Abstract: Disclosed is a control circuit of an LED lighting apparatus, which compensates for power for light emission of a lamp including LEDs. The control circuit can generate a compensation signal corresponding to change of power provided to the lamp, and uniformly maintain the power by controlling a current provided to the lamp in response to the compensation signal. Thus, the control circuit can compensate for the power change of the lamp due to a power supply environment factor in a building, region, or country or a temporarily unstable power supply environment factor, such that the lamp can emit light at uniform luminance.

Abstract: Disclosed herein are a switching mode converter and a method for controlling thereof. The switching mode converter includes a switching element, a bootstrap capacitor, and a control unit. The switching element is connected between one side of a first semiconductor device, another side of the first semiconductor device is connected to a ground, and an input power. The bootstrap capacitor is configured such that one side of the bootstrap capacitor is connected to the one side of the first semiconductor device. The control unit controls the output current or output voltage of a common charge pump provided to the switching element and the bootstrap capacitor in order to control the charging state of the bootstrap capacitor and the gate voltage of the switching element.

Abstract: Disclosed are an LED lighting apparatus and a control circuit thereof which controls the brightness of a lamp including LEDs using a dimmer. The LED lighting apparatus and the control circuit use a starting current based on a rectified voltage, in order to supply a holding current to the dimmer in a state where a lamp including LEDs is turned off.

Abstract: Disclosed are an LED lighting apparatus and a control circuit thereof which controls illumination of a lamp including LEDs using a dimmer. The LED lighting apparatus includes a flicker control unit which provides a control signal corresponding to a rectified voltage having a low angle corresponding to a preset low angle region and equal to or less than a preset level or detects an initial abnormal waveform diagram of the rectified voltage and provides a control signal corresponding to the abnormal waveform period, and controls a current path for light emission of the lamp.

Abstract: Disclosed is a control circuit of an LED lighting apparatus having a dimming function. The control circuit provides a current path corresponding to light emitting states of LED channels in response to a rectified voltage, and performs dimming by controlling a current amount of the current path in response to a dimming control signal provided as an analog signal or digital signal.

Abstract: Disclosed is a control circuit of an LED lighting apparatus, which compensates for power for light emission of a lamp including LEDs. The control circuit can generate a compensation signal corresponding to change of power provided to the lamp, and uniformly maintain the power by controlling a current provided to the lamp in response to the compensation signal. Thus, the control circuit can compensate for the power change of the lamp due to a power supply environment factor in a building, region, or country or a temporarily unstable power supply environment factor, such that the lamp can emit light at uniform luminance.

Abstract: Provided are a method of generating a message authentication code and an authentication device and an authentication request device using the method. The method includes generating a second secret key by encrypting seed data, a first secret key, and first auxiliary data using an encryption algorithm; and encrypting the seed data, the second secret key, and second auxiliary data using the encryption algorithm, wherein the encryption algorithm receives data of a preset base number of bits and encrypts the received data, and the number of bits of the second auxiliary data varies according to a difference between the number of bits of the first secret key and the number of bits of the second secret key.

Abstract: Disclosed are an LED lighting apparatus and a control circuit thereof which controls the brightness of a lamp including LEDs using a dimmer. The LED lighting apparatus and the control circuit use a starting current based on a rectified voltage, in order to supply a holding current to the dimmer in a state where a lamp including LEDs is turned off.

Abstract: Disclosed are an LED lighting apparatus and a control circuit thereof which controls illumination of a lamp including LEDs using a dimmer. The LED lighting apparatus includes a flicker control unit which provides a control signal corresponding to a rectified voltage having a low angle corresponding to a preset low angle region and equal to or less than a preset level or detects an initial abnormal waveform diagram of the rectified voltage and provides a control signal corresponding to the abnormal waveform period, and controls a current path for light emission of the lamp.

Abstract: Disclosed is a light emitting diode lighting apparatus capable of improving a power factor and temperature characteristics. The light emitting diode lighting apparatus according to a preferred embodiment of the present invention includes a light source having a plurality of light emitting diode channels and performs a current regulating operation to allow a light source to emit light. The light source uses a current path provided by current regulating to emit light.

Abstract: Disclosed is a control circuit of an LED lighting apparatus having a dimming function. The control circuit provides a current path corresponding to light emitting states of LED channels in response to a rectified voltage, and performs dimming by controlling a current amount of the current path in response to a dimming control signal provided as an analog signal or digital signal.

Abstract: A low dropout (LDO) circuit capable of controlled startup and a method of controlling the same are disclosed herein. The LDO circuit includes an amplifier, a pass element, and a startup control circuit. The amplifier receives a feedback voltage determined by an output voltage and a predetermined reference voltage, and provides a first voltage determined by the feedback voltage and the reference voltage. The pass element is connected to an input power and an output node for providing the output voltage. The startup control circuit includes a current source, and forward one of the first voltage, provided by the amplifier based on the level of the output voltage, and a second voltage, generated using the current source, to the gate of the pass element.

Abstract: An LCD driving circuit includes a first buffer configured to have a terminal for a first voltage, a terminal for a second voltage and a terminal for an intermediate voltage between the first voltage and the second voltage, and be driven in a range from the first voltage to the intermediate voltage; and a second buffer configured to have a terminal for the first voltage, a terminal for the second voltage and a terminal for the intermediate voltage, and be driven in a range from the intermediate voltage to the second voltage. The terminal for the intermediate voltage of the first buffer and the terminal for the intermediate voltage of the second buffer are connected with each other, and the first voltage is a highest voltage, the second voltage is a lowest voltage, and the intermediate voltage is in a range from the first voltage to the second voltage.

Abstract: A LED driving circuit drives a plurality of LED (Light Emitting Diode) groups, has a common voltage that is changed according to an input voltage of the plurality of LED groups, and includes a common node, a plurality of phase switches arranged between the output terminals of the plurality of LED groups and the common node, and a plurality of phase switch control units that form current flows among a corresponding LED group, a corresponding phase switch, and the common node in phase sections of the input voltage based on the common voltage and a corresponding reference voltage, the input voltage having a time-variable phase. Accordingly, the LED driving circuit can correct a power factor without using an inductor or a capacitor.

Abstract: Provided are a method of generating a message authentication code and an authentication device and an authentication request device using the method. The method includes generating a second secret key by encrypting seed data, a first secret key, and first auxiliary data using an encryption algorithm; and encrypting the seed data, the second secret key, and second auxiliary data using the encryption algorithm, wherein the encryption algorithm receives data of a preset base number of bits and encrypts the received data, and the number of bits of the second auxiliary data varies according to a difference between the number of bits of the first secret key and the number of bits of the second secret key.

Abstract: A display driving circuit includes a buffer section, an N-dot switch circuit, a charge sharing switch circuit, and a sharing voltage level control switch circuit. The buffer section buffers a plurality of pixel driving signals outputted from a plurality of DACs. The N-dot switch circuit selects paths of the plurality of pixel driving signals outputted from the buffer section in response to a first path selecting signal or a second path selecting signal that is determined depending upon a dot inversion method, and switches the paths to a plurality of output terminals. The charge sharing switch circuit shares charges among the plurality of output terminals in response to a charge sharing control signal. The sharing voltage level control switch circuit controls charge sharing between the plurality of output terminals and a voltage level upon charge sharing, in response to a sharing voltage level control signal.

Abstract: Embodiments of the present invention provide a light-emitting diode (LED) driver and method of controlling the static current of the LED driver. In some embodiments, the LED driver is configured to calculate output currents of a pulse form using a small number of parameters and adjust a gate control signal using the mean value of the output currents of a pulse form. Accordingly, the LED driver can be used to control a static current that flows through an LED array connected to a circuit on the secondary side of a transformer using a DC voltage or an AC voltage supplied to the primary side of the transformer. In some embodiments, the LED driver includes a power conversion unit, switching unit, transformer, zero current detection unit, and system control unit. In some embodiments, the system control unit is configured to adjust the gate control signal.

Abstract: The present invention introduces a device and a method for driving an LED with an improved power factor without using a voltage detector having a large amount of area and power consumption. The device for driving an LED includes a power supply unit, an LED array, and a current path select circuit. The LED array 320 is connected with the power supply unit in parallel and includes at least one LED string including LED channels LED1 to LEDn that are configured of a plurality of LEDs connected in series. The current path select circuit selects a path of current flowing from output terminals of the plurality of LED channels according to voltage levels of each of the output terminals of the plurality of LED channels.

Abstract: Embodiments of the present invention provide a light-emitting diode (LED) driver for controlling a static current supplied to an LED array connected to a secondary coil of a transformer by using the peak values of currents flowing through a power transistor, which may reside in a switching element connected to a primary coil of the transformer. In some embodiments, the LED driver is configured to control the static current that flows through the LED array using an AC voltage supplied to the primary side of the transformer. In some embodiments, the LED driver includes a power conversion unit, a switching unit, a transformer, and a system control unit. In some embodiments, the method of controlling the static current of the LED driver includes a current peak value detection step, a step output current calculation step, a static current mean value calculation step, and a gate control signal update step.

Abstract: Disclosed herein are a switching mode converter and a method for controlling thereof. The switching mode converter includes a switching element, a bootstrap capacitor, and a control unit. The switching element is connected between one side of a first semiconductor device, another side of the first semiconductor device is connected to a ground, and an input power. The bootstrap capacitor is configured such that one side of the bootstrap capacitor is connected to the one side of the first semiconductor device. The control unit controls the output current or output voltage of a common charge pump provided to the switching element and the bootstrap capacitor in order to control the charging state of the bootstrap capacitor and the gate voltage of the switching element.