摘要 |
A dimmable compact fluorescent lighting device includes a safety protection circuit, an electro-magnetic compatibility (EMC) circuit, a rectification and filter circuit, a power factor correction circuit, a trigger circuit, a switching and anti-saturation circuit, a resonant circuit, and a filament pre-heating protection circuit. Alternate current from an electric main is chopped by a thyristor to form a non-sinusoidal voltage that, after passing through the EMC circuit, is subjected to rectification and filtering and fed through the power factor correction circuit for correction of the non-sinusoidal voltage and suppress of high order resonant waves, so as to supply a stable DC working voltage to a subsequent stage. Two transistors are used to alternate conduct so as to generate oscillation, which induces a high frequency sinusoidal AC voltage supplied through an electronic ballast to drive a lighting tube to emit light. |