BACKLIGHT DRIVING CIRCUIT AND BACKLIGHT CONTROL SIGNAL GENERATING METHOD THEREOF

摘要

A backlight driving circuit for a display apparatus and a method for generating a backlight control signal are provided to reduce the consumption power for light-emitting the backlight by the newly produced backlight control signal. A sampling member(12) detects the first duty ratio of the first PWM(Pulse Width Modulation) signal inputted from the outside. The first PWM generating member(14) generates the second PWM signal having the second duty ratio. A calculating member(16) calculates the third duty ratio by calculating the first and the second duty ratio. The second PWM generating member(18) generates the third PWM signal according to the third duty ratio. The outside circuit is a TV or a computer system. The sampling member includes a clock generating member for outputting a sampling clock. A count member counts the sampling clock applied during the first period of the first PWM signal. A duty ratio calculating member calculates and outputs the first duty ratio according to the counting result.