Patent application number | Description | Published |
20120074859 | DRIVER FOR LIGHT EMITTING DIODES - There is provided a driver for light emitting diodes capable of differently setting duties in which driving current flows depending on respective light emitting diode (LED) channels according to a voltage deviation between the LED channels in order to reduce heat generated due to the voltage deviation between the LED channels. The driver for LEDs includes: a detecting unit detecting a voltage drop generated in each of a plurality of LED channels receiving driving power having a preset voltage level; a converting unit converting detected analog values from the detecting unit into digital values; and a driving unit differently setting switching duties in which driving current flows in each of the plurality of LED channels according to the digital values from the converting unit to drive the plurality of LED channels. | 03-29-2012 |
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 |
20130249418 | LIGHT EMITTING DIODE DRIVING APPARATUS - There is provided a light emitting diode driving apparatus capable of uniformly maintaining current balance between light emitting diode channels. The light emitting diode driving apparatus includes: a DC to DC converting unit converting the direct current power into settable driving power; a detecting unit detecting voltage drops generated in each of a plurality of light emitting diode channels each having a plurality of light emitting diodes; a converting unit converting an analog value into a digital value; and a driving unit differentially setting duty cycles of switching signals according to the digital values from the converting unit to drive the plurality of light emitting diode channels. | 09-26-2013 |
20130249424 | LIGHT EMITTING DIODE DRIVING APPARATUS - There is provided a light emitting diode driving apparatus capable of uniformly controlling current balance between light emitting diode channels. The light emitting diode driving apparatus includes: an AC to DC converting unit converting input AC power into a preset DC driving power; a detecting unit detecting voltage drops generated in a plurality of respective light emitting diode channels each having a plurality of light emitting diodes performing a light emitting operation by receiving the DC driving power; a converting unit converting analog values detected from the detecting unit into digital values; and a driving unit differentially setting switching signal duty cycles in which a driving current is allowed to flow in the plurality of respective light emitting diode channels according to the digital values from the converting unit to drive the plurality of light emitting diode channels. | 09-26-2013 |
20140139131 | LIGHT EMITTING DIODE DRIVING APPARATUS - There is provided a light emitting diode driving apparatus, including: a power supplying unit converting input power into driving power according to a control and supplying the converted driving power to a light emitting diode channel; a driving unit controlling current flowing in the light emitting diode channel according to a pulse width modulation (PWM) dimming signal from the outside; and a controlling unit comparing a reference level set by a duty of the PWM dimming signal with a detection voltage level of the light emitting diode channel and controlling a power converting operation of the power supplying unit according to the comparison result. | 05-22-2014 |
20140160807 | POWER SUPPLY APPARATUS - There is provided a power supply apparatus capable of precisely control a primary side switching frequency at a secondary side by receiving fed-back information regarding a power state at the secondary side without a separate expensive circuit or a complicated circuit. The power supply apparatus includes: a power supplying unit having a primary side and a secondary side having different ground electrical characteristics, switching power input to the primary side, and transferring the switched power to the second side electrically insulated from the primary side to supply the power; a controlling unit provided on the secondary side and receiving fed-back information regarding a power state of the power supplying unit to control a maximum value and a minimum value of a switching frequency of the primary side; and a transferring unit transferring a control signal from the controlling unit to the primary side of the power supplying unit. | 06-12-2014 |
20150115840 | LIGHT EMITTING DIODE DRIVER - There is provided a light emitting diode driver capable of improving power efficiency by using a resistor having a low power consumption rating while controlling an LED channel so that it has constant brightness stably. The light emitting diode driver includes: a power supplying unit converting an input voltage into a predetermined driving voltage so as to supply the driving voltage to an LED channel; and a driving unit amplifying a detection voltage detected based on a current from the LED channel by a predetermined gain and controlling the current flowing through the LED channel so that the amplified detection voltage has a level equal to that of a predetermined reference voltage. | 04-30-2015 |