be input once to the DATA terminal of the preprocessing circuit 400.

For example, in order to display a pattern as shown in FIG. 17, 0, 1, 0, 1... 0, 0, 1, 0.
Serial data such as 1, 0, 0... 0, 0, 1, 1,. Then, a segment output, a common output, and a liquid crystal applied voltage as shown in FIG. 18 are obtained.

In the above method, as shown in FIG. 13, only the dots to be turned off in the erase output cycle are turned off, and only the dots to be turned on in the write output cycle are turned on. However, all dots may be turned off once in the erase output cycle, and only desired dots may be turned on in the write output cycle. This can be achieved by using the display data D enclosed in parentheses in the timing chart shown in FIG.

That is, if all the display data D is set to 1 instead of the inversion data for erasing, as shown in FIG. 5 (a), the liquid crystal drive output AC signal M is changed from 1 to 0 to select the data. You can erase all the dots in the line that has been set. Thereafter, the desired pattern may be transferred to the D terminal of the segment driving IC with the write data.

[Effects of the Invention] According to the present invention, currently available TN type liquid crystal panel driving
Since a ferroelectric liquid crystal panel can be driven by a simple driving circuit using an LSI, there is no need to design and develop a new LSI, and the cost can be reduced. In addition, since the correspondence between the bitmap data to be displayed and the IC control signal is good, the interface between the controller and the drive circuit is simplified, and the control procedure can be simplified.

[Brief description of the drawings]

FIG. 1 is an example of a circuit for carrying out the method of the present invention, FIG. 2 is an explanatory diagram of input / output signals of a driving IC, and FIGS. 3 (a) and 3 (b) show display data on a segment side and a common side. FIGS. 4 (a), (b) and 5 (a), (b) show a driving method 1 of the present invention, showing a relationship between an input terminal selected by a combination of alternating signals and an output voltage. 6 (a) (b) and 7 (a) (b) are diagrams for explaining the driving method 2 of the present invention, and FIGS. 8 (a) (b) and 9 (A) and (b) are diagrams for explaining driving method 3 of the present invention, and FIGS. 10 (a) and (b) and FIGS. 11 (a) and (b) are for explaining driving method 4 of the present invention. FIG. 12, FIG. 12 is a circuit diagram for implementing the method of the present invention, FIG. 13 and FIG. 14 are time charts for explaining the method of the present invention, FIG. 15 is a preprocessing circuit Figure, FIG. 16 a timing chart of the operation in the pre-processing circuit of FIG. 15, one pattern example of displaying FIG. 17 is a panel, FIG. 18 shows a time chart of a driving signal for displaying the pattern. 1: Ferroelectric liquid crystal panel 2: Driver IC 3: Controller

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02F 1/133 G09G 3/36

Claims (6)

(57) [Claims] 1. A dot is ON when D = 1, and a dot is OF when D = 0.
One of the four input terminals is selected according to a combination of two digital control signals of display data D representing F and a liquid crystal drive output AC conversion signal M, and the voltage input to the input terminal is output. A liquid crystal driving IC that outputs to the terminal to drive the segment side of the ferroelectric liquid crystal panel is used. Further, D = 1 indicates selection of a scanning line, and D = 0 indicates display data D indicating non-selection of a scanning line. , LCD drive output AC signal M
LCD drive that selects one of the four input terminals according to the combination of the two digital control signals and outputs the voltage input to the input terminal to the output terminal to drive the common side of the ferroelectric liquid crystal panel A method of driving a ferroelectric liquid crystal panel using an IC for display, wherein when the display data D is D = 1, the liquid crystal drive output AC signal M is set to 1, 0, 0 at adjacent times. , 1
When the display data D is D = 1, the liquid crystal drive output AC conversion signal M is changed to 0 at adjacent times.
By changing to 1, 1, 0, writing and erasing of a desired dot are performed continuously, and when the display data D is D = 0, the liquid crystal drive output AC signal M is changed from 0 to 1 at adjacent times. Alternatively, a method of driving a ferroelectric liquid crystal panel, wherein a display state of a dot is not changed even when it is changed from 1 to 0. 2. In a liquid crystal driving IC for driving a segment side, an input terminal selected when (D, M) = (1, 1) is set to an input terminal selected when V ₁ (1, 0). When the input terminal selected when the terminal is V ₂ (0, 1) is distinguished from the input terminal selected when V ₃ (0, 0) is V ₄ , the three-level liquid crystal driving voltage vs _{+ , v 0, vs - (vs} +> v 0> vs -)
_{The, V 1 = vs +, V} 2 = vs -, assigned as _{V 3 = V 4 = v 0} , and drives the segment side of the ferroelectric liquid crystal panel, further, for driving the liquid crystal to drive the common side In IC
The input terminal selected when (D, M) = (1, 1) is the input terminal selected when V ₂ (1, 0) is the input terminal selected when V ₁ (0, 1) When the input terminal selected when the terminal is V ₃ (0, 0) is distinguished from V ₄ , the two-level liquid crystal driving voltages vc ₊ , vc ₋ (vc ₊ > vc ₋ ), and V ₁ = V _{3 = vc +, V 2 =} V 4 = vc - allocated driving method of a ferroelectric liquid crystal panel can according to claim 1, wherein the wherein to drive the common side of the liquid crystal display dot matrix panel as. 3. An input terminal selected when (D, M) = (1, 1) is an input terminal selected when V ₁ (1, 0) in a liquid crystal driving IC for driving a segment side. When the input terminal selected when the terminal is V ₂ (0, 1) is distinguished from the input terminal selected when V ₃ (0, 0) is V ₄ , the four-level liquid crystal driving voltage vsh _{+ , vsh -, vsl +, vsl} - (vsh +>
_{vsl +> vsl -> vsh -} ) _{a, V 1 = vsh +, V} 2 = vsh -, V 3 = vs
l _+, V ₄ = vsl _- assigning as to drive the segment side of the ferroelectric liquid crystal panel, further, the liquid crystal driving IC for driving a common side,
The input terminal selected when (D, M) = (1, 1) is the input terminal selected when V ₂ (1, 0) is the input terminal selected when V ₁ (0, 1) When the input terminal selected when the terminal is V ₃ (0, 0) is distinguished from V ₄ , the four-level liquid crystal drive voltages vch ₊ , vch ₋ , vcl ₊ , vcl ₋ (vch ₊ >
_{vcl +> vcl -> vch -} ) _{a, V 1 = vc 1+, V} 2 = vc 1-, V 3 = vc
h _+, V ₄ = vch _- allocated ferroelectric liquid crystal panel driving method of a ferroelectric liquid crystal panel as claimed in claim 1, wherein it has been characterized to drive the common side of the like. 4. A dot is ON when D = 1, and a dot is ON when D = 0.
One of the four input terminals is selected according to a combination of two digital control signals of display data D representing F and a liquid crystal drive output AC conversion signal M, and the voltage input to the input terminal is output. A liquid crystal driving IC for driving the segment side of the ferroelectric liquid crystal panel by outputting to a terminal, and further, display data D indicating selection of a scanning line when D = 1 and non-selection of a scanning line when D = 0, One of the four input terminals is selected according to the combination of the two digital control signals of the liquid crystal drive output AC signal M, and the voltage input to the input terminal is output to the output terminal to output the voltage to the ferroelectric liquid crystal panel. A method for driving a ferroelectric liquid crystal panel using a liquid crystal driving IC for driving a common side, wherein when the display data D is D = 1, the liquid crystal driving output alternating signal M is adjacent to the liquid crystal driving output M. Times of Day 1, 0, 0, 1
The writing and erasing of the desired dot are continuously performed by changing the display data D. When the display data D is D = 1, the liquid crystal drive output AC signal M is set to 0 at adjacent times.
Erasing and writing of a desired dot are performed continuously by changing to 1, 1, 0. When the display data D is D = 0, the liquid crystal drive output AC signal M is changed from 0 to 1 at adjacent times. Alternatively, a method of driving a ferroelectric liquid crystal panel, wherein the state of a dot remains unchanged even when it changes from 1 to 0. 5. In a liquid crystal driving IC for driving a segment side, an input terminal selected when (D, M) = (1, 1) is an input terminal selected when V ₁ (1, 0). When the input terminal selected when the terminal is V ₂ (0, 1) is distinguished from the input terminal selected when V ₃ (0, 0) is V ₄ , the three-level liquid crystal driving voltage vs _{+ , v 0, vs - (vs} +> v 0> vs -)
_{The, V 1 = vs -, V} 2 = vs +, assigned as _{V 3 = V 4 = v 0} , and drives the segment side of the ferroelectric liquid crystal panel, further, for driving the liquid crystal to drive the common side In IC
The input terminal selected when (D, M) = (1, 1) is the input terminal selected when V ₂ (1, 0) is the input terminal selected when V ₁ (0, 1) When the input terminal selected when the terminal is V ₃ (0, 0) is distinguished from V ₄ , the two-level liquid crystal driving voltages vc ₊ , vc ₋ (vc ₊ > vc ₋ ), and V ₁ = V _{Three
= Vc -, V 2 = V} 4 = vc + assigned as in claim 4 characterized in that to drive the common side of the ferroelectric liquid crystal panel
A driving method of the ferroelectric liquid crystal panel described in the above. 6. In a liquid crystal driving IC for driving a segment side, an input terminal selected when (D, M) = (1, 1) is set to an input terminal selected when V ₁ (1, 0). When the input terminal selected when the terminal is V ₂ (0, 1) is distinguished from the input terminal selected when V ₃ (0, 0) is V ₄ , the four-level liquid crystal driving voltage vsh _{+ , vsh -, vsl +, vsl} - (vsh +>
_{vsl +> vsl -> vsh -} ) _{a, V 1 = vsh - V 2} = vsh +, V 3 = vsl -,
V ₄ = vsl ₊ assigned to drive the segment side of the ferroelectric liquid crystal panel and further drive the common side of the liquid crystal drive IC.
The input terminal selected when (D, M) = (1, 1) is the input terminal selected when V ₂ (1, 0) is the input terminal selected when V ₁ (0, 1) When the input terminal selected when the terminal is V ₃ (0, 0) is distinguished from V ₄ , the four-level liquid crystal drive voltages vch ₊ , vch ₋ , vcl ₊ , vcl ₋ (vch ₊ >
_{vcl +> vsl -> vch -} ) _{a, V 1 = vcl -, V} 2 = vcl +, V 3 = vc
5. The driving method for a ferroelectric liquid crystal panel according to claim 4, wherein the common side of the ferroelectric liquid crystal panel is driven by assigning h ₋ and V ₄ = vch ₊ .