| 摘要 |
A fluorescent lamp electronic ballast includes a DC to DC flyback converter, a commutator circuit, and a current sensor. The flyback converter includes a flyback transformer connected to a diode/capacitor combination, and includes a switch used to produce a flyback waveform that is rectified by the diode and results in a high voltage DC output at the capacitor. The commutator circuit receives the high voltage DC output and converts the high voltage DC output to an AC signal for operating the fluorescent lamp. The current sensor senses a DC lamp current from the output of the flyback converter and provides a current sense signal to the flyback converter. The flyback converter switch is controlled based on the current sense signal. Preferred ballasts advantageously provide a continuously dimmable lamp load, a universal type ballast for a wide range of lamp loads and combinations, and programmed start.
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