JPH0485518A - Driving method for ferroelectric liquid crystal panel - Google Patents

Abstract

PURPOSE:To drive the ferroelectric liquid crystal panel by a simple driving circuit which uses a currently obtainable TN type liquid crystal panel driving LSI by following a control procedure by using a combination of display data and a liquid crystal driving output AC generating signal. CONSTITUTION:The panel 1 is driven by using a liquid crystal driving IC 2 which selects one of four input terminals according to the combination of the display data D representing an ON and an OFF state with dots 1 and 0 and two digital control signals of the liquid crystal driving output AC generating signal M and outputs a voltage inputted to the input terminal to an output terminal to drive the segment side of the ferroelectric liquid crystal panel 1 and an IC 2 which drives the common side of the panel 1 according to the combination of display data D representing a selected and an unselected state of a scanning line with D=1, 0 and the liquid crystal driving output AC generating signal M. At mutually adjacent time points, the signal M is varied from 1 to 0 or vice versa to turn off or on a desired dot.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for driving a ferroelectric liquid crystal panel using a TN type liquid crystal panel driving IC.

[Prior Art] In recent years, research on ferroelectric liquid crystals has been actively conducted. However, its operating mode is significantly different from that of conventional TN-type liquid crystals. Therefore, it has not been possible to use the liquid crystal driving LSI currently used for driving a TN type liquid crystal panel as it is for driving a ferroelectric liquid crystal panel.

Therefore, a new drive circuit was developed for ferroelectric liquid crystal panels (for example, Japanese Patent Laid-Open No. 62-87941),
Or TNy! i Analyze the LSI for driving LCD panels
Used as a multiplexer to distribute the ON and OFF waveforms generated by other function generators to the drive electrodes (
J, Phys, E: Sci, lnstrum, 21
(1988) 4 [1O-466].

However, in the former case, if the drive circuit were constructed using current ICs, the circuit would become huge as the number of drive electrodes on the panel increases, making it impractical to manufacture new LSIs. Then there was the problem of high costs.

Also, in the latter case, a function generator is required to generate ON waveforms and OFF waveforms, and a driving LS
There was a problem in that a complicated circuit was required to synchronize with I.

In view of these problems, the applicant has filed the patent application No.
No. 56298 proposes a method for driving a ferroelectric liquid crystal panel using a currently available Tll-type liquid crystal panel driving LSI.

[Problem to be solved by the invention] The driving method of the above-mentioned Japanese Patent Application No. 1-56298 is
It is excellent in that it drives a ferroelectric liquid crystal panel using an LSI for driving a fi liquid crystal panel. However, in this driving method, the correspondence between display data and LSI control signals was not very good, and there was room for improvement in terms of simplifying the control procedure.

The present invention was developed in view of the above circumstances, and it is possible to drive a ferroelectric liquid crystal panel using a simple drive circuit using a currently available TN type liquid crystal panel driving LSI and a simple control procedure. The purpose is to provide a driving method that makes it possible.

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

That is, in the method according to claim 1, when 4D=1 and the number of dots is O
Select one of the four input terminals to create a combination of two digital control signals: display data D indicating that the N and D dots are OFF, and a liquid crystal drive output alternating signal. A liquid crystal driving IC is used that outputs the voltage input to the terminal to the output terminal to drive the segment side of the ferroelectric liquid crystal panel.Furthermore, D=1 selects the scanning line, and 0 and 0 select the scanning line. One of the four input terminals is selected according to the combination of two digital control signals: display data D indicating non-selection of the LCD drive output AC signal -, and the voltage input to that input terminal is output. A method of driving a ferroelectric liquid crystal panel using a liquid crystal driving IC that outputs to a terminal to drive the common side of the ferroelectric liquid crystal panel, the liquid crystal drive output alternating signal being outputted at adjacent times. Turn off the desired dot by changing - from 1 to 0
By changing the above-mentioned liquid crystal drive output alternating signal plane from 0 to 1, a desired dot is turned on.

Preferably, at adjacent times, the liquid crystal drive output AC signal plane is set to 1.0.0.1 or 0, ■, 1.
Change it to 0.

Further, in the method according to claim 5, when D=1, the dot is ON;
Select one of the four input terminals according to the combination of the display data D, which indicates that D = 0, indicating that it is dot or OFF, and the two digital control signals on the LCD drive output AC signal plane, and connect it to that input terminal. A liquid crystal driving IC is used that outputs the input voltage to the output terminal to drive the segment side of the ferroelectric liquid crystal panel. Furthermore, D=1 selects the scanning line, and O-0 selects the non-scanning line. Select one of the four input terminals to create a combination of two digital control signals: the display data D representing selection and the LCD drive output alternating signal, and transfer the voltage input to that input terminal to the output terminal. There is a method of driving a ferroelectric liquid crystal panel using a liquid crystal driving IC that outputs and drives the common side of the ferroelectric liquid crystal panel, and the above-mentioned liquid crystal drive output alternating signal is outputted at adjacent times to drive the common side of the ferroelectric liquid crystal panel. By changing from 1 to 0, the desired dot is turned on, and by changing the liquid crystal drive output AC conversion signal from 0 to 1, the desired dot is turned off.

Preferably, at adjacent times, the liquid crystal drive output alternating signal - is set to 1, O, o, 1 or 0.1, ■,
Change it to 0.

The solution will be specifically explained below.

As shown in FIG. 1, a driving device for carrying out this driving method includes a ferroelectric liquid crystal panel 1, a driving device C2 for driving the panel 1, and a controller 3.

The ferroelectric liquid crystal panel 1 used is one that is in a bistable state and has clear threshold characteristics.

That is, when an applied voltage pulse or a positive voltage pulse with a certain pulse intensity τ that is higher than a certain threshold value Vth00) is applied, writing is performed and the display is turned on (lighting state) by V, − When a negative voltage pulse below Vth is applied, erasing is performed and the display turns 0FF (off state).
If the voltage pulse has an absolute value of VLh or less, the display state remains unchanged and the current display is maintained.

The common and segment drive IC2 uses display data D.
, inputs the liquid crystal drive output AC peg number and liquid crystal drive voltage, and outputs the liquid crystal drive output (see Figure 2).

Here, when driving the segment side of the IC (segment driver mode), the liquid crystal driving IC simultaneously drives a plurality of segment electrodes of one normal liquid crystal panel. The display data D corresponding to each of the plurality of electrodes is serially transferred to the driving IC (or may be transferred in parallel to improve the transfer speed), and is internally latched to control the output. T
When used for an N liquid crystal panel, D-1 and Q are the dots on the corresponding segment electrodes (ON).
(lighted state), 0FF (lighted out state).

When driving the IC or the common side (common driver mote), display data D.1.0 corresponds to selection or non-selection of the corresponding common electrode.

In both the segment driver mote and the common driver mote, the LCD drive output AC conversion signal is
When used for TN liquid crystal panel, one time series is l.
By setting 1l=1.0.1,0-..., the output voltage is switched between positive and negative to convert to AC, and the DC component of the voltage applied to the liquid crystal is set to 0 to suppress chemical deterioration of the liquid crystal. M differs from D in that V does not have a latch mechanism and is common to all outputs.

Furthermore, the liquid crystal drive voltage is input to the input terminals V, ~v4, and when used for a TN liquid crystal panel 1, normally, V,
)Vff)V, )V, (7) Set the voltage.

On the other hand, there are a plurality of output terminals Y (Y, -Yo) for liquid crystal drive output, and they simultaneously drive a plurality of electrodes on the common side and segment side of the liquid crystal panel.

Next, the relationship between the display data O1 liquid crystal drive output AC peg score, the selected input terminals V, ~v4, and the output Y will be shown.

There are four combinations of digital control signals of display data D and liquid crystal drive output AC signal -, and one of the four input terminals V, , V, , ■3, V4 is selected according to each combination. The voltage applied to the selected input terminal appears at the output terminal Y. The person in charge of 5ill.

In segment driver mode, (D, M)・(1,1) = (1,0) = (0,1) - (0,0), input terminal V, , input terminal V2, input terminal When v3, input terminal v4, in common triver mote, (D, M) - (1, I) throat input terminal v2, - (1,
0), the input terminal v1; -(0, 1), the input terminal V3; and -(0, 0), the input terminal v4.

Normally, when used for a TN liquid crystal panel, in segment driver mode, four-level voltages Vsh++Lh-+Ll*, L+-(Vwh*)Ll+
)Vtl->V, h-) to V +-V, h,, Vz-V-h-, V z-V-1,
, V 4-V-1- (Figure 3(a)).

In addition, in the common driver mote, the four-level voltage Veh*+vch-+Vcl*+Vcl-(Veh, *
)VatssonVc+ -)Vch-)V,=V,,h,,v2-veh-+V1=V
s+, V2=Vsvc, +, V1=Vs+, V2=Vs
vc, - (Fig. 3(b)).

The whole thing is vwh+”Vch*〉Vel+)L
Vch-Lh- (7) relationship.

As a method for driving the above-mentioned ferroelectric liquid crystal panel 1 using the driving IC 2, there are the following methods.

Driving method l In segment driver mode, three-level liquid crystal driving voltages Vo, vo, ■, -(Vs+>V0>Vs, .)Vo)
V w-) to V +-V, *, V z-V-, V y-V
The segment side of the ferroelectric liquid crystal panel is driven by assigning it as a-Vo (Fig. 4(a)). In the common triver mode, the two-level liquid crystal drive voltage ■e0, V, (V, )VC-) are assigned as v, -V3-Vo, Vz=V4-VO-1 to drive the common side of the ferroelectric liquid crystal panel (FIG. 4(b)).

However, overall, V,,)Vc and >Vo>V,, ->
There is a relationship of V, -.

By setting the voltage in this way, display data D in the drive IC
After determining that, if the LCD drive output AC conversion signal - is changed from 1 to 0,
As shown in No. 5 [21(a)], the output changes, and the voltage applied to the liquid crystal also changes accordingly.

Here, the common electrode is selected and the segment electrode is ON.
In this state, a large positive voltage is applied to the liquid crystal (the direction from the segment electrode to the common electrode is positive), and a large negative voltage (absolute value or greater than vth) is applied to the liquid crystal. The display on the ferroelectric liquid crystal panel is erased.

When the common electrode is in the non-selected state or the segment electrode is in the OFF state, only a small voltage (absolute value or less than Vth) is applied to the liquid crystal, so the display state of the ferroelectric liquid crystal panel does not change. In other words, the liquid crystal drive output alternating signal -
By changing from 1 to 0, a desired dot (the dot D-1 on the segment electrode) can be erased.

In either case, change the liquid crystal drive output AC signal - from 1 to 0.
When the voltage is changed to 1, the positive and negative voltages are applied to the liquid crystal symmetrically, so that the net DC voltage component is averaged to 0, and deterioration of the liquid crystal can be prevented.

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

Here, the common electrode is selected and the segment electrode is turned on.
In the state of , a large negative voltage is applied to the liquid crystal when the value is 1, and then a large positive voltage (absolute value or greater than Vth) is applied to the liquid crystal, causing writing to occur on the ferroelectric liquid crystal panel.

When the common electrode is in the non-selected state or the segment electrode is in the OFF state, only a small voltage is applied to the liquid crystal, so the display state of the ferroelectric liquid crystal panel does not change. By changing from 0 to 1, the desired dot (D-1 on the segment electrode)
A message appears.

When changing the liquid crystal drive output alternating current signal from 0 to 1, voltages with positive and negative polarity are applied to the liquid crystal, so that the net DC voltage component is averaged to 0, thereby preventing deterioration of the liquid crystal.

By changing the liquid crystal drive output alternating signal range from 1.0 to 0.1, erasing and writing of desired dots can be performed continuously.

By changing the AC signal range of the liquid crystal drive output from 0.1 to 1 to 0, writing and erasing of desired dots can be performed continuously.

In this method, since only the dots desired to be turned off can be erased during the erasing process, there is no problem even if the writing process occurs before the erasing process.

In the 111 diagonal segment trihamote, the three-level liquid crystal drive voltage V, , Vo, V, -(V,.)V0)Vll-) is V
+=V--, V x=V--, V x-V 4-vo
In order to drive the segment side of the ferroelectric liquid crystal panel by allocating it as shown in Fig. 6(a)), for the common triver mote, the two-level liquid crystal driving voltage Ve, , Ve − (Vce) Ve −) is assigned as follows. V, -V, -V
The common side of the ferroelectric liquid crystal panel is driven by assigning signals such as ゎ-, V2-V, and -Ve (FIG. 6(b)).

However, in total, V, +)Vc◆)Vo)V, -)V
, -.

Now, based on the same idea as the drive method engineering, if we change the LCD drive output AC signal range from 1 to 0 as shown in Figure 7, we get:
The desired dot can be written (Fig. 7(a)), and when the LCD drive output AC conversion signal range is changed from O to 1,
Desired dots can be erased (Fig. 1s7 (b)).

By changing the liquid crystal drive output alternating current signal M to O51, 1, 0, erasing and writing of desired dots can be performed continuously.

By changing the liquid crystal drive output AC signal range from 1.0.0 to I, writing and erasing of desired dots can be performed continuously.

In this method, compared to driving method 1, the roles of 0 and ■ in the liquid crystal drive output alternating current signal range are reversed.

Driving method 3 Segment driver mode has four levels of liquid crystal driving voltage V sh*, Lh-+Vml*, Vsl-(Vs+>V
0>Vssh*>Vl+++>νml->V, h-) as V'+=Lh+, V, V, h-5Vx-VII+,
, V, -Vl-1 to drive the segment side of the ferroelectric liquid crystal panel (FIG. 8(a)).

The common driver mode has four levels of liquid crystal drive voltages Veh*, Vch-1Vel+, and Vcl-(Vch*).
V,l+)Vcl-)Vch-)vlgve,,,V,-Vc,-1V,-Vch,,
V4-V, h- are assigned to drive the common side of the ferroelectric liquid crystal panel (FIG. 8(b)).

r, -Tashi, overall Ha, Lh+〉Vel*)Vel-)
Vsh-+■ch*)Ve++)Vcl->veh-
+ v*h+〉Vch+〉Vl;g-)Vgl1- (
1) Being in a relationship.

Now, based on the same idea as driving method 1, if the liquid crystal drive output AC conversion signal M is changed from 1 to 0 as shown in FIG.
To erase the desired dot (Fig. 9(a)), change the liquid crystal drive output AC signal to 0 or 61.
Only desired dots can be written (FIG. 9(b)).

By changing the liquid crystal drive output AC peg number from 1 to 1, it is possible to continuously erase and write desired dots.

The liquid crystal drive output AC signal is set to 0.1. ．． If the value is changed to 1.0, desired dots can be written and erased continuously.

In this method, the voltage waveform actually applied to the liquid crystal can be the same or the same, although the method of applying the liquid crystal driving voltage is different compared to the driving method 1.

Driving method 4 Segment driver mode uses 4-level liquid crystal driving voltage V e h O1v* h −% vII 1 +, V
sl-(Vs+>V0>Vs, h*>V1=Vs+, V
2=Vs++)Vel-)V1=Vs+, V2=Vsh
-) to V, -V, h-1v 2-V1=Vs+, V2=
Vsb,, V3-V,, -2V4-V,,.

The segment side of the ferroelectric liquid crystal panel is driven as shown in FIG. 1O (a).

The common driver mode has four levels of liquid crystal drive voltages Vah*, ve h −, ve I *, Vel−(V
ch*)Vel*)Val-)V6H-) to V, = shi, , I-1Vl-VeI+, V, -V, h
-1V 4-VOh* is assigned to drive the common side of the ferroelectric liquid crystal panel (Fig. 1O(b)).

Tatashi, whole body, Lh+〉Vel*)Vgl-)Ll
+-+Veh *)■,,I *>Ve 1-)Vah
-, Lh,>Veh,) V, h-)Lh-.

Here, based on the same idea as driving method 1, the 11th
As shown in the figure, when the liquid crystal drive output AC dowel is changed from 1 to 0,
The desired dot can be written (Fig. 1.1 (a)), and when the liquid crystal drive output alternating signal amount is changed from 0 to 1,
The desired dots can be erased (FIG. 11(b)).

By changing the liquid crystal drive output AC signal rate from 0 to 1 to 1.0, erasing and writing of desired dots can be performed continuously.

By changing the liquid crystal drive output AC pin number from 1.0.0.1, writing and erasing of desired tones can be performed continuously.

In this method, compared to driving method 3, the roles of 0 and 1 of the liquid crystal drive output AC conversion signal - are switched.

In either method, the voltage setting does not have to be exact. For example, in driving method 1, segment side Te V
x-1V 4-Vo, common side TeV, -V: I-V
It is preferable that it is C4, V 2-V or -Vc-.

However, whether the IC used is V r>V x>V 4) V 2
If required, set voltage to V. ,V...
A little bit off from ve-.

Segment side V, >V, >V, common side V1)V
The following relationship may be satisfied: C,)V3,V,)V,)V2.

However, V:l, V4 and V on the segment side.

The difference between: r side te (7) V r , V x t V
,, (7) Difference, V t , the difference between V 4 and vc- is
It is desirable to keep it below IH of the total liquid crystal drive power supply voltage (V, -V,). If you exceed IH, rewriting the liquid crystal may not work.

The same applies to driving methods 2 to 4.

[Example] An example of the present invention will be described below with reference to the drawings.

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

In the figure, 100 is a ferroelectric liquid crystal panel (simple matrix display type), and 200 is a common drive IC 130.
0 is the segment drive 1G, 400 is the preprocessing circuit provided before the segment drive IC, and 500 is the drive IC 2.
00, drive IC 300 and/or preprocessing circuit 40
0, a controller (CPU) sends a control signal through a boat 501, and 600 is a liquid crystal drive level circuit.

The preprocessing circuit 400 does not necessarily have to be included, as will be explained in detail later.

That is, the output of the port may be directly input to the D terminal of the segment drive IC. In this case, the function of the preprocessing circuit 4 (10) is performed by the controller 500.

Here, from the liquid crystal drive level circuit 600, a common drive I
The liquid crystal drive voltages V, ..., Ve, Vo, Vc-, V, - supplied to C200 and the segment drive IC 300 are the power supply voltages VLe*+VLe-(VL, a*>VL, c
-) is created by dividing the voltage with a resistor.

At this time, in order to set the drive method to the 173 bias method, vl. -vc, ・Ve and -Vo=Vo V,,
−=Vc−−V, −(n0).

Next, the method of this embodiment will be explained based on the time chart shown in FIG. First, an example in which no preprocessing circuit is used will be described.

The segment drive IC is controlled as follows. , bitmap data d, cf to be displayed on the first line
2, d, -d, (the dot lights up when dJ = 1, and goes off when d = 0), first, the data obtained by inverting 1.0 of dJ is given as the display data D (see Fig. 13). (This corresponds to the inverted data for erasing the i-th row in D.)

CK is a shift clock for serial data transfer. - When n rows of data have been transferred into the segment drive IC, the latch clock LC is brought down and the data is latched.

Thereafter, when the liquid crystal drive output AC signal - is changed from 1 to 0, the output changes as shown in FIG. 5(a). 13th
The time chart in the figure corresponds to the i-th line erase output of segment output YSJ.

o-i, that is, d, or 1) (the 1 and 0 of d are inverted and given to D, so it is reversed) is erased, and the dot becomes OFF. Other dots remain unchanged.

While the erase output is being output, the bitmap data d+, dz, dU...dn to be displayed on the i-th row is transferred to the segment drive IC again without inverting the data (the 13 [corresponding to the i-th row write data at 0 of J], after latching, when the liquid crystal drive output alternating signal - is changed from 0 to 1, the output changes as shown in FIG. 5(b). In Figure 13, the segment output YS is the i-th line write output, which corresponds to D-.
1, that is, dJ or 1 (dJ 1.0 is not inverted this time) is written and the dot becomes ON. Other dots remain unchanged.

While the write output is being output, the bitmap data dI, dz, ds-"dn to be displayed on the i+1st row is inverted and transferred to the segment drive IC (13th
This corresponds to i◆inverted data for erasing in the first row at the bottom of the figure), and the same applies hereafter.

During this period, the liquid crystal drive output AC signal layer was 1.0.0, ■,
1. Repeat 0.0, l...

Common drive 1c includes a shift clock SC that determines the timing of shifting from the current scanning line to the next scanning line, a liquid crystal drive output AC signal layer common to the segment drive IC,
It is controlled by line scanning data E (corresponding to display data D in the common driver mode). The operation timings of these and segment drive (C) are as shown in FIG.

These shift clock SC1 liquid crystal drive output alternating signal -
, line scanning data E, and common output YC, the overall timing is as shown in FIG.

In the above drive circuit, bitmap data d+, d2 . di...-d twice, the first time is 1.
Either it is necessary to invert 0 and send it to the segment drive IC without inverting it the second time, or it is possible to perform data transfer by providing the preprocessing circuit 400 shown in FIG. You can do it once. That is, - rows of bitmap data d,,d
, d, -dn are sent to the DATA terminal in FIG. 15 (clock φ), the data is inverted by an inverter and temporarily stored in the latch circuit 401. - When all the data for the rows are complete, the data is transferred to the presettable shift register circuit 402.

The shift register circuit 402 sends out data as input data D to the drive circuit (corresponding to inverted data for erasing) at a transfer rate (clock GK) twice that of the clock φ, and also prevents this data from being inverted again (i.e. , the data is returned to the data before inversion) as a serial input of the shift register circuit 402.

In this way, when the inverted data for erasing for - rows is sent out, the data for writing which is re-inverted and returned to its original state is sent out as the input data D of the drive circuit. When this is finished, the data for the next row A timing chart of this operation is shown in FIG. 16, in which the latch circuit 401 is preset and the above operation is repeated.

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

For example, in order to display a pattern like that shown in Figure 17, the DATA terminal should be connected to 0.1.0.1・-0, 0, i, o-.
- Enter serial data such as bow, 1, 0.0, -0, 0, lj... Then, the segment side force, common output, and liquid crystal applied voltage as shown in FIG. 18 are obtained.

In the above method, as shown in FIG. 13, only the dots desired to be in the OFF state are turned off in the erase output cycle, and only the dots desired to be in the 0)l state are turned on in the write output cycle. However, all the dots may be temporarily turned off in the erase output cycle, and only desired dots may be turned on in the write output cycle. In order to do this, display data O such as ( ) and << in the timing chart shown in FIG. 13 may be used.

That is, if all the display data D is set to 1 instead of the inverted data for erasing, then by changing the liquid crystal drive output alternating signal M from 1 to O, as shown in FIG. 5(a), This will erase all dots in the selected row. Thereafter, a desired pattern may be placed on the write data and transferred to the D terminal of the segment drive 1c.

[Effects of the Invention] According to the present invention, one ferroelectric liquid crystal panel can be driven by a simple drive circuit using a currently available TN type liquid crystal panel driving LSI, so a new LSI can be designed and developed. It's not necessary and the cost can be reduced.

Moreover, since there is good correspondence between the bitmap data to be displayed and the IC control signals, the interface between the controller and the drive circuit can be simply established, and the control procedure can be simplified.

[Brief explanation of the drawing]

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 (b).
) is an input terminal selected by a combination of 1 display data and AC conversion signal on the segment side and common side,
4(a)(b) and 5(a)(b) are diagrams showing the relationship between output voltages. FIGS. 7(a) and (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 the driving method 3 of the present invention. Diagrams for explanation, 10th fg(a)(b) and 1112th(a)
(b) is a diagram for explaining driving method 4 of the present invention, FIG. 12 is a circuit contingency for implementing the method of the present invention, and FIGS. 13 and 14 are for explaining the embodiment method of the present invention. 15 is a timing chart of the preprocessing circuit contingency, and FIG. 16 is a timing chart of the operation in the preprocessing circuit of FIG. 15. Figure 17 is an example of the pattern displayed on the panel, Figure 18 [
7 shows a time chart of drive signals when displaying the above pattern. l 2 Ferroelectric liquid crystal panel: Drive IC 3: Controller

Claims (8)

[Claims] (1) Dot is ON when D=1, dot is OFF when D=0
One of the four input terminals is selected according to the combination of two digital control signals: display data D indicating that A liquid crystal driving IC is used to drive the segment side of the ferroelectric liquid crystal panel by outputting the data to the ferroelectric liquid crystal panel; LCD drive output AC signal M
A liquid crystal drive that selects one of the four input terminals according to a combination of two digital control signals, and outputs the voltage input to that 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 driving a ferroelectric liquid crystal panel, which turns off a desired dot by changing the liquid crystal drive output alternating signal M from 1 to 0 at adjacent times. A method for driving a ferroelectric liquid crystal panel, characterized in that a desired dot is turned on by changing a drive output AC signal M from 0 to 1. (2) The ferroelectric liquid crystal panel according to claim 1, wherein the liquid crystal drive output alternating signal M is changed to 1, 0, 0, 1 or 0, 1, 1, 0 at adjacent times. Driving method. (3) In the liquid crystal driving IC that drives the segment side, input terminals selected when (D, M) = (1, 1) are set to V_1 (1,
0), the input terminal selected when V_2 (0, 1) is V_3, and the input terminal selected when V_4 (0, 0) is 3 levels. LCD drive voltage V_s_+, V_0, V_s_-
(V_s_+>V_0>V_s_-), V_1=V_
s_+, V_2=V_s_-, V_3=V_4=V_0
In addition, in the LCD driving IC that drives the common side, the input terminal selected when (D, M) = (1, 1) is V_2. (1,
0), the input terminal selected when V_1 (0, 1) is V_3, and the input terminal selected when V_4 (0, 0) is 2 levels. LCD drive voltage V_c_+, V_c_-(V_c
___+>V_c_-), V_1=V_3=V_c_+,
3. The method of driving a ferroelectric liquid crystal panel according to claim 1, wherein the common side of the liquid crystal display dot matrix panel is driven by allocating voltages as V_2=V_4=V_c_-. (4) In the liquid crystal driving IC that drives the segment side, input terminals selected when (D, M) = (1, 1) are set to V_1 (1,
0), V_2 (0, 1), and V_3 (0, 0), the input terminal selected is V_4. (V_s_h_+>V_s_i_+>V_s_i_->
V_s_h_-), V_1=V_s_h_+, V_2
=V_s_h_-, V_3=V_s_i_+, V_4=
In a liquid crystal driving IC that allocates V_s_i_- to drive the segment side of a ferroelectric liquid crystal panel and further drives the common side,
The terminal selected when (D, M) = (1, 1) is set to V_2 = (1,
0), terminals selected when V_1=(0, 1), terminals selected when V_3=(0, 0), and terminals selected when V_4=, 4-level liquid crystal drive voltage V_c_h_+, V_c_h_-
, V_c_i_+, V_c_i_-(V_c_h_+>
V_c_i_+>V_c_i_->V_c_h_-), V_1=V_c_i_+, V_2=V_c_i_-,
3. The method of driving a ferroelectric liquid crystal panel according to claim 1, wherein the common side of the ferroelectric liquid crystal panel is driven by allocating V_3=V_c_h_+ and V_4=V_c_h_-. (5) When D=1, the dot is ON, when D=0, the dot is OFF
One of the four input terminals is selected according to the combination of two digital control signals: display data D indicating that A liquid crystal driving IC is used to drive the segment side of the ferroelectric liquid crystal panel by outputting the data to the ferroelectric liquid crystal panel; LCD drive output AC signal M
A liquid crystal drive that selects one of the four input terminals according to a combination of two digital control signals, and outputs the voltage input to that 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 driving a ferroelectric liquid crystal panel, the method comprises: turning on a desired dot by changing the liquid crystal drive output alternating signal M from 1 to 0 at adjacent times;
A method for driving a ferroelectric liquid crystal panel, characterized in that a desired dot is turned off by changing the liquid crystal drive output alternating signal M from 0 to 1. (6) The ferroelectric liquid crystal panel according to claim 5, wherein the liquid crystal drive output alternating signal M is changed to 1, 0, 0, 1 or 0, 1, 1, 0 at adjacent times. Driving method. (7) In the liquid crystal driving IC that drives the segment side, input terminals selected when (D, M) = (1, 1) are set to V_1 (1,
0), the input terminal selected when V_2 (0, 1) is V_3, and the input terminal selected when V_4 (0, 0) is 3 levels. LCD drive voltage V_s_+, V_0, V_s_-
(V_s_+>V_0>V_s_-), V_1=V_
s_-, V_2=V_s_+, V_3=V_4=V_0
In a liquid crystal driving IC that drives the segment side of a ferroelectric liquid crystal panel and also drives the common side,
The input terminal selected when (D, M) = (1, 1) is set to V_2 (1,
0), the input terminal selected when V_1 (0, 1) is V_3, and the input terminal selected when V_4 (0, 0) is 2 levels. LCD drive voltage V_c_+, V_c_-(V_c
__+>V_c_-), V_1=V_3=V_c_-,
7. The method of driving a ferroelectric liquid crystal panel according to claim 5, wherein the common side of the ferroelectric liquid crystal panel is driven by allocating voltages as V_2=V_4=V_c_+. (8) In the liquid crystal driving IC that drives the segment side, input terminals selected when (D, M) = (1, 1) are set to V_1 (1,
0), the input terminal selected when V_2 (0, 1) is V_3, and the input terminal selected when V_4 (0, 0) is 4 levels. LCD drive voltage V_s_h_+, V_s_h_-
, V_s_i_+, V_s_i_−(V_s_h_+>
V_s_i_+>V_s_i_->V_s_h_-), V_1=V_s_h_-, V_2=V_s_h_+,
In a liquid crystal driving IC that allocates V_3=V_s_i_- and V_4=V_s_i_+ to drive the segment side of a ferroelectric liquid crystal panel and further drives the common side,
The terminal selected when (D, M) = (1, 1) is V_2 (1, 0)
When distinguishing the terminal selected when V_1 (0, 1) is V_3 and the terminal selected when V_4 (0, 0) is V_4, the 4-level liquid crystal drive voltage V_c_h_+ , V_c_h_-
, V_c_i_+, V_c_i_-(V_c_h_+>
V_c_i_+>V_c_i_->V_c_h_-), V_1=V_c_i_-, V_2=V_c_h_+,
7. The method of driving a ferroelectric liquid crystal panel according to claim 5, wherein the common side of the ferroelectric liquid crystal panel is driven by allocating V_3=V_c_h_- and V_4=V_c_h_+.