| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a resonant inverter circuit which is operated continuously from an open circuit state to a short circuit state in an output terminal of a lamp. <P>SOLUTION: The continuous mode electronic ballast (10) for making an HID lamp (28) operate includes an inverter circuit (12), constituted so as to generate a control signal according to a first embodiment. The resonance circuit (14) is composed so as to be connected operably to the inverter circuit and the lamp and to generate a resonant voltage, in response to the reception of the control signal generated by the inverter circuit. A clamping circuit (16) is operably connected to the resonant circuit so as to both limit the end voltages of the resonant circuit and to protect constituent elements of the ballast. A doubling circuit (82) is connected operably to the resonant circuit and increases the voltage clamped by the clamping circuit to a sufficient value, capable of starting up the lamp. The clamping circuit and the doubling circuit are made to cooperate with each other so as to facilitate the continuous start of the lamp. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
