Abstract: In one embodiment of the present invention, a liquid crystal driving semiconductor IC for driving a display panel includes an output terminal connected to the display panel, an output circuit block including a DAC circuit, and a spare output block including a DAC circuit, the DAC circuits and being connectable to the output terminal. The IC includes an op amp for comparing output signal from the DAC circuit with that of the DAC circuit, and judging circuit for judging, based on the comparison result of the op amp, whether the DAC circuit is defective, and switches and for, if the DAC circuit is defective, connecting the spare DAC circuit to the output terminal in replacement of the defective DAC circuit. This provides an IC for driving a display device, which IC has concrete measures to easily detect a defect in an output circuit, and can perform self-healing for the defect in the output circuit.

Abstract: A drive circuit (20) of the present invention includes an output circuit block (30), a spare output circuit block (40), a reference output circuit block (41), a comparing and determining circuit (50), and switching circuits (60) and (61). During self-detection, the switching circuit (60) selects one output circuit from the output circuit block (40), disconnects the selected output circuit from a data line of a display panel (80), and connects the spare output circuit block (40) to the data line of the display panel (80). The comparing and determining circuit (50) compares a test output signal from the selected output circuit with a reference output signal from the reference output circuit block (41) and, in accordance with a result of the comparison, determines whether or not the selected output circuit is defective or not. This achieves a drive circuit capable of detecting a failure in an output circuit while driving a display panel without causing a defect in display.

Abstract: In a display device driven by multi-picture element driving, in order to realize narrowing of a frame, a gate driver provided in the display device includes buffers. Storage capacitor driving signals are inputted in the buffers. In at least one embodiment, once the storage capacitor driving signals are inputted, the buffers shape waveforms of the storage capacitor driving signals, and outputs the storage capacitor driving signals thus shaped to storage capacitor wires via terminals “CSVtypeA1?R” to “CSVtypeA4?R” and terminals “CSVtypeA1?L” to “CSVtypeA4?L”. The buffers supply storage capacitor driving signals reduced in waveform rounding as such, to drive a storage capacitor that is connected to the storage capacitor wires.

Abstract: In one embodiment of the present invention, a liquid crystal driving semiconductor IC for driving a display panel includes an output terminal connected to the display panel, an output circuit block including a DAC circuit, and a spare output block including a DAC circuit, the DAC circuits and being connectable to the output terminal. The IC includes an op amp for comparing output signal from the DAC circuit with that of the DAC circuit, and judging circuit for judging, based on the comparison result of the op amp, whether the DAC circuit is defective, and switches and for, if the DAC circuit is defective, connecting the spare DAC circuit to the output terminal in replacement of the defective DAC circuit. This provides an IC for driving a display device, which IC has concrete measures to easily detect a defect in an output circuit, and can perform self-healing for the defect in the output circuit.

Abstract: The display device drive unit includes a liquid crystal driver that generates a liquid crystal driving voltage for display device driving, and can operate in a master mode for outputting the foregoing voltage and in a slave mode for driving the display device in accordance with the liquid crystal driving voltage that has been inputted from the outside. The display device drive unit further includes a selection register for storing mode information that indicates whether the liquid crystal drivers is set to be in the master mode or the slave mode, and the liquid crystal driver outputs the liquid crystal voltage when the mode information indicative of the master mode is stored, and stops outputting the foregoing voltage when the mode information indicative of the slave mode is stored.

Abstract: A line inverse driving method is performed by outputting voltages for gradation display in mutually reverse polarities with respect to pixels adjacent in a data signal line direction. A separation switch is provided between an output stage of a data driver and a data signal line to separate them. In a blanking period, the data signal line is cut off, and in the selection-scanning period of a scanning signal line to be scanned first, the scanning signal line to be scanned next is also subjected to the selection-scanning. With this structure, respective charges in adjacent pixel capacitors are neutralized, and it is therefore possible to reduce a power consumption. Further, since a short-circuit can be performed at short distance, the problem of dull waveform can be suppressed, thereby realizing an image display device suited for a large screen.

Abstract: A driving apparatus of liquid crystal display apparatus of the present invention has a changeover control circuit for controlling each switching of the inputs and outputs of first and second amplifier circuits. In the changeover control circuit, an offset voltage applied to a pixel by the first and second amplifier circuits is changed in its polarity for every predetermined number of frames in accordance with a switch changeover signal for operational amplifier and an alternation switch changeover signal input and the offset voltage is canceled by frames whose number is twice as many as the predetermined number of frames. This allows the circuit to cancel the offset voltage by the frames and to avoid that the display unevenness is discernible by human eyes, thereby ensuring to provide driving apparatus and driving method of liquid crystal display apparatus that can carry out the display with high quality.

Abstract: A liquid crystal panel includes a plurality of a data line electrode and a plurality of a scanning line electrode crossing each other and forming a pixel arranged in a matrix at the intersection of these two. A mounting package is connected to an edge of a side of a glass substrate of the liquid crystal panel. On an insulating film base of the mounting package, an LSI chip for driving the data line electrode and an LSI chip for driving the scanning line electrode are mounted. The former LSI chip is provided to be close to the liquid crystal panel compared to the latter. A set of wires connecting a group of connecting terminals to the LSI chip is fixed on the film base so as to pass under the LSI chip (mounting area) on the film base. On this account, it is possible to provide a set of wires, which is not connected to the drive LSI chip, in the shortest distance without disconnecting the same, in an arrangement in which a plurality of drive LSI chips is mounted on the liquid crystal panel etc.

Abstract: A liquid crystal driving device of the present invention is provided with a display data memory of a capacity that can be divided into two parts, and a switch circuit that is used to switch an addressing method of the display data memory between multi-tone display in a dual-scan and simple-tone display in a single-scan, so as to enable a driving IC to be shared between liquid crystal display devices that are used to display high-quality and multi-tone images and liquid crystal display devices that require less tone. Such a liquid crystal driving device can be used to reduce production cost of various types of liquid crystal display devices.

Abstract: A source driver 92 of the present invention has a reference voltage generator 38 for generating tone display voltages, and a DA converter 36 for selecting and outputting a tone display voltage to a liquid crystal panel. In the source driver 92, a buffer circuit section 41 is provided between the reference voltage generator 38 and the DA converter 36. The buffer circuit section 41 includes a buffer, and analog switch circuits which switch modes of connection between the reference voltage generator 38, the buffer, and the DA converter 36, so as to select whether to output the tone display voltage to the DA converter 36 via the buffer or without utilizing the buffer. Operations of the analog switch circuits are controlled by the analog switch circuit section 40.

Abstract: A power supply in accordance with the present invention includes: a resistance voltage-dividing circuit for generating an intermediate voltage, to which a targeted voltage value is allocated, from a supplied voltage; an N-type transistor which causes a current flow into from an outside when the intermediate voltage is higher than the targeted voltage value; a P-type transistor which outputs a current to the outside when the intermediate voltage is lower than the targeted voltage value; differential amplifier circuits having a voltage-follower arrangement, in each of the circuits the fluctuation acceptance range of the intermediate voltage with respect to the targeted voltage value being arranged so as to be equivalent to the difference between the operation-starting voltage of the N-type transistor and the operation-starting voltage of the P-type transistor; and resistances which activate either the P-type transistor or the N-type transistor so as to regulate the intermediate voltage by making the intermediat

Abstract: The display device drive unit includes a liquid crystal driver that generates a liquid crystal driving voltage for display device driving, and can operate in a master mode for outputting the foregoing voltage and in a slave mode for driving the display device in accordance with the liquid crystal driving voltage that has been inputted from the outside. The display device drive unit further includes a selection register for storing mode information that indicates whether the liquid crystal drivers is set to be in the master mode or the slave mode, and the liquid crystal driver outputs the liquid crystal voltage when the mode information indicative of the master mode is stored, and stops outputting the foregoing voltage when the mode information indicative of the slave mode is stored.

Abstract: A power supply in accordance with the present invention includes: a resistance voltage-dividing circuit for generating an intermediate voltage, to which a targeted voltage value is allocated, from a supplied voltage; an N-type transistor which causes a current flow into from an outside when the intermediate voltage is higher than the targeted voltage value; a P-type transistor which outputs a current to the outside when the intermediate voltage is lower than the targeted voltage value; differential amplifier circuits having a voltage-follower arrangement, in each of the circuits the fluctuation acceptance range of the intermediate voltage with respect to the targeted voltage value being arranged so as to be equivalent to the difference between the operation-starting voltage of the N-type transistor and the operation-starting voltage of the P-type transistor; and resistances which activate either the P-type transistor or the N-type transistor so as to regulate the intermediate voltage by making the intermediat

Abstract: A liquid crystal driving device of the present invention is provided with a display data memory of a capacity that can be divided into two parts, and a switch circuit that is used to switch an addressing method of the display data memory between multi-tone display in a dual-scan and simple-tone display in a single-scan, so as to enable a driving IC to be shared between liquid crystal display devices that are used to display high-quality and multi-tone images and liquid crystal display devices that require less tone. Such a liquid crystal driving device can be used to reduce production cost of various types of liquid crystal display devices.

Abstract: A line inverse driving method is performed by outputting voltages for gradation display in mutually reverse polarities with respect to pixels adjacent in a data signal line direction. A separation switch is provided between an output stage of a data driver and a data signal line to separate them. In a blanking period, the data signal line is cut off, and in the selection-scanning period of a scanning signal line to be scanned first, the scanning signal line to be scanned next is also subjected to the selection-scanning. With this structure, respective charges in adjacent pixel capacitors are neutralized, and it is therefore possible to reduce a power consumption. Further, since a short-circuit can be performed at short distance, the problem of dull waveform can be suppressed, thereby realizing an image display device suited for a large screen.

Abstract: A liquid crystal panel includes a plurality of a data line electrode and a plurality of a scanning line electrode crossing each other and forming a pixel arranged in a matrix at the intersection of these two. A mounting package is connected to an edge of a side of a glass substrate of the liquid crystal panel. On an insulating film base of the mounting package, an LSI chip for driving the data line electrode and an LSI chip for driving the scanning line electrode are mounted. The former LSI chip is provided to be close to the liquid crystal panel compared to the latter. A set of wires connecting a group of connecting terminals to the LSI chip is fixed on the film base so as to pass under the LSI chip (mounting area) on the film base. On this account, it is possible to provide a set of wires, which is not connected to the drive LSI chip, in the shortest distance without disconnecting the same, in an arrangement in which a plurality of drive LSI chips is mounted on the liquid crystal panel etc.

Abstract: A source driver 92 of the present invention has a reference voltage generator 38 for generating tone display voltages, and a DA converter 36 for selecting and outputting a tone display voltage to a liquid crystal panel. In the source driver 92, a buffer circuit section 41 is provided between the reference voltage generator 38 and the DA converter 36. The buffer circuit section 41 includes a buffer, and analog switch circuits which switch modes of connection between the reference voltage generator 38, the buffer, and the DA converter 36, so as to select whether to output the tone display voltage to the DA converter 36 via the buffer or without utilizing the buffer. Operations of the analog switch circuits are controlled by the analog switch circuit section 40.

Abstract: A driving apparatus of liquid crystal display apparatus of the present invention has a changeover control circuit for controlling each switching of the inputs and outputs of first and second amplifier circuits. In the changeover control circuit, an offset voltage applied to a pixel by the first and second amplifier circuits is changed in its polarity for every predetermined number of frames in accordance with a switch changeover signal for operational amplifier and an alternation switch changeover signal input and the offset voltage is canceled by frames whose number is twice as many as the predetermined number of frames. This allows to cancel the offset voltage by the frames and to avoid that the display unevenness is discernible by human eyes, thereby ensuring to provide driving apparatus and driving method of liquid crystal display apparatus that can carry out the display with high quality.

Abstract: A start signal is given to an SP.sub.-- I/O buffer through a terminal SP1, and its pulse width is controlled by an SP control circuit. A selection signal SEL is given to a selector circuit so that the data shift direction of a bidirectional shift register is switched. When the shift direction is directed to the other side, the start signal is supplied from a terminal SP2 through an SP.sub.-- I/O buffer. When the shift operation is to be done from the terminal SP1 to the terminal SP2, the output of the 38th stage which precedes the final stage, namely, the 40th stage, by two stages is derived from the terminal SP2 as an input start signal for the succeeding driver, during a time period which is longer than one cycle of a clock signal CLK. According to this configuration, a cascade connection can be realized easily and surely even when a clock signal of a higher frequency is used.

Abstract: When an IC card is attached to a terminal unit, a counter counts pulses of an external clock signal and a switching circuit outputs the external clock signal to an internal circuit in place of an internal clock signal if a NAND gate determines that the count of pulses of the external clock signal by the counter is a predetermined value. When the IC card is ejected from the terminal unit, pulses of the internal clock signal are counted by a counter and when the count attains a predetermined value, the counter is cleared and the switching circuit outputs the internal clock signal to the internal circuit in place of the external clock signal in response to the output of the NAND gate. Thus, it can be correctly determined whether the IC card is operated in the form of a single body or in the form attached to any terminal unit.