Samsung Electronics Co., Ltd.

Lg Semicon Co., Ltd.

Hewlett-packard Development Company, L.P.

Korea University Research and Business Foundation

Jong-moon Choi

Jin-ha Kim

Joong-Gi Kwon

Jee-hoon Jung

Sung-jo Jo

Young Jin Song

Chang Reol Kim

Jung-Bin Kim

Ki-ho Park

Joon-gi Kwon

A multi-voltage power supply including a transformer including a primary coil, a first secondary coil, and at least one second secondary coil, a first output unit to output a first output voltage by using a voltage transferred to the first secondary coil of the transformer, at least one second output unit to output at least one second output voltage by using a voltage transferred to the at least one second secondary coil of the transformer, and a power reduction mode controller to control the at least one second output unit to turn off independent of the first output unit according to an external control signal.

Multi-voltage power supply and electronic apparatus including the same

An apparatus and method for controlling the power supplied to a fixing unit are provided. The apparatus includes a voltage detector detecting a voltage of input power supplied to heat at least one heating lamp, a synch signal generator generating a synch signal in response to the detected voltage, a switching unit switching a supply path of the input power to be applied to the at least one heating lamp, and a controller having table information of temporal duty level values of the input power that is initially supplied, and outputting a control signal for controlling a switching operation of the switching unit using the generated synch signal and the table information, wherein the switching unit performs the switching operation corresponding to the control signal. Accordingly, by sequentially increasing the input power for initial heating of the heating lamps, flickering and harmonic characteristics of a display device can be reduced, and by setting the duty level values to supply the maximum input power within a certain time, an initial heating time of the heating lamps can be minimized.

Apparatus and method for controlling power supplied to fixing unit

A switching power source apparatus includes a converting unit to convert a voltage level of power, a first switch to switch power supplied to the converting unit, a second switch connected in series with the first switch and turned on after the first switch has been turned on, and a voltage clamp unit to clamp a level of a voltage applied across the series connection of the first switch and the second switch to a predetermined voltage or less.

Switching power source apparatus and control method thereof

A switching mode power supply and a method of operating the power supply in a power save mode. The switching mode power supply includes a first PWM controller and a second PWM controller that are driven by different driving voltages and control first and the second voltages to be output, respectively, a first transformer that is controlled by the first PWM controller to output the first voltage and having a primary coil, a secondary coil to induce the first voltage, and an auxiliary winding, and a rectifier that rectifies and smoothes a current flowing through the auxiliary winding of the first transformer, generates a power save mode voltage based on the respective driving voltages of the first and the second PWM controllers, and supplies the power save mode voltage to the first and the second PWM controllers. Accordingly, the power save mode is operated using a voltage difference without requiring an extra controller.

Switching mode power supply and a method of operating the power supply in a power save mode

A switching power source apparatus includes a storage unit to store energy obtained from input power supplied to the storage unit, and to output at least of the stored energy as output power; a first switch; a second switch connected in series with the first switch, the series connection of the first switch and the second switch being connected to the storage unit; and a voltage clamp unit to clamp a level of a voltage applied across the series connection of the first switch and the second switch to a predetermined voltage or less. The first switch is turned on while the second switch is still turned off, and then the second switch is turned on after the first switch has been turned on to supply the input power to the storage unit from the series connection of the first switch and the second switch.

An image fixing apparatus that senses temperature of a heater and controls the temperature accurately includes a pair of fixing rollers, a heater housed inside at least one of the pair of fixing rollers, and a sensor integrally formed with the heater to detect temperatures of the heater from a plurality of sensing positions. The sensor includes an array of sensing units connected in parallel to the plurality of sensing positions, and generates one sensing signal. An image forming apparatus includes the image forming apparatus. An image fixing temperature control method includes generating average temperature information of a heater; and controlling the driving of the heater based on the temperature information.

Image fixing apparatus, image forming apparatus using the same, and image fixing temperature control method thereof

A high voltage power supply and a high voltage power control method thereof. The high voltage power supply includes a high voltage generation part to generate a high voltage, and a pulse width modulation (PWM) generation part to generate a pulse width modulation signal according to an output control value and to control the high voltage generation part to generate the high voltage using the generated pulse width modulation signal, when a high voltage output setting signal having the output control value is received by the PWM generation part to indicate the high voltage to be generated. Therefore, it is possible to automatically output a high voltage as desired without requiring an offline setting. In addition, although a voltage set and/or an output load are changed, the changed voltage set and/or the output load are automatically compensated so that a constant high voltage output can be output with a variety of different devices having different loads and power requirements.

High voltage power supply and a high voltage power control method thereof

A switching mode power supply and a method for outputting voltage therefrom are provided, where a transformer receives rectified alternating current (AC) voltage and transforms a voltage value or a current value, a switching transistor is connected to one end of a first coil and controls a level of power supplied to the first coil, a heat sink is positioned adjacent to the switching transistor and attenuates electromagnetic wave noise of the switching transistor; and a capacitive device is set up in an electric power line connecting the heat sink to a first side grounding end coupled with the other end of the first coil of the transformer. Accordingly the switching mode power supply can be miniaturized while effectively attenuating the electromagnetic wave noise from the switching transistor.

Switching mode power supply and method for outputting voltage therefrom

A capacitor and a method of manufacturing a capacitor which includes the steps of sequentially forming an insulating layer and an etch stop layer over a semiconductor substrate; selectively etching the etch stop layer and the insulating layer to form a contact hole; forming a plug within the contact hole; forming a pillar on the etch stop layer adjacent to the plug and on the plug; forming a dielectric layer at the sides of the pillar; removing the pillar and forming a conductive layer over the dielectric layer; and forming an insulating layer over the conductive layer and etching the insulating layer and the conductive layer to expose the upper portion of the dielectric layer.

Method of manufacturing a capacitor

A method of forming a capacitor for a semiconductor memory device, includes the steps of forming first and second insulating layers to form a first contact hole on a substrate, forming a first conductive layer and a third insulating layer within the first contact hole so as to define a second contact hole, forming a second conductive layer within the second contact hole, removing the second and third insulating layers to form a storage electrode, and forming a dielectric layer and a third conductive layer on the storage electrode to form a capacitor.

Method of forming a capacitor for a semiconductor device

A method for fabricating a transistor includes the steps of forming a gate insulation film on a substrate, forming a gate electrode on the gate insulation film and forming a first insulation film pattern on the gate electrode. A side wall spacer is formed at side surfaces of the first insulation film pattern and the gate electrode. The gate insulation film is etched to expose a portion of a surface of the substrate. An epitaxial layer is formed on the substrate where the gate insulation film is etched. The side wall spacer is removed and a thermal oxide film is grown on a portion corresponding to where the side wall spacer is removed and on an upper portion of the epitaxial layer. A source/drain region is formed by ion-implanting an impurity into the epitaxial layer.

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Seoul, South Korea

Jong-moon Choi