| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize a discharge lamp lighting device having a high communication speed even when a photo coupler of the same performance is used by reducing the volume of data transmitted to and received from a setting part side. <P>SOLUTION: A discharge lamp 17 is lighted by lowering a DC voltage of a power supply 11 through use of a converter 12, by converting the lowered DC voltage into an AC voltage through use of an inverter 15, and then by generating a high voltage through use of a lamp starting circuit 16. In a control circuit 20, a switching signal "a" and a driving signal "d" that alternatively switches on and off the switch elements SW1, SW2, SW3, SW4 are generated, respectively. The switching signal "a" is generated based on the duty of a control signal SCI supplied to an interface circuit 19, and the driving signal "d" is generated at the timing at the rising edge of the control signal SCI including information such as lighting-on, lighting-off and dimming, respectively. In the control circuit 20, a flag signal FG different in the duty is outputted based on the temperature information "e" from the lamp lighting control part 100. Based on this flag signal FG, a state of the lamp lighting control part 100 is grasped on the setting part 200 side. <P>COPYRIGHT: (C)2009,JPO&INPIT |
