| 摘要 |
A piezoelectric ceramic light starter, which includes a power switch, a piezoelectric transformer, and a frequency tracking unit, is disclosed. The power switch connected to a pulse width modulated (PWM) harmonic signal output terminal closes when the PWM harmonic signal is in its positive period, and opens when which signal is in negative period. The piezoelectric transformer has the input terminal of its first-level coil connected to the power switch. The output terminal of the first-level coil generates a high-frequency AC signal to drive a cold cathode fluorescent light (CCFL). The frequency tracking unit is coupled to the output terminal of the CCFL. When the light starter starts, a first frequency is obtained when the CCFL is lighted and a second frequency is obtained when the CCFL is turned off. The PWM harmonic signal uses the average of the first frequency and the second frequency as the basis for output.
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