Patent ID: 8139378

Claim:
A LED dimmer device for use in a dimmer, comprising: a rectifier adapted for transforming alternating current into direct current; a voltage boost device including a metal oxide semiconductor field effect transistor used to make the dimmer entering into a normal edge state; a pre-voltage detection circuit and an after-voltage detection circuit adapted for detecting voltages; a master chip adapted for driving the circuits and elements to work, the master chip including an integrated comparisor used to compare the voltages; an elementary transformer and a secondary transformer adapter for changing the voltages; a secondary rectifier adapted for rectifying and a secondary filter capacitance circuit adapter for filtering; and a secondary switch tube used for driving the elementary transformer and the secondary transformer, the secondary rectifier, and the secondary filter capacitance circuit so as to drive an LED power supply to illuminate; wherein the voltage booster device is adapted for enabling on-time current and on-time voltage of the dimmer being in the same phase mode and having a relative lower peak value of current, and wherein when the alternating current is rectified, the voltages of the pre-voltage detection circuit and the after voltage detection circuit are simultaneously inputted into the integrated comparisor of the master chip, which control a frequency and a duty-cycle of the voltage boost device to insure that a difference between the step-up voltage and voltage elementary rectified is maintained at 30 volt.