| 摘要 |
PURPOSE:To enable a desired flickering operation by detecting a state that one level period of a flickering control signal is equal to or smaller than one operation period of an illumination load in a lighting control part and next prolonging said one level period to be in excess of said one operation period. CONSTITUTION:An output of a monostable multivibrator 10 is raised to output a pulse at a time t11 when an output of a flickering control part 7 is raised. The output of the monostable multivibrator 10 is lowered at a time t12 behind a period W2 after the time t11, and high levels of outputs of this monostable multivibrator 10 and this flickering control part 7 are selected and outputted in a logic sum circuit 11. A light regulation signal is thus obtained to have a rising period W3 equal to a rising period W1. Even if the rising period W1 is smaller than the sampling period W2, the outputs of the flickering control part 7 and the monostable multivibrator 10 are outputted through the logic sum circuit 11. A light regulation signal with the rising period W3 equal to or larger than the rising period W1 at the flickering control part 7 can be obtained accordingly. |
