Patent ID: 11895749
Assignee: JOULWATT TECHNOLOGY CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 13:
14. The LED drive circuit according to claim 13, wherein when the input AC power supply is front-cut by the dimmer, the comparing unit comprises:
a first comparing circuit, wherein a positive input terminal of the first comparing circuit receives a first reference voltage signal, and a negative input terminal of the first comparing circuit receives the sampling signal;
a second comparing circuit, wherein a positive input terminal of the second comparing circuit receives a second reference voltage signal, and a negative input terminal of the second comparing circuit receives the sampling signal;
a first RS flip-flop, wherein a set terminal of the first RS flip-flop is connected to an output terminal of the first comparing circuit, a reset terminal of the first RS flip-flop is connected to an output terminal of the second comparing circuit, and an output terminal of the first RS flip-flop outputs a time signal; and
a first time comparing unit, wherein a first input terminal of the first time comparing unit is connected to the output terminal of the first RS flip-flop, a second input terminal of the first time comparing unit receives a reference time signal, and an output terminal of the first time comparing unit outputs the regulating signal.