Semiconductor Components Industries, LLC

Fairchild Korea Semiconductor Ltd.

Fairchild Semiconductor Corporation

SangCheol Moon

Gwanbon Koo

Chenghao Jin

Bonggeun Chung

Jintae Kim

Hangseok Choi

BongGeun Chung

Laszlo Balogh

GwanBon Koo

Jason Guo

A planar magnetic element includes a pair of cores, a first winding layer disposed between the pair of cores and including a first winding coupled between a first terminal and a second terminal, and a plurality of second winding layers disposed between the pair of cores and including second windings coupled between a third terminal and a fourth terminal, wherein the first winding layer may be disposed between the plurality of second winding layers.

Planar magnetic element

A buck converter includes a power switch having a first end to receive an input voltage, and a soft start circuit configured to compensate a soft start voltage during a soft start time period according to a result of comparing a feedback voltage corresponding to an output voltage of the buck converter and an input detection voltage corresponding to the input voltage. The buck converter controls switching of the power switch using the soft start voltage.

Soft-start circuit and buck converter comprising the same

Soft-start circuit for buck converter control

An AC-DC converter includes a main switch that is controlled according to an input AC line voltage. The main switch is allowed to be switched when a level of the input AC line voltage is within a regulation band, and is prevented from being switched when the level of the input AC line voltage is not within the regulation band. The regulation band can be dynamically adjusted based on load condition. The AC-DC converter can be a buck, boost, or buck-boost converter.

Input AC line control for AC-DC converters

Provided are an input voltage detection circuit and a power supply including the same. The power supply includes a rectifier circuit configured to generate a line input voltage by rectifying an alternating current (AC) input. The input voltage detection circuit which is applied to the power supply generates a peak sensing voltage that indicates a predetermined peak area defined around a peak of the line input voltage, generates a peak detection signal that indicates the peak of the line input voltage based on a center of the peak sensing voltage, and generates an input sensing voltage corresponding to the line input voltage by being synchronized with the peak detection signal. The power supply may control a switching period according to the input sensing voltage.

Input voltage detection circuit and power supply including the same

A buck converter includes a power switch having a first end to receive an input voltage, a synchronous switch connected between a second end of the power switch and the ground, an inductor having a first end connected to the other end of the power switch, and a switch control circuit configured to turn off the synchronous switch when a zero voltage delay time passes after an inductor current flowing through the inductor reaches a predetermined reference value, calculate a dead time based on the input voltage and the zero voltage delay time, and turn on the power switch when the dead time passes following the turn-off time of the synchronous switch.

Switch control circuit and buck converter comprising the same

A wireless power transmission system according to an exemplary embodiment of the present invention transmits power from a primary side to a secondary side, and includes: a secondary coil provided at the secondary side; a capacitor and a control switch electrically coupled in series between lateral ends of the secondary coil; and a regulation controller controlling a switching operation of the control switch according to a result of comparison between a control signal synchronized by a frequency at the primary side and a feedback signal corresponding to an output of the wireless power transmission system.

Wireless power transfer system and driving method thereof

A buck converter includes a power switch having one end to which an input voltage is transferred, a synchronous switch connected between the other end of the power switch and the ground, an inductor having an end connected to the other end of the power switch, and a switch control circuit configured to calculate a zero voltage delay time based on at least an ON time of the power switch and a delay time. The delay time is determined based on the inductor and parasitic capacitors of the power switch and the synchronous switch.

Switch control circuit and buck converter including the same

Provided is a power factor correction circuit including an inductor having one end to which an input voltage is applied; a power switch connected between another end of the inductor and the ground, and configured to control an output of the power factor correction circuit; and a power factor correction controller configured to calculate a duty of the power switch on the basis of an output detection voltage corresponding to the output and an inductor current flowing through the inductor, calculate conduction-period information regarding a conduction period in which the inductor current flows in one switching cycle of the power switch, and compensate the calculated duty on the basis of the conduction-period information.

Power factor correction circuit with calculated duty compensation and driving method thereof

Provided is a buck converter. The converter includes a power switch configured to receive and switch an input voltage and convert the input voltage into an output voltage, and a switch control circuit configured to generate a signal having a frequency synchronized with the input voltage, compensate for the signal by using an edge threshold voltage in an edge area of the signal according to at least one of a load state and the input voltage, and control switching of the power switch by using a result of comparing the signal with a band voltage corresponding to the output.

Switch control circuit and converter including the same

A wireless power transmission system according to an exemplary embodiment of the present invention includes: a source coil at a primary side; a load coil at a secondary side; and at least two intermediate coils coupled with each other in an insulated manner with a predetermined turn ratio with respect to the source coil. An effective inductance of the source coil is increased by the at least two intermediate coils and thus a coupling coefficient between the source coil and the load coil is increased.

Wireless power transfer system

A power supply apparatus and a driving method thereof are disclosed The power supply apparatus includes: a dimmer controlling externally input power; a converter including a switch, and converting an output of the dimmer according to a duty of the switch and supplying a first current to a load; a dimming feedback unit receiving a first voltage corresponding to the first current, and having a finite gain in a DC state; and a controller controlling the duty of the switch according to an output of the dimming feedback unit. A duty of the switch is controlled according to an output of such a dimming feedback unit so that a dimming operation is performed.

Growing community of inventors

Daejeon, South Korea

SangCheol Moon