| 摘要 |
PURPOSE:To improve light output securing a certain degree of lamp life by lighting a fluorescent lamp by supplying lamp current of a frequency number of more than 20kHz and which obtains 150% light flux or rated light flux. CONSTITUTION:A pair of MOSFET's 101, 102 are connected in series with each other between output terminals of a DC power source 2, and the FET's 101, 102 compose a serial type inverter. Between the output terminals of an output coil 104 of an output transformer 103 is connected a resonance capacitor 105 for generating high frequency power of 45kHz, for example, by resonance with a leakage inductance of the transformer 103. Between both terminals of the output coil 104 are connected fluorescent lamps 3, 4 in series to each other. A generation control part 6 changes the frequency number of an output signal corresponding to PWM signals inputted from external to terminals 61, 62 to control switching of the FET's 101, 102. The lamps 3, 4 are thus lighted by 150% light flux, thereby light output can be improved while securing a certain degree of lamp life. |
