This kit controls the brightness of dc light bulb or the speed of small dc motor by PWM (pulse-width-modulation). A two-transistor astable circuit generates a square wave with fixed frequency & varying duty cycle. The duty cycle can be changed by adjusting the potentiometer (VR) . The duty cycle of the square wave determines load power. A Power MOSFET is used to drive the load.
Applications : DC motor speed control or light bulb brightness control
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