Abstract: A light emitting diode driving apparatus may include: a light emitting diode emitting light by receiving rectified power; a driver driving the light emitting diode based on a voltage level of the rectified power; and a controller limiting an operation of the driver based on a voltage applied to the driver and a hysteresis reference value.

Abstract: There is provided a light emitting diode driving apparatus capable of supplying a constant average current to a light emitting diode by generating a reference voltage used for driving the light emitting diode according to input power and a switching signal switching a path of a current supplied to the light emitting diode. The light emitting diode driving apparatus includes: a reference voltage generating unit generating a reference voltage set based on input power and a switching signal for supplying driving power to a light emitting diode; and a driving unit supplying the driving power to the light emitting diode according to the reference voltage.

Abstract: There is provided an apparatus for driving a light emitting diode (LED), performing switching-operation with respect to a pair of LED groups by a phase difference of 180 degrees. The apparatus includes a switching unit that alternately switches a first LED unit and a second LED unit of at least one pair of LED units emitting light by receiving rectified power, in accordance with a predetermined phase difference, a current limiting unit that limits a current flowing in the at least one pair of LED units through the switching of the switching unit, and a driving control unit that controls switching driving of the switching unit in accordance with a voltage level of the rectified power.

Abstract: Provided is a PWM driving circuit and a PWM driving method. The PWM driving circuit includes a dimmer switching unit turning on a first switch to apply a first reference signal varied according to an input voltage of a system when an output voltage level of a dimmer is a reference level or less, and turning on a second switch to apply a second reference signal, unrelated to the input voltage of the system, when the output voltage level of the dimmer is more than the reference level, an error amplification unit comparing the first reference signal or the second reference signal with an output detection signal to amplify an error and outputting an error amplification signal, and a PWM control signal generating unit comparing the error amplification signal of the error amplification unit with a predetermined reference waveform to output a PWM control signal.

Abstract: Disclosed herein is a gate driver. The gate driver according to an exemplary embodiment of the present invention includes: a first power switch sourcing current according to voltage applied by a voltage source; a second power switch connected with the first power switch in series and sinking current according to the voltage applied by the voltage source; and a speed booster receiving a voltage pulse from the outside to output peak current so as to make a turn on/off operation of the first power switch fast. As set forth above, according to the exemplary embodiments of the present invention, it is possible to improve the driving speed of the gate driver without increasing the current of the current source by further including the speed booster configured of the plurality of MOSFETs and the capacitor.

Abstract: Embodiments of the invention provide a method and a circuit for generating a reference signal for controlling a peak current of a converter switch. According to at least one embodiment, the circuit includes a squarer configured to squire an input voltage signal divided from a primary-side supply voltage of an isolated converter, and a duty ratio calculator configured to calculate a duty ratio of energy transfer to a secondary side. The circuit further includes an operator configured to generate and output a reference signal for controlling the peak current of the converter switch from a square signal of the input voltage signal using the duty ratio of energy transfer calculated by the duty ratio calculator.

Abstract: Embodiments of the invention provide a method and a circuit for generating a reference signal for controlling a peak current of a converter switch. According to at least one embodiment, a dead-zone generator configured to form a dead-zone in an input voltage signal divided from a primary-side supply voltage of an isolated converter, and a duty ratio calculator configured to calculate a duty ratio of energy transfer to a secondary side. The circuit further includes an operator configured to generate and output a reference signal for controlling the peak current of the converter switch from a dead-zone voltage signal having the dead-zone using the duty ratio of energy transfer calculated by the duty ratio calculator.

Abstract: There are provided a light emitting diode driving apparatus and a light emitting diode lighting apparatus capable of absorbing a noise current generated according to power of a phase control of a dimmer. The light emitting diode lighting apparatus includes: a dimmer controlling a phase of an alternating current (AC) power; a power supplying unit receiving the phase-controlled power from the dimmer and supplying a preset driving power; a driving unit receiving the driving power from the power supplying unit to drive a light emitting diode unit receiving the phase-controlled power; and a noise current absorbing unit suppressing an increase in a voltage level of the driving power supplied to the driving unit by the phase-controlled power.

Abstract: There is provided a light emitting diode driving apparatus charging and discharging a valley fill power by comparing a voltage level of rectified power with a preset reference voltage. The light emitting diode driving apparatus includes a rectifying unit rectifying input AC power, a charging and discharging unit comparing a voltage level of power rectified by the rectifying unit with a preset reference voltage to charge and discharge the rectified power depending on the comparison result, and a driving unit driving a light emitting diode depending on the power rectified by the rectifying unit and a voltage discharged from the charging and discharging unit.

Abstract: Disclosed herein is a light emitting diode (LED) driving apparatus including: at least one energy storages connected in series with each other; a plurality of LEDs each connected in parallel with each of the energy storages; and a switching control unit selectively connecting the at least one energy storages according to a level of applied voltage to charge/discharge voltage in/from the selected energy storages and control driving of the LEDs by the charging/discharging operation. Therefore, it is possible to easily drive the LEDs without a converter.

Abstract: There is provide a light emitting diode lighting apparatus capable of being generally used in various kinds of dimmer, the apparatus including: a dimmer varying waveforms of input power according to a dimming signal; a bleeder adjusting a bleeding current under control; a controller comparing a latching current of the dimmer with the bleeding current of the bleeder to control the amount of the bleeding current; and an LED driver receiving a current other than the bleeding current flowing through the bleeder from among the currents from the dimmer to driver a light emitting diode (LED).

Abstract: There are provided an LED driving apparatus and an LED driving method thereof. The LED driving apparatus includes: a light emitting unit including one or more LEDs, a rectifying unit rectifying an input signal to generate a first signal; a signal conversion unit inverting a waveform of a first signal to generate a second signal; and an operation unit arithmetically operating the first and second signals. A plurality of AC signals each having a different waveform are arithmetically operated to generate a signal having a small amount of a ripple component, and an LED is driven by the signal, thus preventing a lifespan of the LED from being shortened by omitting a smoothing electrolytic capacitor, one of main causes shortening the lifespan of an LED driving circuit.

Abstract: Provided is an LED driving apparatus. The LED driving apparatus includes a plurality of LED groups each comprising one or more diodes, a switch group comprising a plurality of switch units connected respectively to the LED groups to drive the connected LED group when a control signal is activated, and a switch controlling unit configured to compare an input voltage of the LED groups with an output voltage of the LED groups, calculate a comparison value, and generate the control signal according to the comparison value. Accordingly, the LED driving apparatus drives the LED groups selectively according to the difference between the input voltage of the LED group and the output voltage of the LED group, thereby overcoming the problem of heat generation by forward voltage distribution.

Abstract: There is provided an LED circuit including a light emitting unit including a plurality of light emitting diodes; and a switching unit switching to apply only positive voltage of an AC power supply to an anode of the light emitting unit. Through this, the LED circuit can reduce complexity of a driving circuit. Further, lifespan and efficiency of the LED circuit may be improved since an electrolytic capacitor and a bridge circuit are not used. Further, any one light emitting diode may be prevented from determining the lifespan of all of the light emitting diodes since all of the light emitting diodes are driven at all times, thereby improving the lifespan of the light emitting diode.

Abstract: A fixture-compatible, dimmable illumination driving apparatus including: a rectifying unit rectifying a phase-controlled waveform of an alternating current (AC) power; a comparing unit comparing an output waveform of the rectifying unit with a first voltage according to a preset reference clock; a reference voltage generating unit generating a reference voltage corresponding to the number of high signals higher than the first voltage among outputs of the comparing unit during one cycle of the output waveform; and a pulse width modulation (PWM) signal generating unit generating a PWM signal from the reference voltage and a feedback voltage.

Abstract: There is provided an apparatus for driving a light emitting diode (LED), performing switching-operation with respect to a pair of LED groups by a phase difference of 180 degrees. The apparatus includes a switching unit that alternately switches a first LED unit and a second LED unit of at least one pair of LED units emitting light by receiving rectified power, in accordance with a predetermined phase difference, a current limiting unit that limits a current flowing in the at least one pair of LED units through the switching of the switching unit, and a driving control unit that controls switching driving of the switching unit in accordance with a voltage level of the rectified power.

Abstract: There is provided a light emitting diode driving device capable of preventing a number of switches from being turned on simultaneously when a plurality of light emitting diodes are respectively driven using a plurality of switches, the light emitting diode driving device, including: a light emitting diode unit having a plurality of light emitting diodes connected to one another in series and emitting light through receiving rectified power; and a driving unit having a plurality of drivers driving the plurality of light emitting diodes of the light emitting diode unit, respectively, wherein each of the plurality of drivers selects a maximum voltage from among a plurality of detection voltages with respect to current flowing in at least one light emitting diode corresponding thereto and compares the maximum voltage with a preset reference voltage to thereby drive the corresponding light emitting diode.

Abstract: Disclosed herein is a gate driver having a function of preventing shoot-through current. The gate driver having a function of preventing shoot-through current includes: a first power switch sourcing current according to voltage applied by a voltage source; a second power switch connected with the first power switch in series and sinking current according to voltage applied by the voltage source; and a shoot-through current preventing circuit preventing the occurrence of shoot-through current in first and second power switches at the time of driving of the first and second power switches. According to the present invention, the shoot-through current preventing circuit configured of the plurality of PMOSs and NMOSs can prevent the shoot-through current from occurring in the power transistor of the output terminal at the time of the driving of the gate driver, thereby preventing the unnecessary power consumption and the occurrence of ground noise.

Abstract: Disclosed herein is a gate driver. The gate driver according to an exemplary embodiment of the present invention includes: a first power switch sourcing current according to voltage applied by a voltage source; a second power switch connected with the first power switch in series and sinking current according to the voltage applied by the voltage source; and a speed booster receiving a voltage pulse from the outside to output peak current so as to make a turn on/off operation of the first power switch fast. As set forth above, according to the exemplary embodiments of the present invention, it is possible to improve the driving speed of the gate driver without increasing the current of the current source by further including the speed booster configured of the plurality of MOSFETs and the capacitor.

Abstract: The present invention relates to an average current controller, an average current control method and a buck converter using the average current controller. The average current controller includes a first comparator for generating a high H signal, a multivibrator for generating a TAVG pulse signal by receiving a high H signal outputted from the first comparator, a timing generator for generating a signal CH_ON to charge/discharge a capacitor by using at least the TAVG pulse signal, an integrator circuit unit for charging/discharging the capacitor, a second comparator for outputting a corresponding signal, an up/down counter for increasing or decreasing a counting value and a digital/analog converter for outputting by converting an output (digital signal) of the up/down counter into an analog signal.