Abstract: Short circuit failures and open circuit failures of light-emitting elements used for the backlight in an LCD panel can be reliably and easily detected. The voltage at the node between each series-connected light-emitting element array and a drive circuit is detected as a monitored voltage. A maximum detector detects the highest and a minimum detector detects the lowest of these monitored voltages. Short circuit or open circuit failure of a light-emitting element is detected by comparing the voltage difference between the maximum detector output and the minimum detector output with a specific reference voltage.

Abstract: Short circuit failures and open circuit failures of light-emitting elements used for the backlight in an LCD panel can be reliably and easily detected. The voltage at the node between each series-connected light-emitting element array and a drive circuit is detected as a monitored voltage. A maximum detector detects the highest and a minimum detector detects the lowest of these monitored voltages. Short circuit or open circuit failure of a light-emitting element is detected by comparing the voltage difference between the maximum detector output and the minimum detector output with a specific reference voltage.

Abstract: Short circuit failures and open circuit failures of light-emitting elements used for the backlight in an LCD panel can be reliably and easily detected. The voltage at the node between each series-connected light-emitting element array and a drive circuit is detected as a monitored voltage. A maximum detector detects the highest and a minimum detector detects the lowest of these monitored voltages. Short circuit or open circuit failure of a light-emitting element is detected by comparing the voltage difference between the maximum detector output and the minimum detector output with a specific reference voltage.

Abstract: The load driving apparatus according to the present invention includes a load current setting signal generating section, a load current generating section, a reference voltage generating section and a drive voltage generating section. The load current setting signal generating section generates a desired load current setting signal. The load current generating section generates a load current based on the load current setting signal to drive the load. The reference voltage generating section generates a reference voltage based on the load current setting signal. The drive voltage generating section generates a drive voltage, supplies the drive voltage to the load, generates a between-both-terminals voltage between both terminals of the load current generating section based on the drive voltage and controls the drive voltage so that the difference between the between-both-terminals voltage and the reference voltage becomes small.

Abstract: Short circuit failures and open circuit failures of light-emitting elements used for the backlight in an LCD panel can be reliably and easily detected. The voltage at the node between each series-connected light-emitting element array and a drive circuit is detected as a monitored voltage. A maximum detector detects the highest and a minimum detector detects the lowest of these monitored voltages. Short circuit or open circuit failure of a light-emitting element is detected by comparing the voltage difference between the maximum detector output and the minimum detector output with a specific reference voltage.

Abstract: A backlight drive apparatus for current driving a plurality of strings has a period in which at least one of the strings is a current driven idly during a liquid crystal OFF period, in addition to a current driving period in which video information is displayed via liquid crystals. A failure detection section can monitor stabilized detection voltages in the period when current driven idly and detects failure state of the backlight panel.

Abstract: The load driving apparatus according to the present invention includes a load current setting signal generating section, a load current generating section, a reference voltage generating section and a drive voltage generating section. The load current setting signal generating section generates a desired load current setting signal. The load current generating section generates a load current based on the load current setting signal to drive the load. The reference voltage generating section generates a reference voltage based on the load current setting signal. The drive voltage generating section generates a drive voltage, supplies the drive voltage to the load, generates a between-both-terminals voltage between both terminals of the load current generating section based on the drive voltage and controls the drive voltage so that the difference between the between-both-terminals voltage and the reference voltage becomes small.

Abstract: The N light emitting element groups each include one or more light emitting elements. The power source circuit includes a control input terminal and supplies the power source voltage to the N light emitting element groups. The N current driving circuits, each including a feedback output terminal, generate N drive currents for driving the respective N light emitting element groups and generate main feedback voltages at the feedback output terminals based on the power source voltage. The main feedback circuit applies a main feedback signal to the control input terminal based on the N main feedback voltages. The auxiliary feedback circuit applies an auxiliary feedback signal to the control input terminal based on the power source voltage. The power source circuit adjusts the power source voltage based on at least one of the main feedback signal and the auxiliary feedback signal.

Abstract: There is provided a light emitting device having a small area for mounting. The light emitting device of the invention includes a light emitting element having an electric signal terminal, that is driven to emit light by an electric signal given to the electric signal terminal from outside, and a semiconductor chip for driving the light emitting element, having a light emitting element drive circuit that is made of a semiconductor, outputs and applies the electric signal to the electric signal terminal. The light emitting elements are mounted on the surface of the semiconductor chip for driving the light emitting element, and a conductive path is provided for mutually connecting a plurality of light emitting elements on the surface of the semiconductor chip for driving the light emitting element.

Abstract: A light emitting device is provided to correctly detect a temperature of a light emitting element, and to prevent breakdown or deterioration of the light emitting element. The light emitting device of the invention includes a light emitting element having an electric signal terminal, that is driven by an electric signal given from the outside to the electric signal terminal, and a semiconductor chip for driving the light emitting element, including a light emitting element driving circuit and a temperature detecting element that are made of a semiconductor. The semiconductor chip outputs and applies the electric signal to the electric signal terminal. The temperature detecting element detects an ambient temperature. The light emitting element is mounted on the semiconductor chip for driving the light emitting element, and is driven based on the temperature detected by the temperature detecting element.

Abstract: A compact-size driving voltage controller is provided which can be driven with low power. The compact-size driving voltage controller which can be driven with low power includes a High output operational amplifier and a Low output operational amplifier for supplying driving voltages VcomH, VcomL to a load such as a liquid crystal display panel, an output switch for alternating between the outputs of the operational amplifiers, a Low voltage setting operational amplifier for generating a set voltage to be supplied to the non-inverted input terminal of the Low output operational amplifier, a set voltage generator including a current mirror circuit and a clamping circuit, a bias current controller for controlling the bias current flowing in each operational amplifier with a predetermined timing, and a timing controller for controlling the changeover timing of the output switch.

Abstract: An inductor 6 accumulates an energy therein or releases the accumulated energy according to the state of a main switch element 10 being turned ON/OFF. When the inductor 6 releases an energy, if a sub-switch element 12 is in the ON state, a current is passed through a circuit downstream of the sub-switch element 12, thereby increasing an output voltage VO1. The sub-switch element 12 is a P-channel MOS transistor, and a sub-switch control circuit 18 outputs a control signal VCT1 for the sub-switch element 12. A level shift circuit 19 receives an output-side potential VP of the inductor 6, and outputs, as a control signal VG1 applied to the gate of the sub-switch element 12, the potential VP if the control signal VCT1 is at the L level or a potential (VP?VM) lower than the potential VP if the control signal VCT1 is at the H level. Thus, the output voltage of the DC-DC converter can be made precisely equal to the target voltage.

Abstract: An inductor 6 accumulates an energy therein or releases the accumulated energy according to the state of a main switch element 10 being turned ON/OFF. When the inductor 6 releases an energy, if a sub-switch element 12 is in the ON state, a current is passed through a circuit downstream of the sub-switch element 12, thereby increasing an output voltage VO1. The sub-switch element 12 is a P-channel MOS transistor, and a sub-switch control circuit 18 outputs a control signal VCT1 for the sub-switch element 12. A level shift circuit 19 receives an output-side potential VP of the inductor 6, and outputs, as a control signal VG1 applied to the gate of the sub-switch element 12, the potential VP if the control signal VCT1 is at the L level or a potential (VP-VM) lower than the potential VP if the control signal VCT1 is at the H level. Thus, the output voltage of the DC-DC converter can be made precisely equal to the target voltage.

Abstract: A multi output DC-DC converter is provided with a main switch which is turned ON and OFF at a predetermined cycle, and applies the input DC voltage of the DC power source to the inductor when turned ON; a plurality of diodes which rectify a voltage generated in the inductor when the main switch is off; an auxiliary switch connected in series to each of the plurality of diodes; and a plurality of capacitors connected to the respective series circuits of the plurality of diodes and the auxiliary switch, which respectively output a plurality of output voltages. And a control circuit performs a time-division control of turning the main switch ON and OFF in the predetermined cycle, and of selecting one of the plurality of auxiliary switches in the predetermined cycle, to thereby output an output voltage through the selected auxiliary switch, and, in the case where an enable signal is instructing to stop, forcefully turns OFF the auxiliary switch corresponding to the enable signal.

Abstract: The present invention provides a compact-size driving voltage controller which can be driven with low power. The compact-size driving voltage controller which can be driven with low power includes a High output operational amplifier and a Low output operational amplifier for supplying driving voltages VcomH, VcomL to a load such as a liquid crystal display panel, an output switch for alternating between the outputs of the operational amplifiers, a Low voltage setting operational amplifier for generating a set voltage to be supplied to the non-inverted input terminal of the Low output operational amplifier, a set voltage generator including a current mirror circuit and a clamping circuit, a bias current controller for controlling the bias current flowing in each operational amplifier with a predetermined timing, and a timing controller for controlling the changeover timing of the output switch.

Abstract: A process for producing highly pure terephthalic acid, which comprises heating and dissolving crude terephthalic acid in water, and purifying it by contacting the aqueous solution with hydrogen at a temperature of from 260.degree. to 320.degree. C. in the presence of a platinum group metal catalyst, wherein the purification is initiated within three minutes after the aqueous solution under heating reaches a temperature of 250.degree. C.

Abstract: An aqueous slurry of calcium silicate hydrate which is formed by heating a siliceous source and a calcareous source in water to react them and which has the specific property is shaped with a press filter molding and cured by a steam curing under steam pressure to cause a transformation of the calcium silicate hydrate whereby a calcium silicate shaped product having low bulk density and high mechanical strength is obtained. The calcium silicate shaped product is suitable as a lagging product or a heat insulator.

Abstract: An aqueous slurry of calcium silicate hydrate which is formed by heating a siliceous source and a calcareous source in water to react them and which has the specific property is shaped with a press filter molding and cured by a steam curing under steam pressure to cause a transformation of the calcium silicate hydrate whereby a calcium silicate shaped product having low bulk density and high mechanical strength is obtained. The calcium silicate shaped product is suitable as a lagging product or a heat insulator.