| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a small lighting system with a reduced number of components. <P>SOLUTION: The lighting system comprises a direct current power supply circuit 3 for outputting a predetermined direct current voltage, an inverter circuit 4 for converting the direct current voltage outputted from the direct current power supply circuit 3 into a high frequency voltage, and a controlling integrated circuit 6 for controlling a switching element Q1 of the direct current voltage circuit 3 and switching elements Q2, Q3 of the inverter circuit 4. The controlling integrated circuit 6 has an inverter driver circuit 63 and an inverter control part 62 for controlling an ON/OFF time of each of the switching elements Q2, Q3 of the inverter circuit 4, a timer circuit 64 for outputting oscillation signals to count the time at constant intervals, and a light control part 65 for counting a lighting time of a discharging lamp La1 by counting an oscillating number of the oscillation signals from the timer circuit 64, and for controlling the ON/OFF time of each of the switching elements Q2, Q3 of the inverter circuit 4 to vary a light control ratio of the discharging lamp La1 according to the counted lighting time. <P>COPYRIGHT: (C)2012,JPO&INPIT |
