Abstract: A power supply device includes a power switch, a power delivering means configured to convert an input in accordance with switching operation of the power switch and output a result, and a switch control circuit configured to linearly control switching frequency of the power switch in accordance with an output detection voltage corresponding to an output voltage according to the output.

Abstract: Embodiment relates to a switch control circuit, a switch control method, and a power supply using the switch control circuit. The power supply supplies power to a load using an input voltage. The switch control circuit controls a switching operation of the power switch that controls the power supply. The switch control circuit detects a duty of the power switch using a signal for controlling the switching operation of the power switch, detects the load using the feedback voltage, and determines a short-circuit of the sense resistor according to the detected duty and the detected load.

Abstract: The present invention relates to a switching mode power supply and a driving method thereof. In the present invention, a supply voltage is generated by using a start voltage that corresponds to input power, and a switching operation frequency of a power switch is changed according to an increase/decrease of the supply voltage.

Abstract: The present invention relates to a gate driving circuit, a switch control circuit including the gate driving circuit, and a power supply. The gate driving circuit generates a gate voltage of the power switch. The gate driving circuit includes: a delay control circuit generating a first control signal that controls a rising slope of the gate voltage at a first time after a first delay period is passed from a rising time of the gate voltage and generating a second control signal that controls the rising slope of the gate voltage at a time after a second delay period is passed from the first time; and a temperature compensation circuit that varies the first delay period according to a temperature.

Abstract: A power supply device includes a power switch, a power delivering means configured to convert an input in accordance with switching operation of the power switch and output a result, and a switch control circuit configured to linearly control switching frequency of the power switch in accordance with an output detection voltage corresponding to an output voltage according to the output.

Abstract: The present invention relates to a switch controller, a switch control method, and a power supply using the switch controller. A switch controller controls switching operation of a power switch and receives a sense voltage of a sense resistor to which a drain current flowing in the power switch flows. The switch controller generates a sum signal using the sense voltage and a ramp signal having a cycle that is the same as a switching cycle of the power switch. The switch controller determines short-circuit of the sense resistor by detecting slope variation of the sum signal.

Abstract: The present invention relates to a thermal shutdown unit, a switch controller including the same, and a method controlling a thermal shutdown protection operation. The present invention determines the operation state of an SMPS to vary a reference temperature for controlling a thermal shutdown protection operation according to an operation state of the SMPS.

Abstract: The present invention relates to a gate driving circuit, a switch control circuit including the gate driving circuit, and a power supply. The gate driving circuit generates a gate voltage of the power switch. The gate driving circuit includes: a delay control circuit generating a first control signal that controls a rising slope of the gate voltage at a first time after a first delay period is passed from a rising time of the gate voltage and generating a second control signal that controls the rising slope of the gate voltage at a time after a second delay period is passed from the first time; and a temperature compensation circuit that varies the first delay period according to a temperature.

Abstract: Embodiment relates to a switch control circuit, a switch control method, and a power supply using the switch control circuit. The power supply supplies power to a load using an input voltage. The switch control circuit controls a switching operation of the power switch that controls the power supply. The switch control circuit detects a duty of the power switch using a signal for controlling the switching operation of the power switch, detects the load using the feedback voltage, and determines a short-circuit of the sense resistor according to the detected duty and the detected load.

Abstract: The present invention relates to a switch controller, a switch control method, and a power supply using the switch controller. A switch controller controls switching operation of a power switch and receives a sense voltage of a sense resistor to which a drain current flowing in the power switch flows. The switch controller generates a sum signal using the sense voltage and a ramp signal having a cycle that is the same as a switching cycle of the power switch. The switch controller determines short-circuit of the sense resistor by detecting slope variation of the sum signal.

Abstract: The present invention relates to a power supply device generating an output power by using an AC line voltage generated through rectification of an AC input, and a driving method thereof. The power supply device controls the switching operation of the power switch by using a sensing voltage corresponding to the drain current flowing to the power switch and the feedback voltage corresponding to the output voltage. The power supply device controls the feedback current every switching cycle to generate a threshold voltage, and compares the sensing voltage and the threshold voltage to control the turn-off of the power switch. The feedback current includes the first current to generate the feedback voltage, and the threshold voltage follows a curved line waveform in which the increasing slope is decreased during the switching cycle.

Abstract: The present invention relates to a power supply device generating an output power by using an AC line voltage generated through rectification of an AC input, and a driving method thereof. The power supply device controls the switching operation of the power switch by using a sensing voltage corresponding to the drain current flowing to the power switch and the feedback voltage corresponding to the output voltage. The power supply device controls the feedback current every switching cycle to generate a threshold voltage, and compares the sensing voltage and the threshold voltage to control the turn-off of the power switch. The feedback current includes the first current to generate the feedback voltage, and the threshold voltage follows a curved line waveform in which the increasing slope is decreased during the switching cycle.

Abstract: The present invention relates to a thermal shutdown unit, a switch controller including the same, and a method controlling a thermal shutdown protection operation. The present invention determines the operation state of an SMPS to vary a reference temperature for controlling a thermal shutdown protection operation according to an operation state of the SMPS.

Abstract: A switching mode power supply and a switch thereof are provided. The switch includes a plurality of first transistors, and a second transistor that is turned on/off by a control signal that is equal to that of the plurality of first transistors and in which a second current corresponding to a first current flowing to the plurality of first transistors flows, wherein a ratio of the first current to the second current sequentially changes from a time point at which the second transistor is turned on. Therefore, a switching mode power supply and a switch thereof that can always uniformly sustain a maximum limit current flowing to the switch regardless of a level of an input voltage without including a special additional circuit can be provided.

Abstract: A current controlled switching mode power supply is provided. A turn on/off time of a switching device is adjusted by controlling a leading edge blanking (LEB) time and an external drive current of the switching device by means of a switching controller, thus capable of preventing a switching current from being excessive due to a delay of a turn-off time of the switching device, which is caused by a circuit delay during a soft start of the switching mode power supply. Also, it is possible to prevent a switching current from being excessive due to a failure of accurately controlling a turn-off time of the switching device because of a delay caused when an output voltage (a voltage at a secondary winding of a transformer) of the switching mode power supply is designed to have a high voltage.

Abstract: The present invention relates to a switching mode power supply and a driving method thereof. In the present invention, a supply voltage is generated by using a start voltage that corresponds to input power, and a switching operation frequency of a power switch is changed according to an increase/decrease of the supply voltage.

Abstract: A switching mode power supply includes a power supply, a feedback circuit, and a switching controller. The power supply includes a main switch coupled to a primary coil of a transformer and supplies power to a secondary coil of the transformer according to an operation of the main switch. The feedback circuit generates a feedback voltage corresponding to an output voltage applied to the secondary coil. The switching controller compensates a propagation delay by controlling a duty of the main switch according to a result of comparing a first signal that fluctuates according to a first voltage corresponding with a current flowing through the main switch to a reference voltage corresponding to the feedback voltage.

Abstract: A switching mode power supply and a switch thereof are provided. The switch includes a plurality of first transistors, and a second transistor that is turned on/off by a control signal that is equal to that of the plurality of first transistors and in which a second current corresponding to a first current flowing to the plurality of first transistors flows, wherein a ratio of the first current to the second current sequentially changes from a time point at which the second transistor is turned on. Therefore, a switching mode power supply and a switch thereof that can always uniformly sustain a maximum limit current flowing to the switch regardless of a level of an input voltage without including a special additional circuit can be provided.

Abstract: In an EMI canceller, a control signal generation unit includes a counter, a second flip-flop, and a multiplexer. The counter outputs first and second output signals and includes first flip-flops in series. An output of the first flip-flop reverses at every cycle of the first and second output signals of a previous first flip-flop. An output of the second flip-flop reverses at every cycle of the first or second output signal of a final first flip-flop. The second flip-flop outputs third and fourth output signals. The multiplexer passes the first output signals of the first flip-flop as a control signal when the third output signal is a first level, and passes the second output signals as the control signal when it is a second level.

Abstract: A current controlled switching mode power supply is provided. A turn on/off time of a switching device is adjusted by controlling a leading edge blanking (LEB) time and an external drive current of the switching device by means of a switching controller, thus capable of preventing a switching current from being excessive due to a delay of a turn-off time of the switching device, which is caused by a circuit delay during a soft start of the switching mode power supply. Also, it is possible to prevent a switching current from being excessive due to a failure of accurately controlling a turn-off time of the switching device because of a delay caused when an output voltage (a voltage at a secondary winding of a transformer) of the switching mode power supply is designed to have a high voltage.