| 摘要 |
An apparatus for controlling the drive of a backlight unit is provided to measure brightness and color of each LED(Light Emitting Diodes) through an inner analog/digital converter of a controller and regulate the amount of current supplied to each LED to maintain the optimum color and brightness. A backlight unit(10)consists of white LEDs or red, green, and blue LEDs. An LED driver(20) controls voltages and currents applied to the LEDs according to control signals of a controller(70) to drive the LEDs. A current sensor(30) senses the amount of driving currents of the LEDs to transform the amount of driving currents into voltage values. A voltage sensor(50) senses values of voltages applied to the LEDs. A color sensor(40) senses colors of the LEDs through optical sensors, and outputs the sensed color to an analog/digital converter of the controller. When the controller receives the voltage values, which are outputted from the current sensor or the voltage sensor, to convert the voltage values into digital values, the controller compares the digital values with stored reference data to compute control values in which the sensed values approximate the reference data and controls the LED driver according to the control values so that brightness or color of each LED approximates the reference data. The controller cuts off the current outputted to the LED driver if over-voltage is determined to be applied to the LEDs through the voltage values sensed by the current sensor. |
