Patent ID: 7626343

Claim:
A driving device for driving discharge lamps, comprising: a driving circuit, for transforming an inputting DC signal into a first AC signal; a transformer circuit electrically connected to the driving circuit, for transforming the first AC signal into a second AC signal to drive the discharge lamps; and a voltage detection circuit, for determining whether the second AC signal flowing through the discharge lamps is over-voltage or under-voltage, the voltage detection circuit comprising: a voltage obtaining circuit, for transforming the second AC signal flowing through the discharge lamps into a voltage signal; an over-voltage detection circuit electrically connected to the voltage obtaining circuit, for determining whether the second AC signal flowing through the discharge lamps is over-voltage according to the voltage signal, and generating an over-voltage signal if the voltage signal is over-voltage, the over-voltage detection circuit comprising a first transistor, the first transistor comprising a first control electrode electrically connected to the voltage obtaining circuit; and an under-voltage detection circuit electrically connected to the voltage obtaining circuit, for determining whether the second AC signal flowing through the discharge lamps is under-voltage according to the voltage signal, and generating an under-voltage signal if the voltage signal is under-voltage, the under-voltage detection circuit comprising a second transistor, the second transistor comprising a second control electrode electrically connected to the voltage obtaining circuit.