Patent application number | Description | Published |
20110037407 | LED LIGHT EMITTING DEVICE - The present invention relates to an LED light emitting device. An LED light emitting device includes a plurality of LED channels including a plurality of LEDs. The LED light emitting device further includes a transformer configured to convert an input voltage and supply an output voltage to the plurality of LED channels, a controller, and an LED driver. The controller controls the transformer according to a first feedback signal for interrupting power supply to the plurality of LED channels when a dimming off state in which currents are not supplied to the plurality of LED channels occurs or when a state in which the maximum channel voltage of a plurality of channel voltages corresponding to voltages applied to the plurality of LED channels, respectively, is an overvoltage and a defective state in which the plurality of LED channels include an open state are maintained during a predetermined threshold period. The LED driver generates information on the dimming off state and information on the defective state. Further, the LED driver is connected to a secondary side of the transformer, the controller is connected to a primary side of the transformer insulated from the secondary side, and the first feedback signal is generated according to the information on the dimming off state and the information on the defective state. | 02-17-2011 |
20120032611 | LED EMITTING DEVICE AND DRIVING METHOD THEREOF - The present invention relates to an LED emitting device and a driving method thereof including at least two LED channels. | 02-09-2012 |
20120104956 | LED EMITTING DEVICE - The present invention relates to an LED emitting device. | 05-03-2012 |
20120176038 | LIGHT EMITTING DIODE EMITTING DEVICE - The present invention relates to an LED emitting device. | 07-12-2012 |
20120201019 | LED EMITTING DEVICE AND DRIVING METHOD THEREOF - The present invention relates to an LED light emitting device and a driving method thereof. The LED light emitting device supplies a power supply voltage to at least two LED channels. The LED light emitting device samples channel voltages of the at least two LED channels to detect a minimum voltage from among the sampled voltages, and amplifies a difference between the detected minimum voltage and a predetermined reference voltage to generate an error amplifying signal. The LED light emitting device generates an enable signal having a duty extended by a predetermined delay period from a duty of a dimming signal for controlling light emission periods of the at least two LED channels. In this instance, the error generator is operable by the enable signal. | 08-09-2012 |
20130249406 | LED Emitting Device and Driving Method Thereof - Disclosed are an LED emitting device and driving method thereof. The LED emitting device controls an LED drive switch connected to a first end of an LED string to control an output current supplied to the LED string. The LED emitting device generates feedback information on the output voltage or the output current supplied to the LED string, and uses the output current to sense an open lamp state of the LED string. The LED emitting device uses a voltage at a first end of the LED drive switch to sense a change of the LED string to a normal state from the open lamp state. | 09-26-2013 |
20130293109 | LED DRIVER IC, DRIVING METHOD THEREOF, AND LED EMITTING DEVICE USING THE LED DRIVER IC AND THE DRIVING METHOD - The present invention relates to an LED driver IC, a driving method of the LED driver IC, and an LED light emission device using the LED driver IC. The LED light emission device includes an LED string, a power switch supplying power to the LED string, a dimming switch controlling light emission duty of the LED string, and an LED driver IC controlling switching operation of the power switch and the dimming switch. The LED driver IC senses a difference between a control electrode voltage of the dimming switch and a sense voltage generated according to a current flowing to the dimming switch, and triggers the OCP operation according to a result of comparison between the sensed voltage and a predetermined OCP reference voltage. | 11-07-2013 |
20140159678 | CABLE COMPENSATION CIRCUIT - One cable compensation circuit is connected to a shunt regulator to generate a feedback voltage corresponding to an output voltage of a power supply device. The cable compensation circuit controls cathode impedance of the shunt regulator according to the output current of the power supply device to compensate a voltage drop generated in a cable. | 06-12-2014 |
20140286056 | SWITCH CONTROL CIRCUIT, POWER SUPPLY DEVICE COMPRISING THE SAME AND DRIVING METHOD OF THE POWER SUPPLY DEVICE - The invention relates to a switch control circuit, a power supply including the same, and a method for driving the power supply. The power supply includes: a first switch; a second switch coupled in series to the first switch; a transistor coupled to a node where the first switch and the second switch are coupled; a resonance capacitor coupled between the transformer and a primary side ground and to which a resonance current flows; a sense circuit generating a first sense voltage that depends on the resonance current when the resonance current is a positive current; and a switch control circuit detecting a zero voltage switching failure by sensing the resonance current using the first sense voltage at a turn-off time of the first switch for every switching cycle of the first and second switches. | 09-25-2014 |