Abstract: There are provided a thin transformer capable of being used in a thin display device such as a liquid crystal display (LCD) device, a light emitting diode (LED) display device, and a flat panel display device including the same. The transformer includes: a bobbin part including inner and outer bobbins each including a pipe shaped body part having a though-hole formed in an inner portion thereof and a flange part protruding outwardly from both ends of the body part; coils respectively wound around the inner and outer bobbins; and a core electromagnetically coupled to the coils to thereby form a magnetic path, wherein the inner bobbin is inserted into the through-hole of the outer bobbin to thereby be coupled to the outer bobbin and at least one of the inner and outer bobbins includes the flange part having a width larger than a thickness of the body part.

Abstract: There is provided a thin transformer capable of being used in a thin display device such as a liquid crystal display (LCD) device and a light emitting diode (LED) display device. The transformer includes: a bobbin part including a plurality of bobbins, each including a pipe shaped body part having a though-hole formed in an inner portion thereof, a flange part vertically protruding outwardly from both ends of the body part, and external connection terminals protruding from one side of a lower flange part formed at a lower end of the body part; a core inserted into the through-hole of the bobbin to thereby form a magnetic path; and a coil part including coils each wound around the plurality of bobbins, wherein the bobbin part includes an inner bobbin and an outer bobbin, and the inner bobbin is coupled to the outer bobbin such that the external connection terminals of the inner bobbin and the external connection terminals of the outer bobbin are opposed to each other.

Abstract: A thin transformer to be used in a thin display device such as a liquid crystal display (LCD) device and a light emitting diode (LED) display device. The transformer includes a plurality of bobbins, each including a pipe shaped body having a though-hole formed in an inner portion thereof, a flange vertically protruding outwardly from both ends of the body, and external connection terminals protruding from one side of a lower flange formed at a lower end of the body; a core inserted into through-holes of the bobbins to form a magnetic path; and coils each wound around the plurality of bobbins. The bobbins include inner and outer bobbins. The inner bobbin is coupled to the outer bobbin such that the external connection terminals of the inner bobbin and the external connection terminals of the outer bobbin are mutually opposed.

Abstract: There are provided a thin transformer capable of being used in a thin display device such as a liquid crystal display (LCD) device, a light emitting diode (LED) display device, and a flat panel display device including the same. The transformer includes: a bobbin part including inner and outer bobbins each including a pipe shaped body part having a though-hole formed in an inner portion thereof and a flange part protruding outwardly from both ends of the body part; coils respectively wound around the inner and outer bobbins; and a core electromagnetically coupled to the coils to thereby form a magnetic path, wherein the inner bobbin is inserted into the through-hole of the outer bobbin to thereby be coupled to the outer bobbin and at least one of the inner and outer bobbins includes the flange part having a width larger than a thickness of the body part.

Abstract: There is provided a thin transformer capable of being used in a thin display device such as a liquid crystal display (LCD) device and a light emitting diode (LED) display device. The transformer includes: a bobbin part including a plurality of bobbins, each including a pipe shaped body part having a though-hole formed in an inner portion thereof, a flange part vertically protruding outwardly from both ends of the body part, and external connection terminals protruding from one side of a lower flange part formed at a lower end of the body part; a core inserted into the through-hole of the bobbin to thereby form a magnetic path; and a coil part including coils each wound around the plurality of bobbins, wherein the bobbin part includes an inner bobbin and an outer bobbin, and the inner bobbin is coupled to the outer bobbin such that the external connection terminals of the inner bobbin and the external connection terminals of the outer bobbin are opposed to each other.

Abstract: There are provided a transformer and a flat panel display device having the same. The transformer includes: a bobbin, around which a coil is wound; and an input/output terminal installed in the bobbin, a lead portion of the coil wound around the bobbin being connected to the input/output terminal, wherein the input/output terminal has a stopper portion protruded from at least one face and limiting a winding position of the coil such that the lead portion of the coil is wound therearound to be separated from the bobbin.

Abstract: There are provided a thin transformer capable of being used in a thin display device such as a liquid crystal display (LCD) device, a light emitting diode (LED) display device, and a flat panel display device including the same. The transformer includes: a bobbin part including inner and outer bobbins each including a pipe shaped body part having a though-hole formed in an inner portion thereof and a flange part protruding outwardly from both ends of the body part; coils respectively wound around the inner and outer bobbins; and a core electromagnetically coupled to the coils to thereby form a magnetic path, wherein the inner bobbin is inserted into the through-hole of the outer bobbin to thereby be coupled to the outer bobbin and at least one of the inner and outer bobbins includes the flange part having a width larger than a thickness of the body part.

Abstract: There is provided a thin transformer capable of being used in a thin display device such as a liquid crystal display (LCD) device and a light emitting diode (LED) display device. The transformer includes: a bobbin part including a plurality of bobbins, each including a pipe shaped body part having a though-hole formed in an inner portion thereof, a flange part vertically protruding outwardly from both ends of the body part, and external connection terminals protruding from one side of a lower flange part formed at a lower end of the body part; a core inserted into the through-hole of the bobbin to thereby form a magnetic path; and a coil part including coils each wound around the plurality of bobbins, wherein the bobbin part includes an inner bobbin and an outer bobbin, and the inner bobbin is coupled to the outer bobbin such that the external connection terminals of the inner bobbin and the external connection terminals of the outer bobbin are opposed to each other.

Abstract: In a piezoelectric transformer for a fluorescent lamp, the size of an electrode at a central region of each side on a first face is smaller than that of electrodes at the corner region thereof. As a result, the stress generated in the piezoelectric block is minimized and the heat caused by stress is prevented, so that the damage of the piezoelectric block and the deterioration of the efficiency may be prevented. The input electrode can be formed in various shapes such as diamond, cross, and rhombic shapes.

Abstract: Disclosed is a high-power ballast inexpensively applicable to a fluorescent lamp of the 28-Watt class without any increase in the number of constituent elements used or any complexity in the manufacturing process. The high-power ballast includes a rectifier circuit for rectifying a low-frequency AC voltage to convert it into a direct current DC voltage, a power factor compensation circuit for compensating a power factor for the voltage outputted from the rectifier circuit, thereby boosting the level of the output voltage, the power factor compensation circuit including an active type power factor driver, and an inverter circuit for converting the DC voltage, outputted from the power factor compensation circuit, into a desired high-frequency AC voltage. The inverter circuit includes an inverter, a resonator circuit connected to the inverter, and a high-power piezoelectric transformer having an input terminal connected to the resonator circuit and an output terminal connected to the fluorescent lamp.

Abstract: A piezoelectric ceramic composition with superior dielectric constant, mechanical quality factor Qm and electromechanical coupling factor Kp, and a high power output piezoelectric transformer made from the composition are disclosed. The piezoelectric ceramic composition is composed of Pb [(Sb1/2Nb1/2)x (Zr0.495Ti0.505)1−x] O3+yPbO+zMnO, where x is 0.01-0.05, y is 0.3-0.6 wt %, and z is 0.7 wt % or less.

Abstract: A piezoelectric ceramic composition with superior mechanical quality factor Qm and electromechanical coupling factor Kp, and a high power output piezoelectric transformer made from the composition are disclosed. The piezoelectric ceramic composition according to the present invention is composed of Pb1−aSra[(Ni1/2W1/2)b(Mn1/3Nbz/3)c(Zr1−xTix)1−b−c]O3+kPbO, where a is 0-0.06, b is 0.01-0.05, c is 0.01-0.09, x is 0.47-0.53, and k is 0.1-0.7 wt %.

Abstract: A digitally controlled electronic ballast with a piezoelectric transformer automatically controls the brightness of a lamp in a digital frequency modulation manner. The ballast power a rectifier for rectifying an input low-frequency AC voltage to obtain a DC voltage, a power factor improving circuit for maintaining the level of the DC voltage output from the rectifier constant, an inverter for performing a switching operation, a resonance circuit for transferring a high-frequency AC voltage output from the inverter to the lamp. The resonance circuit includes a coil and a high-power piezoelectric transformer. A digital controller is provided for modulating a frequency controlling a switching period of the inverter when the lamp is turned off/off. The piezoelectric transformer is made of a composition expressed by Pb1-aSra[(Ni½W½)b(Mn⅓Nb⅔)c(Zr1-xTix)1-b-c]O3+kPbO.

Abstract: A piezoelectric ceramic composition in which the mechanical quality factor Qm and the electromechanical coupling factor Kp are superior, and a high power output piezoelectric transformer made of it are disclosed. The piezoelectric ceramic composition according to the present invention is composed of Pb1−aSra [(Ni1/2W1/2)b(Mn1/3Nb2/3)c(Zr1−xTix)1−b−c]O3+kPbO, where a is 0-0.06 mol %, b is 0.01−0.05 mol %, c is 0.01-0.09 mol %, x is 0.47-0.53 mol %, and k is 0.1-0.7 wt %. The piezoelectric transformer according to the present invention includes: a piezoelectric block composed of the same composition; a first electrode consists of an inner electrode and an outer electrode, the inner electrode being formed at a center of a top of the piezoelectric block, and the outer electrode being formed around the inner electrode by being separated by an isolating region; a second electrode is formed on the bottom of the piezoelectric block.

Abstract: A piezoelectric ceramic composition in which the dielectric constant, the mechanical quality factor Qm and the electromechanical coupling factor Kp are superior, and a high power output piezoelectric transformer made of it are disclosed. The piezoelectric ceramic composition according to the present invention is composed of Pb[(Sb1/2Nb1/2)x(Zr0.495Ti0.505)1−x]O3+yPbO+zMnO, where x is 0.01-0.05 mol %, y is 0.03-0.6 wt %, and z is 0.7 wt % or less. The piezoelectric transformer according to the present invention includes: a piezoelectric block composed of the same composition; a first electrode consists of an inner electrode and an outer electrode, the inner electrode being formed at the center of the top of the piezoelectric block, and the outer electrode being formed around the inner electrode by being separated by an isolating region; and a second electrode is formed on the bottom of the piezoelectric block.

Abstract: A digital controlled electronic ballast with a piezoelectric transformer which is capable of supplying high power of the 28-Watt class to the ballast, whereby the ballast automatically controls precisely the brightness of a lamp in a digital frequency modulation manner and applies stable voltage and current to the lamp.

Abstract: A piezoelectric ceramic composition in which the mechanical quality factor Qm and the electromechanical coupling factor Kp are superior, and a high power output piezoelectric transformer made of it are disclosed.

Abstract: A piezoelectric ceramic composition in which the dielectric constant, the mechanical quality factor Qm and the electromechanical coupling factor Kp are superior, and a high power output piezoelectric transformer made of it are disclosed.

Abstract: In the piezoelectric transformer for fluorescent lamp, the size of an electrode at the central region of each sides on the first face is smaller than that of electrode at the corner region. As a result, the stress generated in the piezoelectric block is minimized and the heat caused by the stress is prevented, so that the damage of the piezoelectric block and the deterioration of the efficient may be prevented. The input electrode can be formed in the various shapes such as diamond, cross, and rhombic shapes.

Abstract: A lead-free soldering material for soldering wires of electronic parts is disclosed. The lead-free soldering material is composed of in weight %: 3-4% of Ag, 2-5% of In, 6-14% of Bi and a balance of Sn, and the soldering material shows a superior solderability.