Abstract: A shift register includes plural stages of flip-flops. The last-stage flip-flop Fn and the flip-flop Fn?1 that is the preceding flip-flop thereof are reset by inputting thereto an output signal from the last-stage flip-flop. A delaying means is provided, between an output terminal Q of the last-stage flip-flop for outputting the output signal and an input terminal R of the last-stage flip-flop for receiving the output signal, for delaying an input of the output signal to the input terminal R. The flip-flop Fn is reset at same time or after the preceding flip-flop Fn?1 is reset. With this arrangement, it is possible to prevent malfunctions of circuits due to a failure to reset the flip-flops.

Abstract: A signal line driving circuit includes a shift register having a plurality of shift circuits, each of which shifts a start pulse successively to the next stage, synchronizing with the timing of a clock signal. In this signal line driving circuit, shift pulses are outputted from an AND gate based on output pulses of two adjacent shift circuits. Meanwhile, a width specifying pulse for specifying a pulse width of the shift pulse is inputted via a transistor whose ON/OFF operation is controlled by the shift pulse. A logical operation circuit operates an AND of the shift pulse and the width specifying pulse and outputs the result of operation to a signal line. When the shift pulse is non-active, the transistor becomes OFF, which causes the signal line transmitting the width specifying pulse to be disconnected from the signal line driving circuit, thereby reducing a capacitive load of wiring.

Abstract: Before a potential of counter electrode is changed, a potential holding circuit fixedly holds potentials of data signal lines S during a non-selective period of scanning signal lines G. This prevents the potentials of the data signal lines S from being an undesirably large potential, which is caused by coupling capacitors between the counter electrode and each data signal line S, whereby it is possible to supply to the pixel capacitor an electric charge corresponding to a gradation to be displayed, by using the relatively low potentials of the data signal lines S. This lowers a power supply voltage of a data signal driving circuit SD, thus reducing the electric power consumption. In short, with this arrangement, a liquid crystal display device can perform an opposed AC drive for line-inversion drive, frame-inversion drive and the like, by low power supply voltage of the data signal line driving circuit SD, thereby reducing the electric power consumption.

Abstract: A signal line driving circuit includes a shift register having a plurality of shift circuits, each of which shifts a start pulse successively to the next stage, synchronizing with the timing of a clock signal. In this signal line driving circuit, shift pulses are outputted from an AND gate based on output pulses of two adjacent shift circuits. Meanwhile, a width specifying pulse for specifying a pulse width of the shift pulse is inputted via a transistor whose ON/OFF operation is controlled by the shift pulse. A logical operation circuit operates an AND of the shift pulse and the width specifying pulse and outputs the result of operation to a signal line. When the shift pulse is non-active, the transistor becomes OFF, which causes the signal line transmitting the width specifying pulse to be disconnected from the signal line driving circuit, thereby reducing a capacitive load of wiring.

Abstract: In a vertical retrace interval, a pre-charge potential or a signal potential is applied to each polarity for AC driving liquid crystal at least once each, so as to maintain fluctuations in pixel potential between the positive polarity side and the negative polarity side uniform, and minimum required potentials are supplied to the data signal line, thereby suppressing decrease in image quality without significantly increasing power consumption.

Abstract: The scanning signal line driving circuit sequentially carries out active driving with respect to each set of a certain number of scanning signal lines which are adjacent to each other in a vertical direction, and when carrying out an actual writing with respect to a first set of a certain number of pixel lines adjacent to each other in the vertical direction, carries out pre-charging with respect to a second set of the certain number of pixel lines to which the actual writing is carried out next with a potential of a same polarity as that of the first set of the certain number of pixel lines. In this manner, it is possible to provide a matrix image display device with no irregularities in display quality and is capable of matching the apparent vertical resolution of the device to that of the image source, when using an image signal of vertical resolution lower than the maximum physical vertical resolution of the device.

Abstract: The present invention includes: a shift register section, including multiple-stage flip-flops operating in synchronism with a clock signal, for switching a shift direction in accordance with an externally supplied direction instruct signal; a waveform change section for changing in waveform a signal output of one of the flip-flops which is in a first predetermined stage; and an inspection signal switching section for switching, in accordance with the direction instruct signal, an output between the signal output which has been changed in waveform in the waveform change section and a signal output of one of the flip-flops which is in a second predetermined stage.

Abstract: An image display device includes two data signal line drive circuits and two scan signal line drive circuits configured differently from each other. Different data signal line drive circuits and scan signal line drive circuit are compatible with different display formats. A display can be produced in the most suitable display format, and power consumption also can be reduced, by switch operating drive circuits according to the kind of input video and environmental conditions. Further, an image can be written over another image by writing video signals to signal lines with a time lag using a plurality of drive circuits; therefore, a superimposed display can be produced without externally processing the video signals. Thus, both a satisfactory image display and low power consumption can be achieved in an image display device.

Abstract: A driving device of a display device includes: a data signal line driving circuit, provided with a shift register having a level shifter for boosting a source clock signal so as to apply the source clock signal to a flip-flop, which causes a sampling circuit to directly sample a multi-gradation data signal based on each output from the shift register so as to output the multi-gradation data signal to each of a plurality of data signal lines; a control circuit for switching a full-screen display mode in which a whole of the display screen performs display and a partial-screen display mode in which only a part of the display screen performs time-sharing display; a data generating section for generating a constant voltage data writing signal made of a constant voltage; and a control circuit for outputting a selection signal for causing a nondisplay portion to directly sample the constant voltage data writing signal from the constant voltage data writing signal generation means so as to output the constant voltag

Abstract: A driving device of a display device includes: a data signal line driving circuit including a shift register which has (i) multiple stages of flip-flops each of which operates in synchronism with a source clock signal and (ii) a level shifter for boosting the source clock signal whose amplitude is smaller than a driving voltage of each of the flip-flops so as to apply the driving voltage to the flip-flop, said data signal line driving circuit causing a sampling circuit to sample the image display data signal based on an output from the shift register so as to output the image display data signal to the data signal line; and control means for causing a frequency of the source clock signal in case of displaying an image to be higher than a frequency of the source clock signal in case of normal display in which multi-gradation display is performed in a full-color mode.

Abstract: A plurality of scanning signal lines GLn divided into groups, and each group is made up of three scanning signal lines GLnR, GLnG and GLnB, and a plurality of pixels are divided into pixel blocks, and each pixel block is made up of three pixels PR (n, m), PG (n, m) and PB (n, m) respectively connected to the scanning signal lines GLnR, GLnG and GLnB. These pixels PR (n, m), PG (n, m) and PB (n, m) are connected to a common data signal line SLm. To the scanning signal lines GLnR, GLnG, GLnB, scanning pulses are sequentially outputted to the scanning signal lines GLnR, GLnG and GLnB from shift registers SRnR, SRnG and SRnB, and video signals for R, G and B are outputted to the data signal line SLm from a driver IC by time division.

Abstract: A potential of a data signal line S during a scanning period is charged to a substantially intermediate potential of a data signal at a corresponding frame. Thus, extremely large dispersion does not occur in a potential of each pixel capacitor with respect to a potential of the data signal line S, so that it is possible to restrict dispersion of a leak current flowing via an active element of each pixel. Thus, potential variation of a pixel PIX is reduced, so that it is possible to improve display quality during a non-scanning period. That is, in an active-matrix-type liquid crystal display, when a frame frequency is reduced by setting the non-scanning period to be sufficiently larger than a scanning period while a standby image is being displayed so as to realize low power consumption, the display quality is improved.

Abstract: An active matrix display panel has (1) a plurality of row electrode lines; (2) a plurality of column electrode lines; (3) a first MOS transistor for each pixel; and (4) a second MOS transistor for each pixel. The first MOS transistor has (a) a first terminal connected to each of the column electrode line, (b) a second terminal connected to a liquid crystal, (c) a control terminal connected to each of the row electrode line, wherein an ON potential is higher than a signal potential supplied to the row electrode line. The second MOS transistor has (a) a first terminal connected to each of the row electrode line, (b) a second terminal connected to the electro-optic element, and (c) a control terminal connected to the column electrode line, wherein an ON potential is higher than a signal potential supplied to the column electrode line.

Abstract: A latch section includes a latch circuit. The latch circuit includes inverters and latches an input signal from a gating section. Between one of the inverters of the latch circuit and the output terminal OUT is disposed an analog switch whose ON/OFF characteristics are switched according to High/Low of a reset signal. Between the output terminal and an input for receiving a low potential as a power supply of a flip-flop is disposed a switching element whose ON/OFF characteristics are switched according to High/Low of the reset signal.

Abstract: A driver circuit of a display apparatus is provided with a nor circuit in each output line of a timing pulse. To the nor circuit, inputted are a timing pulse to be supplied to the output line and a pre-charge pulse for pre-charging a data signal line SL to which a write signal is being inputted based on the timing pulse.

Abstract: In a shift register of the present invention, each of flip-flops has a phase difference detection section and a waveform timing forming section as a malfunction prevention circuit. The phase difference detection section detects an overlapping waveform caused by a phase difference between clock signals SCK and SCKB, and generates an output signal A (A1, A2, . . . ) from which the overlapping portions are removed. The waveform timing forming section outputs an output signal X (X1, X2, . . . ) obtained by extracting a period when the output signal A (A1, A2, . . . ) generated in a corresponding phase difference detection section is High, when an output signal Q (Q1, Q2, . . . ) from a corresponding flip-flop is High. The output signal X (X1, X2, . . . ) sets a flip-flop in a following stage.

Abstract: A driver circuit for a display device includes NOR circuits on the input side of switches for controlling precharge of data signal lines and selected pixels connected to the data signal lines. While a video signal is written onto a data signal line, a signal instructing precharge of another data signal line is inputted from a shift register to the NOR circuits. A simultaneous precharge instruction signal is inputted from outside to the NOR circuits. According to this arrangement, precharge is performed in both a period in which a video signal is supplied to a data signal line and a period in which no video signal is supplied to any of the data signal lines. As a result, it is possible to perform precharge even with a precharge power source having relatively low driving capability, and to precharge the signal supply lines of the display device sufficiently.

Abstract: A shift register circuit includes a plurality of latch circuits connected in series to sequentially transfer a pulse signal ST from one to another, a clock signal line transmitting a clock signal CLK, and a plurality of switching circuits performing electrical connection and disconnection between the clock signal line and the plurality of latch circuits. Upon turning on the shift register, at least one of the switching circuits electrically disconnects at least one of the latch circuits from the clock signal line. During an initialization period immediately after power has been turned on, the frequency of the clock signal CLK is lower than in a normal operation period and gradually increases toward the frequency used in the normal operation period.

Abstract: A shift register circuit includes a plurality of latch circuits connected in series to sequentially transfer a pulse signal ST from one to another, a clock signal line transmitting a clock signal CLK, and a plurality of switching circuits performing electrical connection and disconnection between the clock signal line and the plurality of latch circuits. Upon turning on the shift register, at least one of the switching circuits electrically disconnects at least one of the latch circuits from the clock signal line. During an initialization period immediately after power has been turned on, the frequency of the clock signal CLK is lower than in a normal operation period and gradually increases toward the frequency used in the normal operation period.

Abstract: An output pulse of a flip flop is delayed in a delay inverter circuit before supplied to an input terminal of a level shifter. Then, an output pulse of the next stage flip flop is supplied to a reset terminal of the first flip flop and also to an enable terminal of the level shifter. Further, the level shifter output a sampling pulse with a beginning end equal to the beginning end of the pulse supplied to the input terminal and a terminal and equal to the beginning and of the pulse supplied to the enable terminal. With this arrangement, the subject invention provides a pulse output circuit, a driving circuit for a display device using the pulse output circuit, a display device and a pulse output method, that reduce delay of the terminal end of the pulse in sequentially outputting pulses from plural output terminals.