| 摘要 |
A lighting device including: a lighting circuit 10; a drive circuit 20; a dimmer control circuit 35; and an LPF 30, the drive circuit 20 for increasing on-time as a pulse height increases when an inputted PWM signal satisfies a first condition where a pulse height is greater than a first threshold and less than a second threshold greater than the first threshold, and making the on-time for which a switching element 25 is on when the switching element 25 turns on and off once in a burst period, constant in a second condition where the height pulse is greater than the second threshold, the LPF 30 generating a smoothed PWM signal which has a first time period satisfying the first condition and a second time period satisfying the second condition in a signal interval indicating a duty ratio, and outputting the smoothed PWM signal to the drive circuit 20. |
