| 摘要 |
A circuit for driving cold cathode tubes and external electrode fluorescent lamps uses only 19-26 watts of power. A steady state square wave oscillator generator sets a running frequency for the circuit. A high voltage inductor or high voltage/high frequency transformer in combination with a current limiting capacitor, the lamp and two low resonance value capacitors in series are set and tuned to the oscillation frequency to achieve resonance with the oscillator. The circuit requires an input that has been capacitively and inductively filtered to eliminate harmonic noise in and out of the input line. A thermal shutdown feedback circuit monitors temperature of the circuit. Further, a non-inductive or non-capacitive loading lamp detection feedback and a lamp disconnect driver eliminates false disconnects at start up due to cold bulbs and allows all lamps running on the circuit to continue operation if one is disconnected.
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