Patent ID: 8111016

Claim:
A control system for multiple fluorescent lamps, comprising: a first ramp waveform generator configured to generate a first ramp waveform signal; a first comparator configured to compare the first ramp waveform signal against a first reference voltage different from a ground potential, and to output a result signal that has a first voltage level when the first ramp waveform signal is higher than the first reference voltage and a second voltage level when the first ramp waveform signal is lower than the first reference voltage; a one-shot generator configured to output a one-shot pulse according to the result signal outputted from the first comparator; a second ramp waveform generator configured to generate a second ramp waveform signal in response to the one-shot pulse; and a second comparator configured to output a phase delayed signal according to a result of comparison between the second ramp waveform signal and a second reference voltage.