Patent ID: 7812548

Claim:
A system for driving a cold-cathode fluorescent lamp, the system comprising: a control subsystem configured to generate one or more control signals; and a power supply subsystem configured to receive the one or more control signals and a DC input voltage, convert the DC input voltage to an AC output voltage, and send the AC output voltage to a cold-cathode fluorescent lamp; wherein if the DC input voltage is lower than a predetermined threshold, the system for driving the cold-cathode fluorescent lamp is turned off in response to the one or more control signals; wherein: the power supply subsystem includes a voltage divider configured to convert the DC input voltage to a detected voltage; the control subsystem includes a comparator and a gate drive device coupled to the comparator; the comparator is configured to compare the detected voltage and a predetermined voltage and generate a comparison signal, the predetermined voltage being proportional to the predetermined threshold; and the gate drive device is configured to generate the one or more control signals in response to the comparison signal.