摘要 |
A control circuit performs ON/OFF control for a switching element so that LED current flowing in an LED unit is within a rated current range. In the case where the LED unit is lit, a voltage applied between both ends of series connection of a reactor and the LED unit becomes a first bus voltage, when the switching element is ON, and becomes a voltage lower than the first bus voltage, that is determined based on the first bus voltage and a second bus voltage, when a switching element is OFF. |