JP2005250034A - Electrooptical device, driving method of electrooptical device and electronic appliance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more effectively suppress after-image display when an electrooptical device is powered OFF. <P>SOLUTION: During normal drive before timing t1, a gradation voltage corresponding to a display gradation of a pixel is selected within a specified output range and outputted to a data line. Consequently, the potential difference between a pixel electrode supplied with the gradation voltage through the data line and a counter electrode applied with a constant voltage V1 is variably set. When the power source of the electrooptical device is turned OFF, a center voltage Vcntr is selected in off-sequence periods t1 to t3 before the power source is turned OFF, and outputted to the data line. This center voltage Vcntr is positioned in the center of an output range of gradation voltages Vmin to Vmax and higher than a 1st voltage V1. Consequently, the voltage applied to the pixel electrode is set equivalent to the voltage V1 applied to the counter electrode. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electro-optical device, a driving method of the electro-optical device, and an electronic apparatus, and more particularly to an off sequence performed prior to power-off of the electro-optical device.

Patent Document 1 discloses an off sequence that is performed prior to power-off in order to suppress an afterimage that occurs when the liquid crystal display device is powered off. In this off sequence, the data line driving circuit (source driver) selects and selects the same voltage (for example, 0 V) as the applied voltage of the counter electrode (common electrode) regardless of the gradation to be originally displayed. The voltage is output to the data line. Thereby, the potential difference between the pixel electrode and the common electrode is minimized, and the residual charge of the liquid crystal layer sandwiched between them is also reduced.
JP 2003-50565 A

  However, in the above-described prior art, the influence of the push-down of the transistor existing in the path until the output voltage from the data line driving circuit is supplied to the pixel electrode is not taken into consideration. Here, “pushdown” refers to a voltage change (punch-through voltage) due to parasitic capacitance between the gate and drain of a transistor. When the output voltage of the data line driving circuit is made the same as the voltage applied to the counter electrode, the voltage actually applied to the pixel electrode via the data line is lower than the output voltage by the amount of pushdown. For this reason, a potential difference corresponding to a push-down occurs between the pixel electrode and the counter electrode, and charges remain in the liquid crystal layer. Even if the power is turned off in such a residual state, not only the afterimage display cannot be completely eliminated, but there is also a problem that the direct current is applied to the liquid crystal layer for a long time and the deterioration thereof is accelerated.

  The present invention has been made in view of such circumstances, and an object thereof is to more effectively suppress afterimage display when the electro-optical device is powered off.

  Another object of the present invention is to more effectively suppress deterioration of an electro-optical layer typified by a liquid crystal layer and improve the life of the electro-optical device.

  In order to solve this problem, the first and second aspects of the invention provide an electro-optical device having a plurality of scanning lines, a plurality of data lines, a plurality of pixels, a scanning line driving circuit, and a data line driving circuit. I will provide a. The plurality of pixels are provided corresponding to the intersection of the plurality of scanning lines and the plurality of data lines. Each of the pixels includes an electro-optic layer sandwiched between one electrode and the other electrode. The scanning line driving circuit sequentially selects a plurality of scanning lines. The data line driving circuit selects a voltage to be supplied to the plurality of data lines and cooperates with the scanning line driving circuit to supply the selected voltage to one electrode through the data line. In such a configuration, the first invention relates to a so-called common DC drive off sequence for keeping the applied voltage of the counter electrode constant, and the second invention is a so-called common AC that variably sets the applied voltage of the counter electrode. It relates to the driving off sequence.

  That is, in the first invention, the data line driving circuit selects and outputs a gradation voltage corresponding to the display gradation of the pixel within a predetermined output range during normal driving. As a result, the potential difference between one electrode to which the gradation voltage is supplied and the other electrode to which the constant first voltage is applied is variably set. When the electro-optic device is turned off, the data line driving circuit selects and outputs the center voltage in an off sequence prior to turning off the power. This center voltage is located at the center of the output range of the gradation voltage and is higher than the first voltage. Thereby, the voltage applied to one electrode is set to correspond to the first voltage applied to the other electrode. Here, the center voltage is preferably higher than the first voltage by a push-down amount of a transistor existing in a path until the voltage selected by the data line driver circuit is supplied to one electrode.

  In the second invention, the data line driving circuit selects and outputs a gradation voltage corresponding to the display gradation of the pixel within a predetermined output range during normal driving. Thereby, the potential difference between one electrode to which the gradation voltage is supplied and the other electrode to which the first voltage and the second voltage are alternately applied is variably set. When the electro-optic device is turned off, the data line driving circuit selects and outputs the center voltage in an off sequence prior to turning off the power. This center voltage is a voltage higher than the third voltage located at the center of the output range of the gradation voltage and located at the center between the first voltage and the second voltage. Thereby, the voltage applied to one electrode is set to be equivalent to the third voltage applied to the other electrode. Here, the center voltage is preferably higher than the third voltage by a push-down amount of a transistor existing in a path until the voltage selected by the data line driver circuit is supplied to one electrode.

  According to the first or second invention, in the off sequence, the applied voltage of one electrode becomes equivalent to the applied voltage of the other electrode, and the residual charge of the electro-optic layer is substantially absent. If the power is turned off in the absence of residual charges, the occurrence of afterimages can be effectively suppressed. In addition, since there is no residual charge, it is possible to prevent a state where direct current is applied to the electro-optic layer for a long time after the power is turned off. As a result, deterioration of the electro-optic layer can be suppressed, and the life of the electro-optic device can be improved.

  In the off sequence of the first or second invention, the scanning line driving circuit sequentially selects a plurality of scanning lines, and the data line driving circuit waits until all selection of at least the plurality of scanning lines is completed. Meanwhile, it is preferable to select the center voltage as the voltage supplied to the plurality of data lines. Thereby, the above-described effect can be obtained uniformly over the entire display unit constituted by a plurality of pixels.

  In the first or second invention, the power-off is present in the path after the end of the off-sequence and until the voltage selected by the data line driving circuit is supplied to one of the electrodes. This is preferably performed after the transistor is turned off. As a result, the residual charge of the electro-optic layer is more surely absent, so that the above-described effect becomes more remarkable.

  Furthermore, a third invention provides an electronic apparatus in which the electro-optical device according to the first or second invention is mounted. Thereby, the product value of the electronic device can be further increased, and the product appeal of the electronic device in the market can be improved.

  On the other hand, the fourth or fifth invention has a plurality of pixels provided corresponding to intersections of the plurality of scanning lines and the plurality of data lines, and each of the pixels includes one electrode and the other electrode. The present invention relates to a driving method of an electro-optical device including an electro-optical layer sandwiched between the two. The fourth invention relates to a common DC drive off sequence, and the fifth invention relates to a common AC drive off sequence.

  In other words, the driving method according to the fourth aspect of the invention provides a gradation voltage output range that is variably set according to the display gradation of the pixel in a state where the constant first voltage is applied to the other electrode. A first step of supplying a center voltage higher than the first voltage to the plurality of data lines; and a plurality of scanning lines in a state where the center voltage is supplied to the plurality of data lines. After the second step of setting the voltage applied to one electrode to be equivalent to the first voltage applied to the other electrode by sequentially selecting, and selecting all of the plurality of scanning lines, And a third step of turning off the power of the electro-optical device.

  In the driving method according to the fifth aspect of the present invention, the third voltage positioned at the center of the first voltage and the second voltage that are alternately set during normal driving is applied to the other electrode. A first step of supplying a plurality of data lines with a center voltage higher than the third voltage and positioned at the center of the output range of the gradation voltage variably set according to the display gradation of the pixel; In the state where the center voltage is supplied to the plurality of data lines, by sequentially selecting the plurality of scanning lines, the voltage applied to one electrode is equivalent to the third voltage applied to the other electrode. A second step of setting, and a third step of turning off the power of the electro-optical device after selection of all of the plurality of scanning lines is completed.

  According to the 4th or 5th invention, the same effect as the 1st or 2nd invention mentioned above can be acquired.

(First embodiment)
FIG. 1 is a block diagram of the electro-optical device according to the present embodiment. The display unit 1 is an active matrix display panel that drives an electro-optical element by, for example, a TFT (Thin Film Transistor). In the display unit 1, a group of pixels corresponding to m dots × n lines are arranged in a matrix (in a two-dimensional plane). The display unit 1 is provided with scanning line groups Y1 to Yn each extending in the horizontal direction and data line groups X1 to Xm each extending in the vertical direction. Pixel 2 is arranged corresponding to the above.

  FIG. 2 is an equivalent circuit diagram of the pixel 2 using a liquid crystal layer as an example. One pixel 2 includes a TFT 21 that is a switching element, a liquid crystal capacitor 22, and a storage capacitor 23. The source of the TFT 21 is connected to one data line X, and its gate is connected to one scanning line Y. Regarding the pixels 2 arranged in the same column, the sources of the respective TFTs 21 are connected to the same data line X. For the pixels 2 arranged in the same row, the gates of the respective TFTs 21 are connected to the same scanning line Y. The drain of the TFT 21 is commonly connected to a liquid crystal capacitor 22 and a storage capacitor 23 provided in parallel. The liquid crystal capacitor 22 includes a pixel electrode 22a, a counter electrode 22b to which a voltage Vcom is applied, and a liquid crystal layer sandwiched between these electrodes 22a and 22b. The storage capacitor 23 is formed between the pixel electrode 22a and a common capacitor electrode (not shown), and is supplied with a voltage Vcs. The storage capacitor 23 is provided in order to suppress leakage of charges accumulated in the liquid crystal, but may not be provided if this point is not taken into consideration. On the other hand, a voltage is supplied to and applied to the pixel electrode 22a via the data line X and the TFT 21. As a result, the liquid crystal capacitor 22 and the like are charged and discharged according to the potential difference between the pair of electrodes 22a and 22b, and the transmittance of the liquid crystal layer is set.

  The driving of the pixel 2 is performed by AC driving in which the voltage polarity is inverted every predetermined period in order to improve the life of the liquid crystal layer. This voltage polarity is defined based on the direction of the electric field acting on the liquid crystal layer, in other words, based on the forward and reverse of the voltage applied to the liquid crystal layer. In the present embodiment, common DC driving, which is one type of AC driving, that is, the voltage Vcom (and Vcs) applied to the counter electrode 22b is kept constant, and the polarity of the voltage applied to the pixel electrode 22a is set to the voltage Vcom. A driving method that periodically inverts the signal is used.

  The control circuit 5 outputs internal signals DY, CLY, DX, CLX and the like shown in FIG. 3 based on a vertical synchronization signal Vs, a horizontal synchronization signal Hs, a dot clock signal DCLK, and the like input from a host device (not shown). The scanning line driving circuit 3 and the data line driving circuit 4 are synchronously controlled. Under this synchronization control, these circuits 3 and 4 perform display control of the display unit 1 in cooperation with each other.

  The scanning line driving circuit 3 is mainly composed of a shift register, an output circuit, and the like, and performs line sequential scanning for sequentially selecting the scanning lines Y1 to Yn in a predetermined order. Specifically, the start pulse DY supplied at the beginning of one frame (1F) is transferred according to the clock signal CLY, thereby setting the voltage level of the scanning signal output to each of the scanning lines Y1 to Yn. . The scanning signal takes a binary level, the scanning line Y corresponding to the pixel row to which data is to be written is set to a high voltage level (hereinafter referred to as “H level”), and the other scanning lines Y It is set to a low voltage level (hereinafter referred to as “L level”). A period during which one scanning line Y is maintained at the H level, that is, a period during which the scanning line Y is selected is one horizontal scanning period (1H). Along with the sequential selection of the scanning lines Y1 to Yn, in 1F, pixel rows to which data is to be written are sequentially selected every 1H.

  The data line driving circuit 4 is mainly composed of a shift register, a line latch circuit, a DAC, etc., and selects a voltage to be supplied to the data lines X1 to Xm based on a voltage group prepared in advance. Is output. As a basic operation of the data line driving circuit 4, simultaneous output of data for a pixel row to which data is to be written in 1H this time and dot-sequential latching of data relating to a pixel row to be written in the next 1H are simultaneously performed. Done. That is, the start pulse DX output at the beginning of 1H is transferred in accordance with the clock signal CLX, whereby m data supplied serially from the upper circuit are sequentially latched at 1H. In the next 1H, the latched m pieces of data are converted into analog voltage data in the DAC, and are simultaneously output in parallel to the corresponding data lines X1 to Xm.

  FIG. 3 is an operation timing chart of common DC driving according to the present embodiment. In the figure, the thick solid line indicates the waveform of the voltage Vx output to the data line X with the data line driving circuit 4. However, it should be noted that the shape of the waveform before the timing t1 is merely an example, and various shapes are actually obtained depending on the image to be displayed. The thick dotted line is the waveform of the voltage Vcom applied to the counter electrode 22b of the pixel 2. In the case of common DC driving, the applied voltage Vcom of the counter electrode 22b is maintained at a constant value (that is, V1) before the timing t1 when the normal driving is performed or regardless of the period t1 to t2 during which the off sequence is performed.

  Before the timing t1 when the normal driving is performed, the scanning line driving circuit 3 performs the line sequential scanning of the scanning lines Y1 to Yn, and the data line driving circuit 4 cooperates with the scanning line driving circuit 3 to perform the pixel 2 Select and output the gradation voltage corresponding to the display gradation. As a result, the potential difference between the pixel electrode 22a to which the gradation voltage is supplied via the data line X and the counter electrode 22b to which the voltage Vcom is applied is variably set, and the gradation of the pixel 2 is set. . Here, the gradation voltage is selected within an output range defined by a preset upper limit value Vmax and lower limit value Vmin. Further, since the applied voltage Vcom of the counter electrode 22b is a constant value V1, the driving polarity of the frame is set depending on the gradation voltage. In the example shown in the figure, in the odd-numbered frame, the gradation voltage is selected within the range higher than the voltage value V1 among the output ranges Vmin to Vmax, and this is output to the data line X (positive drive). . On the other hand, in the even-numbered frame, the gradation voltage is selected within a range lower than the voltage value V1 among the output ranges Vmin to Vmax, and this is output to the data line X (negative polarity driving). Regarding the output range Vmin to Vmax of the gradation voltage, the center voltage Vcntr located at the center is set higher than V1 which is the applied voltage Vcom of the counter electrode 22b. The reason why the center voltage Vcntr is set high is that the influence of push-down of transistors existing in the path until the voltage selected by the data line driving circuit 4 is supplied to the pixel electrode 22a is taken into consideration. In general, the gradation voltage is set so that the direct-current application to the liquid crystal layer is as small as possible in order to prevent deterioration of the liquid crystal layer or to suppress deterioration in image quality such as flicker. In other words, the relationship between the applied voltage Vcom V1 of the counter electrode 22b and the center voltage Vcntr is set such that the former is lower than the latter by a push-down amount. As a transistor that should be considered for such pushdown, for example, the TFT 21 (pixel transistor) included in the pixel 2 shown in FIG. 2 can be cited. In addition, a part of the data line driving circuit 4 is configured. The sample hold transistor provided in the back | latter stage of DAC to perform is mentioned. Therefore, if the voltage drop ΔV due to such push-down is specified in advance through experiments, simulations, etc., and a difference of ΔV is set between the voltage V1 and the center voltage Vcntr, ΔV can be substantially offset. . From this point of view, the output range Vmin to Vmax of the gradation voltage is offset to the high voltage side as a whole by ΔV with respect to V1.

  When the electro-optical device is turned off by an instruction from a host device (not shown), the power is not turned off suddenly, but an off sequence is performed prior to this. In the first half period t1 to t2 of the off sequence, the scanning line driving circuit 3 performs the line sequential scanning of the scanning lines Y1 to Yn for a period of 1F or more, that is, at least until all selection of the scanning lines Y1 to Yn is completed. I do. At the same time, the data line driving circuit 4 selects and outputs the center voltage Vcntr regardless of the display gradation of the pixel 2. Further, the applied voltage Vcom of the counter electrode 22b is maintained at V1. In this case, the voltage applied to the pixel electrode 22a is reduced by ΔV due to the push-down of the transistor existing in the voltage supply path up to the pixel electrode 22a, and thus becomes (Vcntr−ΔV). This value (Vcntr−ΔV) corresponds to V1 that is the applied voltage Vcom of the counter electrode 22b. Therefore, there is substantially no potential difference between the pair of electrodes 22a and 22b, and the charge in the liquid crystal layer is almost completely lost (writing substantially 0 V). Further, in the second half period t2 to t3 of the off sequence, the transistor existing in the voltage supply path, for example, the TFT 21 in the pixel 2 or the sample hold transistor is turned off in order to more surely eliminate the residual charge in the liquid crystal layer ( Ready off). At this time, input of the start pulses DX and DY is stopped, but the clock signals CLX and CLY are continuously input. Then, after these transistors are turned off, the electro-optical device is turned off.

  As described above, according to the present embodiment, the residual charge of the liquid crystal layer can be remarkably reduced as compared with the conventional technique described above. In the prior art, the voltage selected and output by the data line driving circuit is the same as the voltage applied to the counter electrode. Therefore, the voltage applied to the pixel electrode does not coincide with the voltage applied to the counter electrode, and is actually lower than the voltage applied to the counter electrode by a voltage drop ΔV due to pushdown. As a result, when the power is turned off, charges corresponding to the voltage drop ΔV remain in the liquid crystal layer. On the other hand, in the present embodiment, the voltage selected and output by the data line driving circuit 4 is not the same as the applied voltage Vcom (= V1) of the counter electrode 22b, but is the center voltage Vcntr higher than this by ΔV. . Accordingly, the voltage applied to the pixel electrode 22a is a value that is decreased from the center voltage Vcntr by the push-down voltage change amount ΔV, and consequently coincides with V1 that is the applied voltage Vcom of the counter electrode 22b. Therefore, since the residual charge of the liquid crystal layer is not substantially present, it is possible to effectively suppress the occurrence of an afterimage when the power is turned off. At the same time, a state where a direct current is applied to the liquid crystal layer for a long time due to the residual charge can be prevented, so that the deterioration of the liquid crystal layer can be suppressed and the life of the electro-optical device can be improved.

  In the present embodiment, in the off sequence, the center voltage Vcntr is continuously selected as the voltage to be supplied to the data lines X1 to Xm at least until all the scanning lines Y1 to Yn are selected. Thereby, the above-described effects can be obtained uniformly over the entire display unit 1 including the plurality of pixels 2.

(Second Embodiment)
The present embodiment relates to an off sequence of so-called common AC driving (common descending driving) in which the applied voltage of the counter electrode 22b is variably set. The basic configuration of the electro-optical device and the pixel 2 is the same as that shown in FIGS.

  FIG. 4 is a timing chart of common AC driving according to the present embodiment. In the figure, the thick solid line indicates the waveform of the voltage Vx output to the data line X with the data line driving circuit 4, and the thick dotted line indicates the waveform of the voltage Vcom applied to the counter electrode 22 b of the pixel 2. In the case of common AC driving, the applied voltage Vcom of the counter electrode 22b is alternately set to two voltage values Vl and Vh in a predetermined cycle (for example, 1F) before the timing t1 when normal driving is performed (Vl <Vh). . In addition, in the period t1 to t2 during which the off sequence is performed, the applied voltage Vcom is set to a center voltage Vcntr ′ located at the center of these voltage values Vl and Vh.

  Before the timing t1 when normal driving is performed, the scanning line driving circuit 3 performs line sequential scanning of the scanning lines Y1 to Yn, and the data line driving circuit 4 applies a gradation voltage corresponding to the display gradation of the pixel 2. Select and output within the specified output range Vmin to Vmax. As a result, the potential difference between the pixel electrode 22a to which the gradation voltage is supplied via the data line X and the counter electrode 22b to which the voltage Vcom is applied is variably set, and the gradation of the pixel 2 is set. . Further, the applied voltage Vcom of the counter electrode 22b takes either Vl or Vh, and the drive polarity of the frame is set depending on the voltage Vcom. In the example shown in the figure, in the odd-numbered frame, the low voltage value Vl is set as the applied voltage Vcom of the counter electrode 22b, and all gradation voltages are set on the higher voltage side than Vl (positive drive). . On the other hand, in the even-numbered frame, the high voltage value Vh is set as the applied voltage Vcom of the counter electrode 22b, and all gradation voltages are set to a lower voltage side than Vh (negative polarity driving). Note that the center voltage Vcntr positioned at the center of the output range Vmin to Vmax of the gradation voltage takes into account the above-described pushdown voltage drop ΔV and the center voltage Vcntr positioned at the center of the two voltage values Vl and Vh. Is set higher than '.

  When the electro-optical device is turned off, an off sequence is performed prior to turning off the power. In the first half period t1 to t2 of the off sequence, the scanning line driving circuit 3 performs the scanning lines Y1 to Yn for a period of 1F or more, in other words, at least until all selection of the scanning lines Y1 to Yn is completed. Sequential scanning is performed. At the same time, the data line driving circuit 4 selects and outputs the center voltage Vcntr regardless of the display gradation of the pixel 2. Further, the applied voltage Vcom of the counter electrode 22b is maintained at the center voltage Vcentr ′ located between the two voltage values Vl and Vh. In this case, the voltage applied to the pixel electrode 22a is reduced by ΔV due to the push-down of the transistor existing in the voltage supply path up to the pixel electrode 22a, and thus becomes (Vcntr−ΔV). This value (Vcntr−ΔV) corresponds to Vcntr ′ which is the applied voltage Vcom of the counter electrode 22b. Therefore, there is substantially no potential difference between the pair of electrodes 22a and 22b, and the charge in the liquid crystal layer disappears almost completely. On the other hand, in the latter half period t2 to t3 in which the preparation for turning off is performed following such a substantial 0V writing, the transistor existing in the voltage supply path is turned off in order to more surely eliminate the residual charge of the liquid crystal layer. At this time, input of the start pulses DX and DY is stopped, but the clock signals CLX and CLY are continuously input. Then, after these transistors are turned off, the electro-optical device is turned off.

  As described above, according to the present embodiment, in the common AC drive, there is substantially no residual charge when the power is turned off, so that the same effect as in the first embodiment can be obtained.

  The electro-optical device according to each embodiment described above can be mounted on various electronic devices including, for example, a television, a projector, a mobile phone, a mobile terminal, a mobile computer, a personal computer, and the like. FIG. 5 is a perspective view of the cellular phone 10 on which the electro-optical device according to each embodiment described above is mounted as an example. The mobile phone 10 includes the above-described display unit 1 together with the earpiece 12 and the mouthpiece 13 in addition to the plurality of operation buttons 11. When the above-described electro-optical device is mounted on these electronic devices, the commercial value of the electronic devices can be further increased, and the product appeal of electronic devices in the market can be improved.

Block diagram of electro-optical device Equivalent circuit diagram of pixel using liquid crystal Common DC drive timing chart Common AC drive timing chart Perspective view of a mobile phone equipped with an electro-optical device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display part 2 Pixel 3 Scan line drive circuit 4 Data line drive circuit 5 Control circuit

Claims (9)

In an electro-optical device,
A plurality of scan lines;
Multiple data lines,
A plurality of pixels including an electro-optic layer provided corresponding to the intersection of the plurality of scanning lines and the plurality of data lines and sandwiched between one electrode and the other electrode;
A scanning line driving circuit for sequentially selecting the plurality of scanning lines;
A data line driving circuit for selecting a voltage to be supplied to the plurality of data lines and for supplying the selected voltage to the one electrode via the data line in cooperation with the scanning line driving circuit; Have
The data line driving circuit includes:
During normal driving, by selecting a gradation voltage corresponding to the display gradation of the pixel within a predetermined output range, the one electrode to which the gradation voltage is supplied and a constant first voltage are applied. Set the potential difference between the other electrode to be variable,
When turning off the power of the electro-optical device, by selecting a center voltage that is located at the center of the output range and higher than the first voltage in an off sequence prior to turning off the power, An electro-optical device, wherein a voltage applied to one electrode is set to correspond to the first voltage applied to the other electrode.   The center voltage is higher than the first voltage by a push-down amount of a transistor existing in a path until a voltage selected by the data line driving circuit is supplied to the one electrode. The electro-optical device according to claim 1. In an electro-optical device,
A plurality of scan lines;
Multiple data lines,
A plurality of pixels including an electro-optic layer provided corresponding to the intersection of the plurality of scanning lines and the plurality of data lines and sandwiched between one electrode and the other electrode;
A scanning line driving circuit for sequentially selecting the plurality of scanning lines;
A data line driving circuit for selecting a voltage to be supplied to the plurality of data lines and for supplying the selected voltage to the one electrode via the data line in cooperation with the scanning line driving circuit; Have
The data line driving circuit includes:
During normal driving, by selecting a gradation voltage corresponding to the display gradation of the pixel within a predetermined output range, the one electrode to which the gradation voltage is supplied, the first voltage, and the second voltage A potential difference between the other electrode to which a voltage is applied alternately is set variably,
When turning off the power of the electro-optical device, it is located at the center of the output range and at the center of the first voltage and the second voltage in an off sequence prior to turning off the power. By selecting a center voltage higher than the third voltage, the voltage applied to the one electrode is set to be equivalent to the third voltage applied to the other electrode. apparatus.   The center voltage is higher than the third voltage by a push-down amount of a transistor existing in a path until a voltage selected by the data line driving circuit is supplied to the one electrode. The electro-optical device according to claim 3. In the off sequence,
The scanning line driving circuit sequentially selects the plurality of scanning lines,
The data line driving circuit selects the center voltage as a voltage to be supplied to the plurality of data lines until at least all selection of the plurality of scanning lines is completed. 3. The electro-optical device described in 3.   The power-off is performed after the end of the off-sequence and after turning off a transistor existing in a path until the voltage selected by the data line driving circuit is supplied to the one electrode. The electro-optical device according to claim 1, wherein   An electronic apparatus comprising the electro-optical device according to claim 1 mounted thereon. An electric device having a plurality of pixels provided corresponding to intersections of a plurality of scanning lines and a plurality of data lines, each of which includes an electro-optic layer sandwiched between one electrode and the other electrode In the driving method of the optical device,
In a state where a constant first voltage is applied to the other electrode, the first voltage is located at the center of the output range of the gradation voltage variably set according to the display gradation of the pixel, and the first A first step of supplying a center voltage higher than the voltage of the plurality of data lines;
In a state where the center voltage is supplied to the plurality of data lines, by sequentially selecting the plurality of scanning lines, a voltage applied to the one electrode via the data line is changed to the other electrode. A second step of setting a value corresponding to the first voltage applied to
And a third step of turning off the power supply of the electro-optical device after all of the plurality of scanning lines have been selected. An electric device having a plurality of pixels provided corresponding to intersections of a plurality of scanning lines and a plurality of data lines, each of which includes an electro-optic layer sandwiched between one electrode and the other electrode In the driving method of the optical device,
Variable according to the display gradation of the pixel, with the third voltage positioned at the center of the first voltage and the second voltage alternately set during normal driving being applied to the other electrode A first step of supplying a center voltage higher than the third voltage to the plurality of data lines, which is located at the center of the output range of the gradation voltage set to
In a state where the central voltage is supplied to the plurality of data lines, by sequentially selecting the plurality of scanning lines, a voltage applied to the one electrode is applied to the other electrode. A second step of setting a voltage equivalent to 3;
And a third step of turning off the power supply of the electro-optical device after all of the plurality of scanning lines have been selected.

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