In a display apparatus and a driving method thereof, a detector determines whether a timing controller is operated in a three-dimensional (3D) mode or a two-dimensional (2D) mode to output a first or second mode signal according to a result of the determination. A compensator compensates for a gamma value of a 3D image to be increased in response to a first mode signal when the 2D mode is converted to the 3D mode and decreases an increased gamma value to a gamma value for a 2D image in response to a second mode signal when the 3D mode is converted to the 2D mode.

Display apparatus and method of driving the same

A drive circuit of an image display apparatus has a correction circuit for outputting driving data that is corrected on the basis of a correction value. The correction value is a correction value that corrects variation of brightness of a plurality of pixels. The correction on the basis of the correction value is a correction such that the number of pixels to be darkened by the correction when the driving data inputted for the plurality of pixels have a common first value is fewer than the number of pixels to be darkened by the correction when the driving data inputted for the plurality of pixels have a common second value larger than the first value.

Image Display Apparatus

The present invention is directed to perform fine low-voltage control without largely increasing the circuit layout area in a low-power consumption structure. In the case of shifting a region to a low-speed mode, a system controller outputs a request signal and an enable signal to a power switch controller and a low-power drive circuit, respectively, to turn off a power switch and to perform a control so that the voltage level of a virtual reference potential becomes about 0.2 V to about 0.3V. The region operates on voltages between a power supply voltage and a virtual reference potential, so that it is controlled in the low-speed mode.

Semiconductor Integrated Circuit Device

This written description uses examples to disclose the invention, including the best mode, and also to enable one of ordinary skill in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Virtual welding system

A differential amplifying circuit that includes a differential pair and a cascode current mirror circuit that forms the load circuit of this differential pair. The cascode current mirror circuit includes a control-terminal-coupled first transistor pair, and second and third transistor pairs that receive first and second bias signals at coupled control terminals, respectively. The second transistor pair is straight-connected between the first transistor pair and the input end and the output end of the cascode current mirror circuit, and the third transistor pair is cross-connected between the first transistor pair and the input end and the output end of the cascode current mirror circuit. The second and third transistor pairs are controlled so as to each be placed in active and inactive states by changing over voltage values of the first and second bias signals, with control being exercised in such a manner that when one of these transistor pairs is in an active state, the other is in an inactive state.

Differential amplifier, data driver and display device

There is provided a gray scale display reference voltage generating circuit that can change a gamma correction characteristic in accordance with a liquid crystal material and LCD panel characteristics. Resistor elements R 0 through R 7 have a resistance ratio for gamma correction and generate gamma-corrected intermediate voltages on the basis of voltages across both input terminals V 0 and V 64. A gamma correction adjustment circuit 42 adjusts the gamma-corrected intermediate voltages upward or downward on the basis of adjustment data latched in a data latch circuit 43. By thus supplying the adjustment data corresponding to the liquid crystal material and the LCD panel characteristics to the data latch circuit 43, the gamma correction characteristic can be changed in accordance with the liquid crystal material and the LCD panel characteristics without modifying the design of a source driver.

Gray scale display reference voltage generating circuit capable of changing gamma correction characteristic and LCD drive unit employing the same

An incidental offset voltage caused by discrepancies in material and workmanship can be averaged by (1) using two input transistors of a differential amplifier alternately, and (2) switching output signals from both the input transistors through two switches provided to an output end. Consequently, a downsized, less-power-consuming, highly-reliable differential amplifier which is insensitive to an incidental offset voltage caused by discrepancies in material and workmanship can be provided. Also, by employing such a differential amplifier, a less-power-consuming and highly reliable operational amplifier and a liquid crystal driving circuit capable of showing display of an upgraded quality can be realized.

Differential amplifier, operational amplifier employing the same, and liquid crystal driving circuit incorporating the operational amplifier

An operational amplifier circuit 21 comprises transistors N14, N15 in a first output amplifier circuit 24, and transistors P24, P25 in a second output amplifier circuit 25. When a second differential amplifier circuit 23 is cut off, the output is driven by transistor P13 and transistors N14, N15. When a first differential amplifier circuit 22 is cut off, the output is driven by transistor N23 and transistors P24, P25. Therefore, if such a voltage as to cut off one differential amplifier circuit is given from opposite phase and in-phase input terminals 31, 32, the output can be produced. In such constitution, without using depletion type transistors that require particular manufacturing process, the range of the voltage that can be entered in the input terminal can be extended.

Operational amplifier circuit with an extended input voltage range

PROBLEM TO BE SOLVED: To actualize the high-reliability differential amplifier circuit of which power consumption is reduced by suppressing the circuit scale small and which is not affected by an accidental offset voltage due to variance in manufacture etc. SOLUTION: Input transistors 101 and 102 of the differential amplifier circuit are used while being replaced and an output signal is switched through switches 108 and 109 to average the accidental offset due to variance in manufacture etc. The operational amplifier circuit which has smaller power consumption and high reliability and the liquid crystal driving circuit which can make a display of higher quality can be actualized by using a differential amplifier circuit like this. COPYRIGHT: (C)1999,JPO

Differential amplifier circuit, operational amplifier circuit using same, and liquid crystal driving circuit using the operational amplifier circuit

PROBLEM TO BE SOLVED: To suppress increase in the manufacturing cost of a D/A converter and a liquid crystal driver using it and to miniaturize the size of them by suppressing a large increase in number of components even when a required number of kinds of voltage is increased due to increase in number of displayed colors and multi-gradation of display SOLUTION: A reference voltage generating circuit 801 generates 2(N-1)+1 ways of different reference voltages A selection circuit 802 stores sets of reference voltage in cross reference with all digital signals Average values of reference voltages of these sets differ from each other between the sets Upon the receipt of a digital signal, the selection circuit 802 selects a set corresponding to the received digital signal out of these sets and outputs each of the reference voltages A voltage follower circuit 803 receives the reference voltages from the selection circuit 802 and outputs the means value of the received reference voltages as its output voltage COPYRIGHT: (C)2000,JPO

Tomoaki Nakao

Papers

Gray scale display reference voltage generating circuit capable of changing gamma correction characteristic and LCD drive unit employing the same

Differential amplifier, operational amplifier employing the same, and liquid crystal driving circuit incorporating the operational amplifier

Operational amplifier circuit with an extended input voltage range

Differential amplifier circuit, operational amplifier circuit using same, and liquid crystal driving circuit using the operational amplifier circuit

D/a converter and liquid crystal driver using the same