| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable a light emitting diode to be lit, with phase-controlled voltage, such that light intensity is adjustable like a bulb. <P>SOLUTION: The output voltage of a phase control circuit 12 is fed to a DC power supply 15 and an striking phase detecting circuit 16. The DC power supply 15 smoothes the voltage that is phase-controlled by the phase control circuit 12 to obtain DC power having constant voltage, and the output of the DC power supply is fed to a switching circuit 17. Meanwhile, the striking phase detecting circuit 16 detects the striking phase of the voltage that is phase-controlled by the phase control circuit 12 to output the detection result to a control operation portion 18 to change the output of the switching circuit 17. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
