| 摘要 |
<p>An electric lighting device includes a voltage-fed inverter configured to receive a DC voltage and produce an AC lamp voltage. A lamp load is coupled to the AC lamp voltage and this lamp load includes a gas discharge lamp and a sensing capacitor coupled in series with the gas discharge lamp. A failing gas discharge lamp places a DC bias voltage on the sensing capacitor. A voltage regulator is included that is configured to receive the AC lamp voltage, generate a reference voltage and adjust the inverter frequency to regulate the AC lamp voltage at a generally constant level corresponding to the reference voltage. An EOL protection circuit is included that is configured to receive the DC bias voltage and adjust the reference voltage such that the AC lamp voltage is lowered when a magnitude of the DC bias voltage exceeds a predetermined threshold voltage.</p> |
