| 摘要 |
PURPOSE: To obtain a power source for a control circuit without using a power resistor from a power source voltage by providing a series circuit of the main inductor and the auxiliary inductor of a chopper, and inputting the electromagnetic energy stored in the auxiliary inductor to an auxiliary capacitor through the auxiliary diode. CONSTITUTION: A commercial power source 1 is connected to a rectifier 2, the output of the rectifier 2 is inputted to a stepping-up chopper 3, and its output is inputted to a fluorescent lamp 7 in an inverter 4. A main inductor 11 and an auxiliary inductor 12 are connected to the chopper 3. When the MOSFET 21 of the chopper 3 is turned on, electromagnetic energy is stored in the inductor 11. When the MOSFET 21 is turned off, the energy stored in the inductor 12 is charged in the capacitor 30 to step up the output voltage. On the other hand, the energy stored in the inductor 12 is charged in the capacitor 34 to supply the power necessary for the operation of a chopper controller 5. |
