| 摘要 |
PROBLEM TO BE SOLVED: To implement a target ratio of a maximum current and a minimum current flowing through LEDs irrespective of the performance of an LED driver and without causing a malfunction.SOLUTION: An LED lighting device 1 includes: an LED circuit 5 including LED(1-5); bypass means 6 inserted in parallel with LED(1-5); and an LED driver 4 for supplying a current to LED(1-5) and the bypass means 6. The bypass means 6 comprises a transistor element T. For a predetermined minimum current flow through LED(1-5), the transistor element Tis operated and the LED driver 4 supplies a current amounting to the predetermined minimum current plus a flow of current through the bypass means 6. The resultant current is controlled by a switching element TR1 connected in series with LED(1-5) and the bypass means 6. |
