Patent attributes
A silicon-controlled rectifier (SCR) dimming circuit and a dimming control method are disclosed. The SCR dimming circuit includes a SCR element, a rectifier circuit, a filter circuit, a power converter, and a dimming control circuit. The dimmer control circuit includes a phase angle detection circuit, an output current feedback control circuit, an input current control circuit, a maximum operation time detection circuit, and a logic operator. An input current sampling signal fluctuates near a predetermined value after the SCR element is turned off by turning on and off the power converter, so that the input AC current is less than a holding current of the SCR element. The present SCR dimming circuit and the present dimming control method can avoid repeatedly turning on the SCR element in cycles of an operating frequency. Thus, the linearity of dimming is improved and the flicker of an LED lamp is eliminated.
