Abstract: A power supply device according to the present invention includes: a filter capacitor coupled to a line to which an input voltage that is 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 device performs input voltage control for shaping the input voltage with a predetermined pattern using the discharge switch.

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: A primary-side regulation (PSR) power supply device according to the invention includes: a power switch; an auxiliary wiring from which an auxiliary voltage that depends on an output voltage is generated during a turn-off period of the power switch and being provided in a primary side; a clamping circuit clamping a voltage corresponding to the auxiliary voltage to a predetermined voltage; a voltage follower decreasing the sense voltage according to a decrease of the auxiliary voltage; and a switch control circuit controlling a switching operation of the power switch by using the sense voltage.

Abstract: According to the exemplary embodiments, a short-circuit of a sense resistor is detected according to a result of comparison between a sense voltage and a reference voltage at a time based on at least one of a period set based on an input sense voltage and a turn-on time of a power switch. A blanking period is set based on the input sense voltage in a current mode, and a short-circuited resistor detection period is set based on the input sense voltage.

Abstract: A power supply includes a power switch and a switch control circuit controlling a switching operation of the power switch using a comparison voltage generated according to an output, determining a clamping voltage by sensing an input voltage during a start-up period, and clamping the comparison voltage to the clamping voltage during the start-up period.

Abstract: A switch control circuit that controls a switching operation of a power switch includes: an input current calculator generating an input sense voltage by integrating a sense voltage that indicates a switching current flowing to the power switch for a switching period unit of the power switch; and an input current comparator generating a gate-off signal according to a result of comparison between the input sense voltage and a predetermined input reference voltage, wherein the power switch is turned off according to the gate-off signal.

Abstract: An active damper and a power supply according to exemplary embodiments include: a damper resistor coupled to an input voltage; a damper switch coupled in parallel with the damper resistor; and a capacitor to which a reset current generated by a leading edge of the input voltage flows. The damper switch is turned off by the reset current.

Abstract: Provided is regulation of a line current. The regulation of the line current includes comparing a reference voltage with a line sensing voltage to generate a feedback voltage, and controlling a switching operation of a power switch using the feedback voltage. The reference voltage may be a voltage having a constant level, a voltage which varies according to an output current, or a voltage which follows a sine wave to compensate a power factor. Provided is sensing of an output current. The sensing of the output current includes sensing the output current using a feedback voltage corresponding to a voltage between both terminals of an inductor connected to a power switch, a peak of current flowing through the power switch, and a switching cycle of the power switch.

Abstract: A start-up circuit includes a first zener diode and a second zener diode coupled to each other, a first switch configured to perform a switching operation according to at least one of a first zener voltage of the first zener diode and a second zener voltage of the second zener diode, at least one second switch coupled to the first zener diode and the second zener diode, and a driving unit configured to drive the at least one second switch using a driving signal of a power switch which controls power supply.

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 wave.

Abstract: The present invention relates to a switch controller, a power supply including the same, and a method for driving the same. An AC input of the power supply is connected to a rectification circuit. The power supply includes a power switch to which an input current passed through the rectification circuit flows during an on-period and a switch controller, the switch controller detects a half-on time point that is the intermediate time point of the on-period, detects a sense voltage that is determined by a current flowing to the power switch during the on-period at the half-on time point, generates a modulation wave by controlling a reference wave according to the detected voltage, and controls switching operation of the power switch according to the modulation wave.