摘要 |
A drive circuit performing time division drive of a piezoelectric transformer realizes a wide dimmer control range and prevention of blinking at a frequency visually perceptible upon lacking of output, prevention of blinking of a load at the frequency visually perceptible before initiation of turning ON of the load, and suppression of heating of parts of the drive circuit at no load operation. Time division frequency signals used in time division driving are generated in a plurality of kinds in a dimmer control circuit. The generated plurality of kinds of time division frequency signals is selected depending upon the condition of the load and a dimmer condition of the piezoelectric transformer and thus to select optimal time division drive frequency or simultaneously with a plurality of time division drive frequency, the piezoelectric transformer is driven.
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