| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting circuit for lighting an LED stably. SOLUTION: A direct-current power supply circuit 120 generates a direct-current power supply voltage. An inverter circuit 130 generates a rectangular wave voltage. A resonance circuit 140 generates an alternating-current voltage by the resonance of a choke coil L41 and a resonance capacitor C42. A rectification circuit 150 generates a direct-current load voltage. The inverter circuit 130 is arranged so that a frequency of a rectangular wave voltage generated in a lighting start period is a frequency farther from a resonant frequency of the resonance circuit 140 than a frequency of a rectangular wave voltage generated in a continuous lighting period. COPYRIGHT: (C)2011,JPO&INPIT |
