| 摘要 |
<p>A modified electronic ballast for a fluorescent lamp comprises a filter rectifying circuit (10), a frequency converting circuit (20), lamp tubes (LA), starter (TP) and a first capacitor (C9-1). Both output ends of the frequency converting circuit (20) are each electrically connected to two filament electrodes at one side of the lamp tube (LA), two ends of the starter are each electrically connected to the two filaments electrodes at the other side of the lamp tube (LA), the first capacitor (C9-1) is connected to the two filament electrodes of the lamp tube (LA) in a manner of connection to the starter in parallel. The preheat starting for the tube (LA) can be performed in short-circuit means, and the hopping open-circuit can make the induction voltage high enough, allowing the lamp tube (LA) to have functions both of fair preheat starting and protection against abnormal working.</p> |
