Magnachip Semiconductor, Inc.

Young-gi Ryu

Hyun-Jung Kim

Joo-han Yoon

A light-emitting diode (LED) driver circuit and a light apparatus including the LED driver circuit are provided. The light apparatus includes an LED array, an input unit, a rectifier, and a control circuit. The LED array includes LED devices connected to one another in series. The input unit receives an alternating current (AC) power source. The rectifier circuit full-wave rectifies the received AC power source signal and supplies the full-wave rectified AC power source signal to the LED array. The control circuit selectively lights the LED devices according to a voltage level of the full-wave rectified AC power source signal. The control circuit includes switching elements and comparators. The switching elements selectively force nodes between the LED devices to be grounded. The comparators turn-on one of the switching elements according to the voltage level of the full-wave rectified AC power source signal.

LED driver circuit and light apparatus having the same in

A backlight driving circuit that provides backlight to a display panel of a display apparatus includes a power supply unit configured to supply power, a converter configured to convert and output a voltage of the supplied power, a light-emitting module supplied with the outputted voltage from the converter and providing the backlight, a switch connected to an output terminal of the light-emitting module and controlling an operation of the light-emitting module, a feedback resistor connected to an output terminal of the switch and sensing a voltage of a current flowing in the light-emitting module, a short-circuit sensing resistor connected between a ground of the power supply unit and a ground of the feedback resistor, and a short-circuit sensor configured to sense a voltage value of a current applied to the feedback resistor or the short-circuit sensing resistor according to whether the switch is switched on or off.

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Cheongju-si, South Korea

Young-gi Ryu