Adjust the incandescent light
We know that Through the silicon controlled rectifier(SCF)can adjust the incandescent light and shade degree.but there are has some question is values for our design work.
*In order achieve this goal, check the phase angle of input power is necessary ,we can confirm that conducting time of SCF when the Zero crossing circuit is check out. But that’s quite difficult to do in practice, Because the noise interference will trigger conducting status is poor .error trigger to generate the current oscillation.
* Whole AC voltage almost load into LC filter of LED power on SCF conducting state. At moment , if adjust current is low that SCF maintain current ,the SCF stopped conducting.
* From datasheet, The maintain current of SCF between 8mA ~ 75mA.the incandescent work current is far more than maintain currnet,the work current will support SCF.