Patent application number | Description | Published |
20120032991 | ORGANIC LIGHT EMITTING DIODE DRIVER - There is provided an organic light emitting diode driver being capable of compensating for pixel deterioration in real time during the driving of pixels by selectively compensating pixels, requiring compensation, for the deterioration thereof. The organic light emitting diode driver includes a converting unit converting input data into compensation data used to selectively compensate for pixel deterioration depending on whether the input data has been calibrated or not; a driving unit driving pixels of a pixel unit based on the compensation data from the converting unit; and a compensating unit providing the converting unit with a deterioration compensation signal based on deterioration information obtained from a pixel driven by the driving unit. | 02-09-2012 |
20120044235 | ACTIVE MATRIX ORGANIC LIGHT EMITTING DIODE DISPLAY - There is provided an active matrix organic light emitting diode display, including a data driver converting pre-prepared correction data into an analog correction signal and generating a driving signal according to the analog correction signal, a selector selecting a charging path for programming, according to the driving signal in a preset programming period and selecting a deterioration detection path in a preset emission period, a pixel unit including an organic light-emitting diode connected between a power supply receiving power and a ground, charging a value corresponding to the correction data according to the driving signal in the programming period, and allowing current to flow to the organic light-emitting diode according to the charged value in the emission period, and an ADC detecting deterioration voltage having deterioration information of the organic light-emitting diode of the pixel unit in the emission period. | 02-23-2012 |
20120044269 | ORGANIC LIGHT EMITTING DIODE DRIVER - There is provided an organic light emitting diode driver capable of compensating for pixel deterioration in real time during the driving of pixels by selectively compensating pixels, requiring compensation, for the deterioration thereof, and precisely setting calibration data by removing an IR drop across a transistor, employed as a switch in the pixels, by calculating a difference between at least two representative values of different gray scale ranges among predetermined gray scale ranges. | 02-23-2012 |
20120044271 | ACTIVE MATRIX ORGANIC LIGHT EMITTING DIODE DISPLAY HAVING DETERIORATION DETECTION FUNCTION IN PROGRAMMING PERIOD - There is provided an active matrix organic light emitting diode display including: a data driving unit converting previously prepared correction data into a correction signal and generates a driving signal according to the analog correction signal; a pixel unit having an organic light emitting diode (OLED) between first and second power supply terminals receiving first and second powers, respectively, charging a value corresponding to the correction data according to the driving signal in a predetermined programming period, detecting the driving signal in order to detect deterioration, and allowing current to flow through the OLED according to the value charged in the predetermined programming period in a predetermined holding period; and an ADC detecting deterioration voltage corresponding to the driving signal having deterioration information of the OLED of the pixel unit in the holding period. | 02-23-2012 |
20120044360 | DETERIORATION SENSING APPARATUS FOR DISPLAY DEVICE - Disclosed is a deterioration sensing apparatus for a display device, capable of rapidly sensing deterioration by pre-charging a sensing voltage in adjacent pixels while a deterioration of a single pixel is sensed in a display device having a plurality of pixels, in, particular, an organic light emitting diode panel. | 02-23-2012 |
20120056866 | ACTIVE MATRIX ORGANIC LIGHT EMITTING DIODE DISPLAY HAVING RESET FUNCTION - There is provided an active matrix organic light emitting diode (AMOLED) display including a driver generating analog driving signals based on previously prepared driving data; a pixel unit including an organic light emitting diode connected between first and second power supply terminals receiving first and second power, respectively, charging values equivalent to the driving data according to the driving signals and simultaneously detecting the driving signals in order to detect deterioration in a preset tracking period, allowing current to flow through the organic light emitting diode according to the values charged in the tracking period in a preset holding period, and setting a reset period between the holding period and a tracking period subsequent thereto to reset the charged values; and an ADC detecting a deterioration voltage corresponding to the driving signals having deterioration information of the organic light emitting diode of the pixel unit in the tracking period. | 03-08-2012 |
20120056869 | ORGANIC LIGHT EMITTING DIODE DRIVER - There is provided an organic light emitting diode driver capable of compensating for pixel deterioration in real time during the driving of pixels by selectively compensating pixels, requiring compensation, for the deterioration thereof. The organic light emitting diode driver includes: a converter converting input data into compensation data used to selectively compensate for pixel deterioration according to whether or no the input data has been calibrated; a driver driving pixels of a pixel unit according to the compensation data from the converter; and a compensator providing the converter with a deterioration compensation signal according to deterioration information obtained from a pixel driven by the driver. | 03-08-2012 |
20120299490 | LED CIRCUIT - There is provided an LED circuit. The LED circuit may include 2N+2 light emitting units connected between a 2K−1-th node and a 2K-th node among 4N+4 (N is a natural number) nodes including a first node supplied with input voltage (K is all natural numbers equal to or smaller than 2N+2); 2N+2 switches connected between a 2K-th node and a ground (K is all natural numbers equal to or smaller than 2N+2); 2N+1 switches connected between a 2L−1-th node and a 2L+1-th node and 2N+1 switches connected between a 2L-th node and a 2L+1-th node (L is all natural numbers equal to or smaller than 2N+1); and N switches connected between the first node and a 4M+1-th node (M is all natural numbers equal to or smaller than N). | 11-29-2012 |
20120299497 | LED CIRCUIT - 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. | 11-29-2012 |
20120306396 | LED DRIVING APPARATUS AND METHOD - 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. | 12-06-2012 |
20120319609 | LIGHT EMITTING DIODE DRIVER HAVING OFFSET VOLTAGE COMPENSATING FUNCTION - There is provided a light emitting diode (LED) driver having an offset voltage compensating function compensating for an offset voltage generated at the time of driving of an LED, the LED driver including: a driving unit detecting a current flowing in an LED unit having at least one LED, as a voltage and controlling the current flowing in the LED unit according to a comparison result between the detected voltage and a reference voltage having a preset voltage level; and an offset compensating unit integrating a voltage difference between the detected voltage and the reference voltage and adding or subtracting a compensating current according to an integration result to thereby compensate for an offset. | 12-20-2012 |
20130033191 | LIGHT EMITTING DIODE DRIVING DEVICE AND METHOD THEREOF - There are provided a light emitting diode (LED) driving device allowing for an increase in an LED driving rate by discharging a charge stored in a capacitor during a certain period of time and a method thereof. The LED driving device includes: a driving unit detecting a current, as a voltage, the current flowing across an LED unit having at least one LED, controlling the current flowing across the LED unit according to a comparison result between the detected voltage and a reference voltage having a pre-set voltage level, and having a capacitor stabilizing an operation of the LED unit when the LED unit is driven; and a discharging unit discharging a charge stored in the capacitor during a pre-set discharge time when the LED unit is initially driven. | 02-07-2013 |
20130076253 | LIGHT EMITTING DIODE DRIVING APPARATUS - 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. | 03-28-2013 |
20130134901 | DRIVING APPARATUS FOR LIGHT EMITTING DIODE AND CONTROL METHOD THEREOF - There are provided a driving apparatus for a light emitting diode (LED) which may accurately display a desired color of light by adjusting a color coordinate value in accordance with an input brightness value, and a control method thereof. The driving apparatus includes a control unit receiving a brightness value and a color coordinate value of an LED desired to be controlled and controlling LED driving by adjusting the color coordinate value in accordance with the received brightness value; and a driving unit driving the LED in accordance with controlling of the control unit. | 05-30-2013 |
20130162144 | LIGHT EMITTING DIODE DRIVING APPARATUS - 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. | 06-27-2013 |
20130162164 | PWM DRIVING CIRCUIT AND PWM DRIVING METHOD - 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. | 06-27-2013 |
20130169182 | PWM CONTROL CIRCUIT, FLYBACK CONVERTER AND METHOD FOR CONTROLLING PWM - Disclosed herein are a PWM control circuit, a flyback converter, and a PWM control method. The PWM control circuit includes: a peak storing and reference signal generating unit storing a peak value of one period of a feedback signal from a secondary side output and inverting the peak signal arid outputting the inverted peak signal as a reference signal; and a PWM control signal generating unit generating a PWM control signal by using an output obtained by comparing the reference signal with a reference waveform from the peak storing and reference signal generating unit. In addition, the flyback converter including the same and the method for controlling PWM are proposed. | 07-04-2013 |
20150062977 | CIRCUIT FOR GENERATING REFERENCE SIGNAL FOR CONTROLLING PEAK CURRENT OF CONVERTER SWITCH, ISOLATED CONVERTER AND METHOD FOR GENERATING REFERENCE SIGNAL FOR CONTROLLING PEAK CURRENT OF CONVERTER SWITCH - 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. | 03-05-2015 |
20150062978 | CIRCUIT FOR GENERATING REFERENCE SIGNAL FOR CONTROLLING PEAK CURRENT OF CONVERTER SWITCH, ISOLATED CONVERTER AND METHOD FOR GENERATING REFERENCE SIGNAL FOR CONTROLLING PEAK CURRENT OF CONVERTER SWITCH - 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. | 03-05-2015 |