Fairchild Korea Semiconductor Ltd.

Hak-Hee Lee

Jae-Soon Choi

Eung-Woo Lee

Byunghak Ahn

Il-Young Jung

Seunguk Yang

Dong-Hun Lee

Chan Son

Jin-Hwa Chung

The present invention relates to an LED emitting device. The LED emitting device includes: a converter converting an input voltage according to a switching operation of a power source switch to generate at least two output voltages; an LED panel unit including a plurality of LED channels having a plurality of LEDs; a micom board operated by a first output voltage among the at least two output voltages to control the operation of the LED emitting device; a regulator converting a second output voltage among the at least two output voltages into a voltage suitable for the operation of the LED panel unit; and a multi-channel control unit controlling an operation of the regulator according to a lowest minimum voltage among the voltages of a plurality of LED channels and receiving the first output voltage to generate a first feedback voltage VF

LED emitting device

An LED light emitting device includes LED channels with LEDs, a transformer that converts an input voltage and supply an output voltage to the 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 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 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.

LED light emitting device

An inverter according to exemplary embodiment of the present invention generates a plurality of feedback voltages corresponding to driving voltages of discharge lamps. The inverter generates a first minimum voltage having a smaller feedback voltage of a plurality of feedback voltages and compares the first minimum voltage and a short circuit reference voltage to determine a short circuit of at least two discharge lamps. Also, the inverter generates a plurality of feedback voltages corresponding to driving currents of a plurality of discharge lamps, generates a second minimum voltage having a smaller feedback voltage of a plurality of the feedback voltages, and compares the second minimum voltage and an open circuit reference voltage to determine the open circuit of the at least two discharge lamps.

Inverter device and driving method thereof

The present invention relates to an inverter and a lamp driver having the same. The inverter includes a first switch having a first body diode, a second switch having a second body diode, a transformer including a first side coil in which a first current and a first voltage are generated according to switching operations of the first switch and the second switch and a second side coil having a predetermined winding ratio with respect to the first side coil, and a controller for controlling each switching operation of the first switch and the second switch. The controller turns on one of the first switch and the second switch corresponding to one of the first body diode and the second body diode, and a current flows through the first switch and the second switch during a dead time.

Inverter and lamp driver including the same

A load driver includes an inverter and an inverter driver. The inverter converts an input voltage into a driving voltage of a discharge lamp using at least one first switch for switching according to a duty ratio, and the inverter driver controls the inverter. The inverter driver controls the duty ratio using a voltage of a capacitor and a control signal having a waveform that is repeated with a predetermined frequency. The capacitor is charged and discharged by a current corresponding to a difference between a feedback voltage corresponding to a current flow to the discharge lamp and a reference voltage. Such inverter driver controls to gradually increase the output voltage of the inverter in the soft start period by setting the voltage of the capacitor as a voltage corresponding to the control signal.

Growing community of inventors

Bucheon, South Korea

Hak-Hee Lee