| 摘要 |
PROBLEM TO BE SOLVED: To provide a light source lighting device capable of performing the dimming control accurately depending on the duty ratio of an external PWM signal, and to provide an illuminating device using the same.SOLUTION: A light source lighting device 1 includes a lighting circuit 2, a dimming circuit 3, and a control circuit 4. The dimming circuit 3 receives a first PWM (Pulse Width Modulation) signal for adjusting the amount of light of a light source, and generates a second PWM signal according to the first PWM signal. The control circuit 4 receives an input of the second PWM signal and outputs a signal for dimming/lighting control to the lighting circuit. The control circuit 4 measures at least one of the on period and off period of the second PWM signal, and outputs a signal to the lighting circuit based on a third PWM signal produced by adding or subtracting a correction value to or from the on period and off period of the second PWM signal, so as to substantially match the duty ratio of the first PWM signal. |
