To reduce noise resulting from lighting driving, in an LED planar lighting system having a large number of two-dimensionally disposed LEDs.

The two-dimensionally disposed LEDs are divided into a region A and a region B to lightingly drive the LEDs for each region by PWM drive signals having different patterns. The LEDs in the region A are lightingly driven by the PWM drive signal (b) in which the position of a rising edge is fixed and a pulse width wa is controlled, and the LEDs in the region B are lightingly driven by the PWM drive signal (c) in which the position of a falling edge is fixed and a pulse width wb is controlled. Thereby, since timing for ON action or OFF action of transistors in a driving circuit shifts, switching noise disperses, and the peak of a noise level falls.

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