| 摘要 |
PURPOSE: To solve some troubles of an inverter apparatus attributed to a wire-wound transformer by using a piezoelectric transformer and provide a cold-cathode tube drive apparatus for which the piezoelectric transformer is used and which can carry out lighting of a cold-cathode tube and modulating the light. CONSTITUTION: An inverter apparatus is an apparatus having a cold-cathode tube CFL1 and a lighting circuit to light the cold-cathode tube and for which a piezoelectric transformer T1 is used and a voltage booster chopper is installed in the prior stage to a semi-E-class voltage resonance inverter for the purpose to complement the voltage boosting rate of the piezoelectric transformer, the inverter and a power switch element of a chopper are composed of the same power switch element Q1, and the cold-cathode tube is controlled at constant current by a single voltage resonance control ICIC1. Since a lighting circuit is composed by using the piezoelectric transformer, the number of part items can be lessened and the apparatus can be miniaturized and at the same time the manufacturing cost is lowered. Furthermore, the lighting frequency of a discharge lamp can be heightened by increasing the resonance frequency of the piezoelectric transformer and consequently discharge efficiency can be improved. |
