Patent
Method and unit for driving piezoelectric transformer used for controlling luminance of cold-cathode tube
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TLDR
In this paper, a method and unit for driving a small high-efficiency piezoelectric transformer allowing a cold-cathode tube to have stable luminance by detecting only an active current flowing in the cold cathodes tube based on a phase difference between an output current and voltage of the piezolectric transform was proposed.Abstract:
A method and unit for driving a small high-efficiency piezoelectric transformer allowing a cold-cathode tube to have stable luminance by detecting only an active current flowing in the cold-cathode tube based on a phase difference between an output current and voltage of the piezoelectric transformer, removing a reactive current caused by stray capacitance formed between the cold-cathode tube and a reflector, and accurately controlling driving of the piezoelectric transformer so that a constant active current is detected.read more
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References
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Patent
Piezoelectric transformer-inverter
TL;DR: In this paper, a PWM inverter output variable circuit adjusts an average voltage supplied from a PWC inverter to a piezoelectric transformer drive circuit, and when the tube current is high, the average voltage rises.
Patent
Discharge tube driving device and piezoelectric transformer therefor
TL;DR: In this article, a driving device for driving a discharge tube was proposed, where a pair of electrodes is formed on a piezoelectric transformer, and a voltage which is periodically inverted, is applied to the electrodes.
Patent
Inverter and method for driving a plurality of cold cathode tubes in parallel
TL;DR: In this paper, a drive circuit for a piezoelectric transformer includes a master block 24 having a drive frequency control circuit for controlling the frequency of a drive voltage, at least one slave block 25 receiving an output of the above mentioned drive frequency controller circuit, and a circuit for suppressing a harmonic component of a light adjusting frequency included in the drive voltages.
Patent
Driving method and driving circuit of piezoelectric transformers
Nobuaki Honbo,Shingo Kawashima +1 more
TL;DR: In this article, the first and second piezoelectric transformers were used for outputting a voltage at a secondary terminal which is input from a primary terminal utilizing a piezelectric effect, and a driving circuit for applying a frequency voltage to each of the transformers based on frequency signals of which phases are different from each other by 180 degrees.
Patent
Method for drive piezoelectric transformer and cold-cathode tube drive circuit using it
Sasaki Hiroshi,Iguchi Koichi +1 more
TL;DR: In this article, a cold-cathode tube is operated using a piezoelectric transformer to prevent uneven brightness, where the drive frequency of the transformer is controlled so that a tube current higher than a value at which uneven brightness occurs is ensured and the tube current is constant.