Abstract: The present invention relates to a switch control device, a power supply device, and a switch control method. A switch control device controls a switching operation of a power switch by using a feedback voltage of an output voltage. In detail, the switch control device generates the feedback current according to the feedback voltage and the feedback signal corresponding to the feedback voltage by using the feedback current. The switch control device compares the sensing signal corresponding to the drain current flowing to the power switch and the feedback signal, and turns off the power switch according to the comparison result. The switch control device increases the feedback gain rather than the feedback current during the gain compensation period after a predetermined gain compensation period, and the gain compensation period is longer than a soft start period in which the output voltage is gradually increased.

Abstract: Disclosed herein is an image forming apparatus and method thereof. The image forming apparatus includes a rotating member provided close to a distal end of a guide surface used to guide a printing medium to be introduced into a fusing unit. The rotating member comes into rolling contact with the printing medium to prevent jamming of the printing medium due to matter adhered to the distal end of the guide surface.

Abstract: The present invention relates to a power factor correction circuit and a driving method thereof. The power factor correction circuit includes: an inductor for receiving an input voltage and supplying output power; a power switch connected to the inductor to control an inductor current flowing through the inductor; an auxiliary conductor coupled to the inductor with a predetermined turn ratio; and a power factor correction controller that controls the output power by controlling the switching operation of the power switch and determines whether or not the output voltage of the output power is an over-voltage.

Abstract: The present invention relates to a power factor correction circuit and a driving method thereof. The power factor correction circuit includes a power switch controlling an inductor current flowing in an inductor, an auxiliary inductor coupled to the inductor with a predetermined turn ratio, and a power factor correction controller controlling output power by controlling a switching operation of the power switch. The power factor correction controller determines whether or not an output voltage of the output power is an over-voltage by using the sum of a source current and a sink current that control a zero current detection voltage to be included within a predetermined clamping range, the zero current detection voltage corresponding to an auxiliary voltage that is a both-end voltage of an auxiliary inductor.

Abstract: A fusing unit includes a driving source, a fusing part which includes a heat source and is driven by the driving source to heat and press a transported printing medium to fuse an image transferred to the printing medium, an electric power supplying unit which supplies an electric power to the heat source, and a control unit which senses the torque of the driving source or a property value corresponding to the torque, and restricts or blocks electric power supplied to the heat source from the electric power supplying unit during a predetermined time if a change rate of the torque or the property value deviates from a reference value.

Abstract: The present invention relates to a switch control device and a switch control method. The present invention controls a switching operation of a power switch that controls output power of a switching mode power supply (SMPS). The present invention generates an operation current corresponding to an input voltage of the SMPS and counts a compensation period in which a power supply voltage generated by the operation current increases from a predetermined counter low-reference voltage to a predetermined counter high-reference voltage. The present invention generates a compensation feedback current depending on the count result, generates a total feedback current by summing a main feedback current having a predetermined value and the compensation feedback current, and generates a power limit current of which a maximum value increases and decreases depending on the total feedback current. Turn-off of the power switch is determined by comparing the current flowing on the power switch with the power limit current.

Abstract: In a power converter, a primary coil of a transformer receives an input voltage, and a first terminal of a switch is coupled to the primary coil. An output unit includes a secondary coil of the transformer, and outputs an output voltage to which the input voltage is converted by the transformer. A switching controller receives a feedback voltage corresponding to the output voltage and a sensing voltage corresponding to a current flowing between the first terminal and a second terminal of the switch. The switching controller determines whether to perform an operation of a burst mode based on the feedback voltage. The switching controller generates a control signal by comparing the sensing voltage with a comparison voltage during a first period of the burst mode, generates the control signal by comparing the sensing voltage with a voltage corresponding to the feedback voltage during a second period of the burst mode, and transmits the control signal to a control terminal of the switch.

Abstract: A power converter according to the present invention includes a power supply unit, an output unit, and a switching controller. The power supply unit includes a primary coil of a transformer that receives an input voltage, a gate electrode, and a switch having a first electrode and a second electrode that is connected to the primary coil. The output unit includes a secondary coil of the transformer, and outputs an output voltage that is converted from the input voltage by the transformer. The switching controller includes a feedback terminal that receives a feedback voltage corresponding to the output voltage, generates a burst voltage by compensating the feedback voltage according to a maximum current value that can flow between the second electrode and the first electrode of the switch, determines whether to perform a burst mode operation according to the burst voltage, and transmits a gate signal according to performance of the burst mode operation to the gate electrode of the switch.

Abstract: The present invention relates to a switch controller and a converter having the same. The converter according to the present invention includes a power transfer device that transmits input power to an output terminal as output power, a power switch connected to a first end of the power transfer device and that controls power transmission of the power transfer device, and a switch controller that controls switching operation of the power switch. The switch controller receives an output voltage detection signal corresponding to an output voltage according to the power transmitted from the power transfer device, generates a duty control signal corresponding to a difference between the output voltage detection signal and a reference signal for controlling the output voltage, and determines turn-on/off of the power switch by using the duty control signal, and a DC gain of a feedback transfer function between the reference signal and the output voltage has a constant value.

Abstract: In a power converter, a primary coil receives an input voltage, and a switch includes a first electrode, a second electrode coupled to the primary coil, and a control electrode. An output unit includes a secondary coil, and outputs an output voltage. The primary coil and the secondary coil form a transformer, and the input voltage is converted to the output voltage by the transformer.

Abstract: A device, system, and method for providing health management services are provided. The device, system, and method analyze health data based on user health data obtained through a health measurement device and provide feedback data based on the analyzed result, thereby allowing accurate monitoring and management of the user's health status.

Abstract: An apparatus to relay connection requests between wireless devices in a wireless network including at least one piconet having a master device and one or more slave devices, the apparatus including a connection request relay unit in the master device to relay to a first wireless device a request from a second wireless device to connect to the first wireless device, wherein the first wireless device is one of the oner or more slave devices, and the second wireless device is outside the at least one piconet having the master device, and a method of relaying the connection requests.