| 摘要 |
PROBLEM TO BE SOLVED: To ensure lighting of a fluorescent lamp, if used in low temperature circumstances and stabilize the lighting performance of the fluorescent lamp. SOLUTION: A converter transformer 4 supplies power required to light a fluorescent lamp to the fluorescent lamp 5. A switching transistor 3 amplifies a supplied base current at a preset DC amplification factor to be supplied to the converter transformer 4. A switching element 2 supplies a current to the base of the switching transistor 3 to control the switching transistor to be turned on/off. A current supply transistor 6a supplies a current to the base of the switching transistor 3 to complement the decrement of the DC amplification factor of the switching transistor 3. The current supply transistor 6a is controlled to be turned on/off, depending on a charge capacitor 6b to be charged or not. In this way, voltage on the fluorescent lamp, when lit, with the decrease of the DC amplification factor of the switching transistor is sufficiently complemented to provide stable lighting performance for the fluorescent lamp, if used in low temperature circumstances. |
