Patent ID: 7298097

Claim:
A system for driving a cold-cathode fluorescent lamp, the system comprising: a control subsystem configured to generate one or more control signals; 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: the power supply subsystem includes a first resistor, a second resistor, a first capacitor, and a transformer including a primary winding and a secondary winding; the secondary winding, the first resistor, and the second resistor are in series, the second resistor being located between the first resistor and the secondary winding, the secondary winding including a first terminal biased to a ground voltage level; the first resistor includes a second terminal and a third terminal, the second terminal being biased to the DC input voltage, the third terminal being coupled to the second resistor; the first resistor and the first capacitor are in parallel between the second terminal and the third terminal; the third terminal is associated with a first detected voltage, the first detected voltage being compared to a first predetermined voltage for determining the one or more control signals.