Lg Display Co., Ltd.

Jun-Hyeok Yang

Jae-Won Han

Hong-suk Kim

Joung-Woo Lee

Jae-Hong Park

A method and a circuit for synchronizing input and output synchronizing signals are disclosed. The method for synchronizing input and output synchronizing signals includes detecting an Nth (N is a positive integer) input period of the input synchronizing signal, determining whether the detected Nth input period is the same with a prior (N&#x2212;1) the output period of the output synchronizing signal, detecting a difference between an end time of the (N&#x2212;1)the output period and an end time of the Nth input period, if the detected Nth input period is not the same with the (N&#x2212;1)the output period, operating the detected difference with the Nth input period, and setting the operated value as an Nth output period, and generating and outputting the output synchronizing signal having the set Nth output period.

Method and circuit for synchronizing input and output synchronizing signals, backlight driver in liquid crystal display device using the same, and method for driving the backlight driver

Disclosed is checking a drive state of a backlight lamp of a liquid crystal display device and notifying to an external entity whether it is normally driven in which level or is difficult to be normally driven. The apparatus for displaying a drive state of a backlight in a liquid crystal display device includes an inverter for converting an inputted DC voltage into an AC voltage of a certain level, and outputting the same to a backlight lamp; a drive voltage detecting unit for detecting a drive voltage supplied to the backlight lamp from the inverter and outputting a detected signal according to the detected drive voltage; a drive current detecting unit for detecting a tube current of the backlight lamp and outputting a detected signal according to the detected tube current; a drive voltage control/drive state signal output unit for checking a drive state of the backlight lamp based on the two detected signals, and controlling the drive voltage outputted from the inverter based on the checked result as well as outputting a drive state signal for indicating the drive state; and a lamp drive state indicating unit for indicating in which drive state the backlight lamp is driven according to the drive state signal.

Apparatus and method for displaying drive state of backlight in liquid crystal display device

A backlight unit for a liquid crystal display device includes: at least one light source; and an inverter circuit part including a dimming test portion generating a dimming signal and turning ON/OFF the at least one light source using the dimming signal.

Growing community of inventors

Goyang-si, South Korea

Jun-Hyeok Yang