| 摘要 |
PROBLEM TO BE SOLVED: To provide a lamp lighting circuit preventing flicker in a simple structure during lighting of a plurality of lamps. SOLUTION: On/off switching of power source voltage supplied to a lamp LP1 is carried out by a MOSFET 71, and on/off switching of power source voltage supplied to a lamp LP2 is carried out by a MOSFET 72. Here, a PWM signal for carrying out the on/off switching of the MOSFET 71 is outputted at an oscillation frequency f1 by an oscillation circuit 51 and a driving circuit 61, and at the same time, a PWM signal for carrying out the on/off switching of the MOSFET 72 is outputted at an oscillation frequency f2 by an oscillation circuit 52 and a driving circuit 62. A difference of the oscillation frequency f1 outputted from the oscillation circuit 51 and the driving circuit 61 and that f2 outputted from the oscillation circuit 52 and driving circuit 62 is to be 50 Hz or more. COPYRIGHT: (C)2008,JPO&INPIT |
