Abstract: An exemplary embodiment of the present invention relates to a power supply. A power supply according to an exemplary embodiment of the present invention includes: a filter capacitor coupled to a line to which an input voltage rectified from an AC input passed through a dimmer is supplied; a discharge switch coupled to the filter capacitor through the line; and a main switch receiving the input voltage and controlling power transmission. The power supply performs input voltage control to shape the input voltage with a predetermined pattern and controls a switching operation time of the main switch.

Abstract: The present invention relates to a dimmer and an input current regulator provided in a power supply. The input current regulator includes: a bleeding circuit generating a bleeding current from an input current passed through the dimmer; a sensing circuit sensing the input current, and controlling the bleeding circuit according to a sense voltage corresponding to the input current; and a biasing circuit generating a power voltage for operation of the input current regulator during operation of the power supply. The input current includes a bleeding current and a power current supplied to the power supply.

Abstract: An exemplary embodiment of the present invention relates to a switch controller, a method for controlling a switch, and a power supply including the switch controller. According to the exemplary embodiment of the present invention, an AC input passed through a dimmer is rectified such that an input voltage is generated, and the input voltage is transmitted to the power switch. A charging current is generated using a voltage that depends on the input voltage, a zero cross-point at which the input voltage becomes zero voltage is detected using a detection voltage output from a current source, and a reference signal synchronized at the detected zero cross-point is generated.

Abstract: The present invention relates to a converter, a switch controller controlling the switching operation of a power switch in the converter, and a switch control method. An exemplary embodiment of the present invention generates a reference current corresponding to an output current of the converter and generates a control voltage that depends on the reference current. The exemplary embodiment controls an increase or a decrease of the control voltage and determines a switching frequency of the power switch according to the control voltage. The exemplary embodiment controls the on-time of the power switch by using a reference voltage determined according to a control current that depends on the reference current.

Abstract: A short-circuit sense circuit and a power supply according to an exemplary embodiment of the present invention use an auxiliary voltage, which is a both-end voltage of an auxiliary coil coupled with a predetermined turn ratio to a secondary side coil coupled to an output voltage. After termination of a start-up period, the short-circuit sense circuit samples a sense voltage, which is a voltage of a node between a first sense resistor and a second sense resistor coupled in series to both ends of the auxiliary coils and determines whether a short-circuit occurs according to a short-circuit sense signal that depends on a result of comparison between the sampled voltage and a predetermined reference voltage.

Abstract: The present invention relates to a switch control circuit, a power factor corrector including the same, and a driving method thereof. According to an exemplary embodiment of the present invention, a turn-on time of a power switch is controlled according to a zero crossing voltage to sense a voltage of both terminals of the power switch, and a turn-off time of the power switch is controlled according to a feedback voltage corresponding to the output voltage. At this time, the switching frequency of the power switch is sensed by the zero crossing voltage and the switching frequency is restricted by a predetermined threshold frequency.

Abstract: The present invention relates to a dimming angle sensing circuit and a driving method thereof. A dimming angle sensing circuit according to an exemplary embodiment of the present invention uses a zener diode. The dimming angle sensing circuit generates a comparison voltage according to a comparison result of a line voltage and a zener voltage. The line voltage is generated from rectification of an AC input passed through a dimmer. The dimming angle sensing circuit generates a sense voltage corresponding to a dimming angle of the dimmer by low-pass filtering the comparison voltage.

Abstract: The present invention relates to a switch controller and a converter including the same. The switch controller generates an oscillating voltage determining a switching frequency alternately switching a high-side switch and a low-side switch, senses a power source voltage supplied to the switch controller, and maintains the high-side switch and the low-side switch in the turn-off state in a case that the change of the power source voltage is not generated after one of the high-side switch and the low-side switch is turned off according to the oscillating voltage.

Abstract: The present invention relates to a hold-up time expansion circuit and a converter including the same. The hold-up time expansion circuit controls switching frequency of at least one switch according to the input voltage of the converter. The converter is dependent on the switching frequency that is controlled by the hold-up time expansion circuit, and controls the duty of at least one switch according to the feedback signal of the output voltage.

Abstract: An exemplary embodiment of the present invention relates to an active damper and a driving method thereof. An AC input passed through a dimmer is transmitted to an active damper through a rectification circuit. The active damper includes a damper resistor connected to the rectification circuit, a damper switch connected to the damper resistor in parallel, and a delay circuit delaying a turn-on time of the damper switch by a predetermined initial period from a turn-on time of the dimmer.

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: An exemplary embodiment of the present invention relates to a power supply. A power supply according to an exemplary embodiment of the present invention includes: a filter capacitor coupled to a line to which an input voltage rectified from an AC input passed through a dimmer is supplied; a discharge switch coupled to the filter capacitor through the line; and a main switch receiving the input voltage and controlling power transmission. The power supply performs input voltage control to shape the input voltage with a predetermined pattern and controls a switching operation time of the main switch.

Abstract: An active bleeder according to an exemplary embodiment of the present invention includes a bleed switch coupled to the input voltage and an active bleeding controller generating a bleed reference voltage according to a result of counting a period during which the input voltage is generated and switching the bleed switch according to a result of comparison between the bleed reference voltage and a bleed sense voltage corresponding to a current flowing to the bleed switch.

Abstract: An active damping circuit according to an exemplary embodiment of the present invention is applied to a power supply using an input voltage that is generated by rectifying an AC input passed through a dimmer. The active damping circuit includes: an active damper including a damper resistor coupled to the input voltage and a damper switch coupled in parallel with the damper resistor; and an active damping controller controlling a switching operation of the damper switch using a high voltage switch that generates a predetermined power voltage to control a resistance value of the active damper of a firing period of the input voltage to be higher than a resistance value of the active damper of other periods, excluding at least the firing period among a period during which the input voltage is generated.

Abstract: A dimming angle sense circuit according to an exemplary embodiment of the present invention generates a source current that depends on an auxiliary voltage corresponding to an input voltage during a turn-on period of a power switch for a period during which an input is generated according to a dimming angle. The dimming angle sense circuit generates a dimming sense voltage by mirroring the source current, and generates a sampling voltage by sampling a dimming sense voltage for every turn-on period of a power switch. The dimming angle sense circuit generates a dimming signal by supplying a dimming current to a dimming resistor and a dimming capacitor according to a result of comparison between the sampling voltage and a reference voltage.

Abstract: A short-circuit sense circuit and a power supply according to an exemplary embodiment of the present invention use an auxiliary voltage, which is a both-end voltage of an auxiliary coil coupled with a predetermined turn ratio to a secondary side coil coupled to an output voltage. After termination of a start-up period, the short-circuit sense circuit samples a sense voltage, which is a voltage of a node between a first sense resistor and a second sense resistor coupled in series to both ends of the auxiliary coils and determines whether a short-circuit occurs according to a short-circuit sense signal that depends on a result of comparison between the sampled voltage and a predetermined reference voltage.

Abstract: The present invention relates to a switch controller, a power supply including the same, and a driving method thereof. An AC input of the power supply is connected to a rectification circuit. The power supply includes a power switch to which the AC input passed through the rectification circuit flows during a turn-on period of the power switch and a switch controller detecting a half-on time point that is an intermediate time point of the turn-on period, calculating the AC current using a result of sampling a sense voltage that depends on a current flowing to the power switch during the turn-on period at the half-on time point and the turn-on period, and controlling the input current to have a reference sine wave. The reference sine wave has a sine wave that is full-wave rectified from the AC input.

Abstract: The present invention relates to an oscillator that is capable of realizing duty balancing. The oscillator determines a switching frequency of a converter converting an input voltage according to a switching operation of switches to generate an output voltage. The oscillator determines a first half cycle of a duty signal determining the switching frequency by using a reference current according to a feedback signal corresponding to the output voltage. The oscillator senses a first half cycle period by using an output of the frequency setting unit, and determines the same period as the first half cycle as a second half cycle of the duty signal after the first half cycle.

Abstract: An exemplary embodiment of the present invention relates to a switch controller, a method for controlling a switch, and a power supply including the switch controller. According to the exemplary embodiment of the present invention, an AC input passed through a dimmer is rectified such that an input voltage is generated, and the input voltage is transmitted to the power switch. A charging current is generated using a voltage that depends on the input voltage, a zero cross-point at which the input voltage becomes zero voltage is detected using a detection voltage output from a current source, and a reference signal synchronized at the detected zero cross-point is generated.

Abstract: The present invention relates to a protection circuit, a resonance converter having the same, and a protection method thereof. A resonance converter having high-side and low-side switches senses a current flowing through the low-side switch and determines a zero voltage switching failure by using a width of a current flowing to a negative direction of the low-side switch.