JP4737825B2 - Liquid crystal driving voltage generation circuit and liquid crystal display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal driving voltage generating circuit used for a simple matrix type liquid crystal display panel. Furthermore, the present invention relates to a liquid crystal driving device equipped with this liquid crystal driving voltage generating circuit.
[0002]
[Prior art]
Usually, in order to drive a simple matrix type liquid crystal panel, a voltage of 6 levels is generated by a voltage generation circuit for driving liquid crystal, and this voltage is driven through a driver IC for driving liquid crystal. Since the liquid crystal in the liquid crystal panel deteriorates in characteristics when a DC voltage is applied for a long time, the applied voltage is converted into an alternating voltage using the six-level voltages V0 to V5 generated by the liquid crystal driving voltage generation circuit, and the average voltage is set to 0V. ing.
[0003]
In the liquid crystal display panel using the six-level voltages V0 to V5, the waveform during operation will be described with reference to FIG. 7. During the positive period, the selection voltage of the scan electrode is V5, the non-selection voltage is V1, and the signal The lighting voltage of the electrode is V0 and the non-lighting voltage is V2. On the other hand, during the negative polarity period, the scanning electrode selection voltage is V0, the non-selection voltage is V4, the signal electrode lighting voltage is V5, and the non-lighting voltage is V3. In this way, the voltage is applied to make an alternating current.
[0004]
Among such liquid crystal driving voltage generation circuits that generate 6-level voltages, a technique for reducing power consumption has been proposed (see Japanese Patent Laid-Open No. 10-31200).
[0005]
This technique will be described with reference to FIG. The figure corresponds to FIG. 2 of the publication.
According to the voltage generation circuit for driving a liquid crystal, the voltage supply source 1, the resistors R1 to R5 connected in series for dividing the voltage of the voltage supply source 1, and the voltage obtained by the resistors R1 to R5 are supplied to the liquid crystal display unit. Voltage-follower-connected high-voltage side operational amplifiers OP1 and OP2 and low-voltage side operational amplifiers OP3 and OP4, and resistors R6 and R7 for generating and maintaining a voltage VM near the middle of the voltage supply source 1, It comprises transistors Tn and Tp and a capacitor C1.
[0006]
The voltage obtained from the voltage supply source 1 is divided by resistors R1 to R5 connected in series, and the divided voltage is input to operational amplifiers OP1 to OP4 connected in voltage follower, and the voltages V1 to V4 are output. Is done. These four voltage levels and the voltage of the voltage supply source 1 itself, V0 and V5, are a total of six levels of voltages that drive the liquid crystal panel.
[0007]
Incidentally, V0 to V5 have a relationship of approximately V0-V1 = V1-V2 = V3-V4 = V4-V5.
[0008]
Although depending on the threshold voltage and driving duty of the liquid crystal, V0-V1 is about 1-2V and V0-V5 is about 10-40V.
[0009]
The transistors Tn and Tp are means for generating an intermediate potential VM obtained by dividing V0 and V5 into approximately two, and a capacitor C1 is inserted between the VM and V5.
[0010]
V0 is connected to the positive power supply terminals of the operational amplifiers OP1 and OP2 operating on the high voltage side, and VM is connected to the negative power supply terminal. VMs are connected to the positive power supply terminals of the operational amplifiers OP3 and OP4 operating on the low voltage side, and V5 is connected to the negative power supply terminal.
[0011]
As described above, V0, V1, V2, and V5 are used during the positive polarity period when the liquid crystal panel is driven, and V0, V3, V4, and V5 are used during the negative polarity period. , The high-voltage side operational amplifiers OP1 and OP2 operate, and the low-voltage side operational amplifiers OP3 and OP4 operate during the negative polarity period.
[0012]
Therefore, with the circuit configuration as described above, the operating voltage of each operational amplifier is about half of the voltage of the voltage supply source 1 compared to the case where all of OP1 to OP4 are operated at a voltage of V0-V5. Reduces power consumption due to operation. At the same time, in the positive polarity period in which the liquid crystal is driven by the high voltage side operational amplifier, the charge due to the consumption current of the high voltage side operational amplifier is temporarily stored in the capacitor C1, and during the negative polarity period in which the liquid crystal is driven by the low voltage side operational amplifier. Can operate the operational amplifier on the low voltage side with the electric charge stored in the capacitor C1, so that the power consumption of the operational amplifier due to charging / discharging of the liquid crystal panel can be reduced to almost half. As a result, the entire voltage generating circuit for driving the liquid crystal Power consumption can be reduced.
[0013]
The capacitors C2 to C5 are capacitors of about several μF each, and function to stabilize the voltages V1 to V4.
[0014]
[Problems to be solved by the invention]
However, in the liquid crystal driving voltage generation circuit presented in the above-mentioned Japanese Patent Application Laid-Open No. 10-31200, the power consumption is approximately halved compared to the case where all the operational amplifiers OP1 to OP4 are operated with the power supply voltage of V0-V5. However, the actual voltage between the power supply terminals is still higher than the voltage between the power supply terminals required by the operational amplifier with respect to the voltage output from the operational amplifier. Further, since the voltage between the power supply terminals is still high, the power consumption in the operational amplifier in the liquid crystal driving voltage generation circuit is not sufficiently small.
[0015]
An allowable value of power consumption called allowable loss is defined for the operational amplifier. If this value is exceeded, the operational amplifier itself is permanently destroyed by the heat generated by the power consumption. The value of the allowable loss varies depending on the ambient temperature. In a general operational amplifier, for example, in an environment where the ambient temperature is 70 ° C., the allowable loss is about 2/3 to half of the allowable loss at 25 ° C.
[0016]
Therefore, the conventional liquid crystal driving voltage generation circuit has a problem of the power consumption of the operational amplifier and cannot be used in a high temperature environment.
[0017]
In addition, since the voltage between the power supply terminals of the operational amplifier is still large, there is a problem that an inexpensive operational amplifier with a smaller rated voltage between the power supply terminals of the operational amplifier cannot be used.
[0018]
The present invention has been completed in view of the above circumstances, and its purpose is to disperse the power consumption of the operational amplifier and reduce the power consumption of the operational amplifier almost without changing the overall power consumption, thereby even in a high temperature environment. An object of the present invention is to provide a liquid crystal driving voltage generation circuit that can be used.
[0019]
Another object of the present invention is to provide a liquid crystal driving voltage generating circuit using an inexpensive operational amplifier having a small voltage rating between power supply terminals.
[0020]
Still another object of the present invention is to provide a liquid crystal display device provided with such an excellent liquid crystal drive voltage generation circuit.
[0021]
[Means for Solving the Problems]
The voltage generation circuit for driving a liquid crystal according to the present invention includes a voltage obtained by dividing a voltage of a voltage supply source by a plurality of first voltage dividing resistors connected in series, via each operational amplifier in which a voltage follower connection is made. In the liquid crystal driving voltage generating circuit supplied to the liquid crystal driving driver IC, the first voltage and the second voltage obtained by dividing the voltage of the voltage supply source into three by the second voltage dividing resistor are respectively held. comprising a capacitor, a first transistor to keep the first voltage in a predetermined range, and a second transistor to keep the second voltage to a predetermined range, wherein the first voltage is higher than said second voltage, connect the negative power supply terminal of the high voltage side of the operational amplifier of the operational amplifier to the first voltage, connect the positive power supply terminal of the low voltage side operational amplifier to the second voltage, the second trunk and said first transistor A third transistor connected in series with the first transistor and the second transistor, and between the first transistor and the third transistor, and And a resistor connected in series with the first transistor and the third transistor .
[0022]
The liquid crystal display device of the present invention, the electrode patterns arranged in one direction, and while a substrate having an alignment film, an electrode pattern arranged in the other direction, and a second substrate having an alignment film through a liquid crystal layer by opposed to the liquid crystal display panel without a front view area by intersecting both the electrode pattern Te, a liquid crystal driving driver IC for displaying driving the liquid crystal display panel, a liquid crystal driving voltage generation circuit of the present invention formed by disposed.
[Action]
As described above, the voltage generation circuit for driving a liquid crystal according to the present invention can reduce the voltage between the power supply terminals of the operational amplifier in the voltage generation circuit for driving the liquid crystal as compared with the conventional circuit. The power consumption of the operational amplifier due to the current consumed by charging / discharging the panel is reduced. The decrease in power consumption of the operational amplifier due to the decrease in the voltage between the power supply terminals is consumed in the transistor Tn2.
[0023]
As described above, in the conventional voltage driving circuit for liquid crystal driving, the power consumption in the operational amplifier can be reduced by replacing a part of the loss generated only by the operational amplifier with the transistor. The liquid crystal driving voltage generation circuit can be used in a higher temperature environment while maintaining the low power consumption effect of the entire liquid crystal driving voltage generation circuit.
[0024]
In addition, since the voltage between the power supply terminal terminals can be reduced at the same time, it is possible to use an operational amplifier with a smaller voltage rating between the power supply terminals.
[0025]
Further, in the liquid crystal display device of the present invention, by mounting the liquid crystal driving voltage generation circuit of the present invention, the low power consumption effect when using the conventional liquid crystal driving voltage generation circuit is maintained, and the ambient temperature Excellent driving performance can be achieved even in higher environments.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings.
(Example 1)
FIG. 1 shows a voltage generation circuit for driving a liquid crystal according to the present invention.
[0027]
In this voltage generation circuit for driving a liquid crystal, a voltage supply source 1, series-connected resistors R1 to R5 that divide the voltage of the voltage supply source 1, and voltages obtained by the resistors R1 to R5 are used as a liquid crystal display unit to be described later. The voltage follower-connected operational amplifiers OP1 and OP2 for the low voltage side and operational amplifiers OP3 and OP4 for the low voltage side and the first voltage VM1 and the second voltage VM2 obtained by dividing the voltage of the voltage supply source 1 into three are generated. , Resistors R8, R9, R10 for maintaining, transistors Tn1, Tn2, Tp1, and capacitors C11, C12.
[0028]
The voltage obtained from the voltage supply source 1 is divided by resistors R1 to R5 connected in series, and the divided voltage is input to operational amplifiers OP1 to OP4 connected in voltage follower to output voltages V1 to V4. . These four voltage levels and the voltage of the voltage supply source 1 itself, V0 and V5, are a total of six levels of voltages that drive the liquid crystal panel.
[0029]
Also in this example, V0 to V5 have a relationship of approximately V0−V1 = V1−V2 = V3−V4 = V4−V5, and V0−V1 is about 1 to 1, although it depends on the threshold voltage and driving duty of the liquid crystal. About 2V, V0-V5 is about 10-40V.
[0030]
The transistor Tn1 and the capacitor C11 are means for holding the first voltage VM1 obtained by the resistors R8, R9, and R10 in a predetermined range, and the capacitor C11 is inserted between the VM1 and V5.
[0031]
Depending on the type of operational amplifier, VM1 should be lower than V2 by about 2V or more in order for the operational amplifiers OP1 and OP2 to operate normally, and the ratio of the resistance values of R8, R9, and R10 so that the voltage is close to V2. Should be set.
[0032]
The transistors Tn2, Tp1 and the capacitor C12 are means for holding the second voltage VM2 obtained by the resistors R8, R9, R10 in a predetermined range, and the capacitor C12 is inserted between the VM2 and V5. In order for the operational amplifiers OP3 and OP4 to operate normally, the VM2 should be higher than the V3 by about 2V or more, and the ratio of the resistance values of the R8, R9, and R10 should be set so as to be a voltage close to the V3.
[0033]
With the above configuration, the power consumption of the operational amplifier is proportional to the magnitude of the voltage between the power supply terminals, so that the power consumption of the operational amplifier is smaller than in the past. Then, the reduced power consumption is consumed in the transistor Tn2.
[0034]
Thus, according to the circuit configuration of the present invention, the voltage between the power supply terminals of the operational amplifier can be reduced without any loss of the effect of reducing the power consumption of the conventional liquid crystal driving voltage generating circuit. The power consumption of the operational amplifier is reduced by using the transistor Tn2 as a part of the power consumption generated by the low-voltage operational amplifier and the low-voltage operational amplifier, and the liquid crystal drive voltage generation circuit is used in a higher temperature environment. Can do.
[0035]
If the voltage of VM1 is made high and the voltage of VM2 is made too low, the power consumption of the operational amplifier is certainly reduced, but on the other hand, the power consumption at Tn2 becomes too large, thereby allowing the transistor tolerance called collector loss. It exceeds the power consumption that can be done. Similarly to the operational amplifier, since the allowable collector loss is small when the ambient temperature becomes high, the size of VM1 and VM2 may be determined in accordance with the allowable loss of the operational amplifier to be used and the collector loss of the transistor.
[0036]
According to an experiment conducted by the present inventor, a μPC358G2 made by NEC was used as an operational amplifier, a ROHM 2SC2412K was used for transistors Tn1 and Tn2, and a 7.7 ″ diagonal liquid crystal using 2SA1037AK for Tp1. When the display device is displayed in a checkerboard pattern, when the power (loss) consumed by the high-voltage side and low-voltage side operational amplifiers in the conventional configuration is 50% and viewed as 100%, R8 to By adjusting the ratio of R10 and increasing VM1 and decreasing VM2, the voltage between the power supply terminals of the operational amplifier is reduced. As a result, the loss of the operational amplifier is reduced by 17% from the conventional 50% to 33%. The loss of the operational amplifier on the voltage side and the low-voltage side is 33%, and both are 66%. Loss 17% × 2 = 34% is consumed by the transistor Tn2.
[0037]
Thus, the power consumption is 34%, and the power consumption of the operational amplifier can be reduced without changing the power consumption of the entire liquid crystal driving voltage generation circuit, which is 100% in total. In this way, by adjusting the ratio of the resistance values of R8 to R10, VM1 is increased and VM2 is decreased, so that the voltage between the power supply terminals of the high-voltage side and low-voltage side operational amplifiers is reduced, thereby causing a loss. Get smaller.
[0038]
As described above, the power consumed in two places of the high-voltage side and low-voltage side operational amplifiers in the past is partially consumed in the transistor Tn2 in the present invention, thereby reducing the power consumption of the operational amplifier. In addition, the liquid crystal driving voltage generation circuit can be used in a higher temperature environment.
[0039]
In addition, since the voltage between the power supply terminals of the operational amplifier becomes small, an inexpensive operational amplifier with a low voltage rating between the power supply terminals can be used.
[0040]
(Example 2)
FIG. 2 shows another liquid crystal driving voltage generating circuit of the present invention.
[0041]
The liquid crystal driving voltage generation circuit of this example has the same configuration except that a resistor R11 is inserted between the emitter of Tn1 and the collector of Tn2 in FIG.
[0042]
By inserting the resistor R11 in this way, the power consumption in the transistor Tn2 can also be borne by the resistor, and as a result, the VM1 is higher and the VM2 is higher than the voltage generation circuit for driving a liquid crystal of (Example 1). Can be set low.
[0043]
According to experiments conducted by the present inventor, when R11 (820Ω) is further added to the circuit shown in the example of (Example 1), 17% × 2 = 34% reduced by the operational amplifier is reduced to the transistor. Not only Tn2 but also the resistor R11 is loaded, that is, by adding the resistor R11, 28.2% of the 34% is the resistor R11, and the remaining 34-28.2 = 5.8% is the transistor. Tn2 is consumed.
[0044]
Therefore, the loss of the operational amplifier is reduced by about 17% compared to the conventional case, and the power consumption of the transistor Tn2 is 5.8% and the power consumption of the R11 is 28.2 without changing to 33%, which is 33%. The power consumption of the transistor can be reduced without changing the total of 100% and 100%.
[0045]
Thus, in this example, the power consumption of the transistor Tn2 can be reduced as compared with the circuit of (Example 1), whereby VM1 can be set higher and VM2 can be set lower, and as a result, from (Example 1). The voltage generation circuit for driving a liquid crystal can be used in a high temperature environment, and an operational amplifier with a lower rated voltage between the power supply terminals can be used.
[0046]
Next, liquid crystal display devices using the voltage generation circuit for driving a liquid crystal according to the present invention will be described in (Example 3) to (Example 5).
[0047]
(Example 3)
FIG. 3 shows an outline of a liquid crystal display device for time-division driving by the liquid crystal driving voltage generation circuit of the present invention, and FIG. 4 shows a cross section of the liquid crystal panel when a transmissive color type liquid crystal panel is used as the liquid crystal panel. The figure is shown.
[0048]
First, in the liquid crystal display device 5 shown in FIG. 3, reference numeral 4 denotes a liquid crystal panel and a drive circuit such as a driver IC for driving the liquid crystal panel.
[0049]
Reference numeral 3 denotes a voltage generation circuit for driving a liquid crystal according to the present invention. SGN is a signal for controlling the drive circuit, display data, etc. VDD and VSS are power sources for driving logic, and these are supplied from outside the liquid crystal display device.
[0050]
A booster circuit 2 generates VEE from VDD and VSS and supplies VEE to the voltage generation circuit 3 for driving the liquid crystal. However, this is not necessarily provided in the liquid crystal display device, and VEE is supplied from the outside. It may be.
[0051]
Next, the transmissive color type liquid crystal panel shown in FIG. 4 will be described. This figure is a cross-sectional view thereof, and is a structure in which the glass scanning substrate 6 as the one substrate and the glass signal substrate 7 as the other substrate are bonded together by a seal portion 8. A liquid crystal layer 9 is enclosed in a region surrounded by 8. The seal part 8 is made of a thermosetting resin such as epoxy, acrylic or silicone.
[0052]
In such a structure, the scanning-side substrate 6 and the signal-side substrate 7 are bonded via a sealant, and are further aligned to provide a space, and the sealant is heated and cured to form the seal portion 8.
[0053]
When providing such a space, non-conductive spacers 10 made of resinous spheres are dispersed and distributed between the scanning side substrate 6 and the signal side substrate 7, thereby keeping the distance between the substrates constant and liquid crystal inside the liquid crystal. Layer 9 is encapsulated.
[0054]
A plurality of signal electrodes 11 as electrode patterns arranged in the other direction are arranged in parallel on the signal substrate 7, and the arrangement pattern extends to the outside of the seal portion 8.
[0055]
A color filter 12 is formed on the scanning side substrate 6, an overcoat 13 is formed thereon, and a plurality of scanning electrodes 14 as electrode patterns arranged in the one direction are arranged in parallel thereon, The arrangement pattern extends to the outside of the seal portion 8.
[0056]
The color filter 12 is coated with a color resin solution of each color in which red (R), green (G), and blue (B) colorants such as dyes and pigments are uniformly dispersed on a transparent resin and the like, and is patterned by a photolithography method. Formed by a dispersion method or the like.
[0057]
The overcoat 13 is made of a transparent resin for protecting the color filter 12 and preventing elution of the coloring material into the liquid crystal layer 9.
[0058]
The signal electrode 11 and the scanning electrode 14 are arranged so as to be orthogonal to each other, and a region where these intersect is a rectangular display region. The signal electrode 11 and the scanning electrode 14 are made of ITO (Indium Tin Oxide) or the like. An alignment film 15 made of polyimide resin is coated on the signal electrode 11 and the scanning electrode 14.
[0059]
A liquid crystal driving driver IC is connected to the signal electrode 11 and the scanning electrode 14 outside the seal portion 8, thereby driving the liquid crystal panel.
[0060]
An optical compensation phase difference plate 16 and a polarizing plate 17 are disposed outside the scanning side substrate 6 and the signal side substrate 7, and a backlight system 18 is disposed on the scanning side substrate side of the liquid crystal panel. In the transmissive color liquid crystal panel, light from the backlight system 18 passes and is blocked by turning on and off the pixels in the display area, thereby displaying.
[0061]
Thus, in the liquid crystal display device 5 configured as described above, the power consumption of the operational amplifier can be reduced by using the liquid crystal drive voltage generation circuit of the present invention in the liquid crystal drive voltage generation circuit 3, so that the liquid crystal display device is more peripheral. Can be used in high temperature environments.
[0062]
(Example 4)
In this example, a transflective color type liquid crystal panel is used in place of the transmissive color type liquid crystal panel for the liquid crystal panel used in the liquid crystal display device 5 of FIG.
[0063]
FIG. 5 is a sectional view of the transflective color type liquid crystal panel. In addition, the same code | symbol is attached | subjected to the same location as FIG.
[0064]
In this liquid crystal panel, a semi-transmissive film 19 is formed under the color filter 12, and other than that, there is no particular difference from the transmissive type.
[0065]
The semi-transmissive film 19 is made of, for example, aluminum or a dielectric having a thickness of about 100 to 200 angstroms.
[0066]
The transflective LCD panel eliminates the loss of visibility under strong light such as sunlight in the transmissive panel by reflecting sunlight, and the backlight system is used even in dark places. It can be displayed by lighting.
[0067]
Thus, also in the liquid crystal display device 5 having the above-described configuration of the present example, the power consumption of the operational amplifier can be reduced by using the liquid crystal driving voltage generating circuit of the present invention for the liquid crystal driving voltage generating circuit 3. The liquid crystal display device can be used in an environment with a higher ambient temperature.
[0068]
(Example 5)
In this example, a case where a reflective color type liquid crystal panel is used for the liquid crystal panel of the liquid crystal display device 5 of FIG. 3 is shown, and FIG. 6 is a cross-sectional view of the liquid crystal panel.
[0069]
The reflective film 20 is formed under the color filter 12 and there is no difference from the transmissive type except that there is no retardation plate or polarizing plate on the backlight system and the scanning side substrate side. The reflective film 20 is made of aluminum of about 1000 angstroms, for example.
[0070]
Since the reflection type liquid crystal panel does not have a backlight system, a light source having a certain intensity is required, but since the power for the backlight system is not required, the power of the entire liquid crystal display device can be reduced.
[0071]
Thus, also in this example, in the liquid crystal display device 5 having the above-described configuration, the power consumption of the operational amplifier can be reduced by using the liquid crystal driving voltage generating circuit of the present invention for the liquid crystal driving voltage generating circuit 3, thereby reducing the liquid crystal display. The device can be used in a higher ambient temperature environment.
[0072]
It should be noted that the present invention is not limited to the above embodiment, and various changes and improvements can be made without departing from the scope of the present invention.
[0073]
For example, the liquid crystal panel of the liquid crystal display device 5 of FIG. 3 may be a monochrome type, and a color filter, a reflective film, and a semi-transmissive film may be provided on the signal side substrate.
[0074]
【The invention's effect】
As described above, according to the voltage generation circuit for driving a liquid crystal according to the present invention, it is possible to reduce the power consumption of the voltage generation circuit for driving a liquid crystal and to use an inexpensive operational amplifier having a low voltage rating between power supply terminals. Further, heat generation due to power consumption in the operational amplifier can be reduced, and the liquid crystal display device can be driven in an environment with a higher ambient temperature.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a voltage generation circuit for driving a liquid crystal according to the present invention.
FIG. 2 is a circuit diagram showing another liquid crystal driving voltage generating circuit of the present invention.
FIG. 3 is an explanatory diagram showing an operating state of a liquid crystal driving voltage generation circuit in the liquid crystal display device of the present invention.
FIG. 4 is a cross-sectional view of a transmissive color liquid crystal panel used in the liquid crystal display device of the present invention.
FIG. 5 is a cross-sectional view of a transflective color liquid crystal panel used in the liquid crystal display device of the present invention.
FIG. 6 is a cross-sectional view of a reflective color liquid crystal panel used in the liquid crystal display device of the present invention.
FIG. 7 is a waveform diagram showing an alternating voltage applied to a liquid crystal panel.
FIG. 8 is a circuit diagram showing a conventional liquid crystal driving voltage generation circuit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Voltage supply source 2 ... Booster circuit 3 ... Liquid crystal drive power supply circuit 4 ... Liquid crystal panel and liquid crystal drive circuit 5 ... Liquid crystal display device 6 ... Scanning side substrate 7 ... Signal side substrate 8 ... Seal part 9 ... Liquid crystal layer 10 ... Spacer 11 ... Signal electrode 12 ... Color filter 13 ... Overcoat 14 ... Scanning electrode 15 ... Alignment film 16 ... Phase difference plate 17 ... Polarizing plate 18 ... Backlight system 19 ... Semi-transmissive film 20 ... Reflection films R1-R11 ... Resistance OP1 ~ OP4 ... operational amplifiers C1 to C5, C11, C12 ... capacitors Tn, Tn1, Tn2, Tp, Tp1 ... transistors

Claims (2)

A liquid crystal drive in which a voltage obtained by dividing the voltage of the voltage supply source by a plurality of first voltage dividing resistors connected in series is supplied to the liquid crystal drive driver IC via each operational amplifier connected in voltage follower. In the voltage generator circuit
A capacitor that holds each of the first voltage and the second voltage obtained by dividing the voltage of the voltage supply source into three by a second voltage dividing resistor;
A first transistor to keep the first voltage in a predetermined range,
A second transistor that keeps the second voltage within a predetermined range ,
The first voltage is higher than the second voltage;
The negative power supply terminal of the operational amplifier on the high voltage side of the operational amplifier is connected to the first voltage, the positive power supply terminal of the operational amplifier on the low voltage side is connected to the second voltage,
A third transistor located between the first transistor and the second transistor and connected in series with the first transistor and the second transistor;
A voltage generation circuit for driving a liquid crystal , further comprising: a resistor positioned between the first transistor and the third transistor and connected in series with the first transistor and the third transistor .   One electrode having an electrode pattern arranged in one direction and an alignment film, and the other electrode having an electrode pattern arranged in the other direction and the other substrate having an alignment film are arranged opposite to each other via a liquid crystal layer. 2. A liquid crystal driving driver IC for driving display of the liquid crystal display panel and a liquid crystal driving voltage generating circuit according to claim 1 provided for a liquid crystal display panel having a display area by intersecting patterns. Simple matrix liquid crystal display device.

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