摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.