Abstract: A CCFL (cold-cathode fluorescent lamp) driving system for multiple CCFL loads includes a transformer, a CCFL circuit, and a controlling circuit coupled between the transformer and the CCFL circuit. The CCFL circuit includes multiple CCFL loads. The transformer includes a primary winding and a secondary winding, with the primary winding coupled to a voltage source and the secondary winding coupled to the CCFL loads. The controlling circuit includes a part for generating a predetermined voltage signal to power the CCFL loads during a warm-up stage and another part for generating a modulation signal. With such circuit arrangement, each of the multiple CCFL loads is powered from an off state to an operationally-on state.

Abstract: A discharge lamp lighting circuit includes an open protection circuit. The discharge lamp lighting circuit includes an open protection circuit and an over-voltage detecting circuit. The open protection circuit detects whether any of the discharge lamps are unlit, and sends a voltage control signal to a control circuit if one of the discharge lamps is not lit, whereby the control circuit sends a pulse signal to a buck converter according to the voltage control signal, and the buck converter generates and outputs a DC voltage according to the pulse signal. If the DC voltage from the buck converter reaches a predetermined voltage, the over-voltage detecting circuit conducts and sends a voltage control signal to the control circuit, and the control circuit ceases operating according to the voltage control signal. Consequently, damage to the other normal discharge lamps is prevented.

Abstract: A starting voltage adjustment circuit (70), which can vary starting voltages to CCFLs (40) according to variations in the temperature of the immediate environment, is employed in an apparatus for driving CCFLs. The starting voltage adjustment circuit includes a zener diode (710), a thermal resistor (720), and a voltage dividing resistor (730) connected in series between a buck converter, a resonant boost converter, and ground. The starting voltage adjustment circuit also includes a control chip (740) which includes pins, of which one is connected between the thermal resistor and the voltage dividing resistor and outputs a constant voltage, and another is connected between the voltage dividing resistor and ground. The thermal resistor has a voltage drop thereacross varying with the temperature. The starting voltage adjustment circuit adjusts an input voltage to the resonant boost converter, thereby adjusting the starting voltage to the CCFLs according to variations in temperature.

Abstract: A discharge lamp lighting circuit includes an open protection circuit. The discharge lamp lighting circuit includes an open protection circuit and an over-voltage detecting circuit. The open protection circuit detects whether any of the discharge lamps are unlit, and sends a voltage control signal to a control circuit if one of the discharge lamps is not lit, whereby the control circuit sends a pulse signal to a buck converter according to the voltage control signal, and the buck converter generates and outputs a DC voltage according to the pulse signal. If the DC voltage from the buck converter reaches a predetermined voltage, the over-voltage detecting circuit conducts and sends a voltage control signal to the control circuit, and the control circuit ceases operating according to the voltage control signal. Consequently, damage to the other normal discharge lamps is prevented.

Abstract: A starting voltage adjustment circuit (70), which can vary starting voltages to CCFLs (40) according to variations in the temperature of the immediate environment, is employed in an apparatus for driving CCFLs. The starting voltage adjustment circuit includes a zener diode (710), a thermal resistor (720), and a voltage dividing resistor (730) connected in series between a buck converter, a resonant boost converter, and ground. The starting voltage adjustment circuit also includes a control chip (740) which includes pins, of which one is connected between the thermal resistor and the voltage dividing resistor and outputs a constant voltage, and another is connected between the voltage dividing resistor and ground. The thermal resistor has a voltage drop thereacross varying with the temperature. The starting voltage adjustment circuit adjusts an input voltage to the resonant boost converter, thereby adjusting the starting voltage to the CCFLs according to variations in temperature.

Abstract: A CCFL (cold-cathode fluorescent lamp) driving system for multiple CCFL loads includes a transformer, a CCFL circuit, and a controlling circuit coupled between the transformer and the CCFL circuit. The CCFL circuit includes multiple CCFL loads. The transformer includes a primary winding and a secondary winding, with the primary winding coupled to a voltage source and the secondary winding coupled to the CCFL loads. The controlling circuit includes a part for generating a predetermined voltage signal to power the CCFL loads during a warm-up stage and another part for generating a modulation signal. With such circuit arrangement, each of the multiple CCFL loads is powered from an off state to an operationally-on state.