Stepless dimmer using V-MOS field effect tube

The resistor R and the potentiometer RP form a voltage divider. Adjusting the resistance of the potentiometer RP can change the bias
voltage of the gate of the V-MOS tube. Since the V-MOS tube is a voltage control device, its gate bias determines its value. The voltage between drain and source. When
the resistance value of the potentiometer RP is adjusted small, the gate bias voltage of vr decreases, the drain and source voltage drops of VT increase, the voltage at both ends of the bulb H
decreases, and the luminous brightness weakens: when the resistance value of the potentiometer R adjusts When the voltage is large, the VT gate bias increases, the drain and source voltage drops of VT
decrease, the voltage across the bulb increases, and the luminous brightness increases accordingly. Therefore, adjust the potentiometer
RP to adjust the brightness of the bulb H as desired .