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: A wireless communication device includes an antenna, a transceiver, a filter circuit and an attenuation circuit. The transceiver includes a transmission electrode and a receive electrode, and communicates with an external device through the antenna. The filter circuit is coupled between the transmission electrode and the antenna, and includes a harmonic trap circuit that eliminates a harmonic element of a carrier frequency of an outgoing signal provided from the transceiver through the transmission electrode. The attenuation circuit is coupled between the receive electrode and the antenna, and provides an incoming signal received through the antenna to the receive electrode after reducing a voltage of the incoming signal.

Abstract: A resonant converter includes a first switch coupled between a first node and a primary side ground, a second switch coupled between an input voltage and the first node, at least one capacitor and at least one inductor coupled in series between both ends of the first switch, and a switch control circuit that shifts switching frequencies of the first and second switches during a period for which an abnormal event lasts when occurrence of the abnormal event is detected, and shifts the switching frequencies in an opposite direction when the abnormal event ends.

Abstract: A resonant converter includes a primary-side winding electrically coupled to an input voltage, a secondary-side winding electrically coupled to a load, first and second switches coupled to one end of the primary-side winding, and a switch control circuit configured to differently control switching frequency limit ratios of the first and second switches by differently limiting a frequency variation ratio of a first clock signal that determines switching frequencies of the first and second switches according to variation of one of the input voltage and the load.

Abstract: This disclosure provides control techniques for a resonant converter. In one embodiment, a resonant converter controller includes predictive gate drive circuitry configured to generate a predictive gate drive signal indicative of a time duration from a rising edge of a first drive signal for controlling a conduction state of a first inverter switch of a resonant converter system to a synchronous rectifier (SR) current zero crossing instant of a first SR switch of the resonant converter system, wherein the first tracking signal is based on at least the first drive signal and a voltage drop across the first SR switch. The resonant converter controller may also include SR gate drive shrink circuitry configured to generate an SR gate drive turn on delay signal to increase delay of SR on times in response to detection of a decrease in load current demand of the resonant converter system.

Abstract: A resonant converter includes a first switch on a primary side and a second switch coupled to the first switch, a first synchronous rectification switch on a secondary side conducted according to a switching operation of the first switch, a second synchronous rectification switch on the secondary side conducted according to a switching operation of the second switch, and a switch control circuit configured to detect a waveform of one end voltage of at least one of the first synchronous rectification switch and the second synchronous rectification switch, determine one of a below region and an above region, and differently control conduction duration of the first and second synchronous rectification switches according to a determined result.

Abstract: Reader receivers including a sample clock providing unit are provided. The sample clock providing unit may be configured to generate a plurality of first clock signals of equivalent frequency that are out-of-phase relative to each other and further configured to generate first and second sample clock signals of unequal phase from selected ones of the plurality of first clock signals by comparing a respective phase of each of the plurality of first clock signals against a phase of a reference clock signal.

Abstract: A device for preparing bio-oil, a system for preparing bio-oil and a method for preparing bio-oil using the same are provided. Biomass is supplied to an inclined portion of a reactor, and high-temperature hot sand is supplied to an upper side of the biomass supplied to the inclined portion. Then, a heater heats the inclined portion. Thus, the fast pyrolysis performance of the biomass can be enhanced, thereby increasing the yield of bio-oil. Also, combustion gas produced from the heater is supplied to the interior of the reactor, so that the interior of the reactor can be simply formed under a nonoxidizing atmosphere. Accordingly, the device for preparing bio-oil can be manufactured into a very simple structure.

Abstract: A receiver of a near field communication device includes a local oscillator, a first channel, and a second channel. The local oscillator may be configured to generate a first local oscillating signal. The first channel may be configured to process an input signal by mixing the input signal with the first local oscillating signal. The second channel may be configured to process the input signal by mixing the input signal with a second local oscillating signal that has a phase difference of 90 degrees with respect to the first local oscillating signal. Each of the first and second channels may include a comparator unit that includes a comparator configured to compare, in a comparator mode, an amplifier output signal with a reference voltage whose level increases in a step-wise manner and the comparator unit may be configured to set a level of the reference voltage to be used in a normal mode based on an output signal of the comparator.

Abstract: A voltage adjusting circuit is provided includes an inducing circuit configured to induce a voltage from electromagnetic waves, a first rectifying circuit configured to rectify an output voltage of the inducing circuit, a control circuit configured to control an output voltage of the first rectifying circuit in response to the output voltage of the first rectifying circuit, and a second rectifying circuit configured to simultaneously rectify and regulate the output voltage of the inducing circuit in response to the output voltage of the first rectifying circuit.

Abstract: Disclosed are a switch controller, a switch control method, a converter using the same, and a driving method thereof. A first voltage is generated by using a voltage that is input to an input terminal, and a soft start signal is generated by using the first voltage during a soft start duration. A switching operation is controlled by using the soft start signal during the soft start duration.

Abstract: A control circuit of a resonant power converter is disclosed. The control circuit comprises a first transistor and a second transistor for switching a transformer and a resonant tank comprising a capacitor and an inductor. A controller is configured to receive a feedback signal correlated to the output of the power converter for generating a first switching signal and a second switching signal to drive the first transistor and the second transistor, respectively. A diode coupled to the first transistor and the resonant tank for detecting the state of the first transistor and generating a detection signal for the controller. The detection signal indicates if the transistors are in a zero voltage switching (ZVS) state. If the transistors are not in the ZVS state, the switching frequency of the transistors will be increased.

Abstract: A wireless communication device includes an antenna, a transceiver, a filter circuit and an attenuation circuit. The transceiver includes a transmission electrode and a receive electrode, and communicates with an external device through the antenna. The filter circuit is coupled between the transmission electrode and the antenna, and includes a harmonic trap circuit that eliminates a harmonic element of a carrier frequency of an outgoing signal provided from the transceiver through the transmission electrode. The attenuation circuit is coupled between the receive electrode and the antenna, and provides an incoming signal received through the antenna to the receive electrode after reducing a voltage of the incoming signal.

Abstract: A control circuit of a resonant power converter is disclosed. The control circuit comprises a first transistor and a second transistor for switching a transformer and a resonant tank comprising a capacitor and an inductor. A controller is configured to receive a feedback signal correlated to the output of the power converter for generating a first switching signal and a second switching signal to drive the first transistor and the second transistor, respectively. A diode coupled to the first transistor and the resonant tank for detecting the state of the first transistor and generating a detection signal for the controller. The detection signal indicates if the transistors are in a zero voltage switching (ZVS) state. If the transistors are not in the ZVS state, the switching frequency of the transistors will be increased.

Abstract: A voltage adjusting circuit is provided includes an inducing circuit configured to induce a voltage from electromagnetic waves, a first rectifying circuit configured to rectify an output voltage of the inducing circuit, a control circuit configured to control an output voltage of the first rectifying circuit in response to the output voltage of the first rectifying circuit, and a second rectifying circuit configured to simultaneously rectify and regulate the output voltage of the inducing circuit in response to the output voltage of the first rectifying circuit.

Abstract: The present invention relates to a switch control device and a converter including the same. According to an exemplary embodiment of the present invention, the switch control device includes a PWM controller for forcing a power switch to turn on when the power switch is turned off during a predetermined period, a current sensor for determining whether a current flows through the power switch, and a conditional counter for determining that an input voltage is input to a power transmission element by using a sense result of the current sensor and a number of times that the PWM controller turns on the power switch by force.

Abstract: The present invention relates to a converter and a driving method thereof. The converter includes a switch controller that controls switching operation of a master switch and a slave switch. The switch controller detects a center point of one switching operation period of the master switch by using an internal triangular wave having a period that is the same as that of the one switching operation period, and starts the switching operation of the slave switch at the detected point. The internal triangular wave signal has a waveform that varies within one period, and detects a crossing point of an average value of the internal triangular wave and the internal triangular wave as a center point of one switching operation period of the master switch.

Abstract: Disclosed are a switch controller, a switch control method, a converter using the same, and a driving method thereof. A first voltage is generated by using a voltage that is input to an input terminal, and a soft start signal is generated by using the first voltage during a soft start duration. A switching operation is controlled by using the soft start signal during the soft start duration.

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: Disclosed are a switch controller, a switch control method, a converter using the same, and a driving method thereof. A first voltage is generated by using a voltage that is input to an input terminal, and a soft start signal is generated by using the first voltage during a soft start duration. A switching operation is controlled by using the soft start signal during the soft start duration.