| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device capable of suppressing variation in brightness of a light source load, and to provide an illuminating fixture using the same.SOLUTION: A lighting device comprises: a power conversion circuit 1 having a switching element Q1, and supplying a desired DC output to a light source load 6 consisting of an LED element Ld1 by on-off drive of the switching element Q1; and a controller 2 switch-controlling the switching element Q1. The controller 2 sets a switching cycle T of the switching element Q1 so that an average value of an LED current Ild supplied to the light source load 6 per one cycle of the switching cycle T becomes a preset target current value α. |
