ALTERNATING CURRENT PULSE WIDTH MODULATION DIMMING CIRCUIT

摘要

PURPOSE: An AC PWM(Pulse Width Modulation) dimming circuit is provided to control the dimming of a lamp by controlling the voltage of the AC input power through a PWM. CONSTITUTION: A drain of a first semiconductor switch(330) is connected to an AC input power(310). A source of the first semiconductor switch is connected to the source of a second semiconductor switch(340). A gate of the first semiconductor switch is connected to a PWM signal input unit(360). The drain of the second semiconductor switch is connected to a lamp(350). The source of the second semiconductor switch is connected to the source of the first semiconductor switch. The gate of the second semiconductor switch is connected to the PWM signal input unit. A high frequency filter(320) is connected in parallel to the AC input power to rectify the switching current.