Patent ID: 7180247

Claim:
A load control circuit connected to a first capacitor, a second capacitor, a first load, and a second load, the load control circuit comprising: a first triangular wave generation circuit, connected to the first capacitor, for generating a first triangular wave signal by charging and discharging the first capacitor; a second triangular wave generation circuit, connected to the second capacitor, for generating a second triangular wave signal by charging and discharging the second capacitor, the second triangular wave signal having an amplitude that is the same as that of the first triangular wave signal; a potential converter for generating a reference potential; a first waveform shaping circuit, connected to the potential converter and the first triangular wave generation circuit, for converting the first triangular wave signal based on the reference potential to a first duty signal to control the first load; and a second waveform shaping circuit, connected to the potential converter and the second triangular wave generation circuit, for converting the second triangular wave signal based on the reference potential to a second duty signal to control the second load, the first triangular wave generation circuit changing at least one of a time constant for charging the first capacitor and a time constant for discharging the first capacitor so that the first duty signal changes differently from the second duty signal.