Voltage dividing self-bias circuit

Voltage dividing self-bias circuit

The figure above shows a voltage-dividing self-bias circuit, also known as a gate-connected positive potential bias circuit. It is based on a self-biased common-source amplification circuit and is composed of voltage-dividing resistors R and R. In the figure, the power supply UDD, input coupling capacitor cl, output coupling capacitor C2, drain resistor R, source resistor Rs, source bypass capacitor C; all have the same function as the self-biased common source amplifier circuit. Rti and R丶 are voltage-dividing bias resistors, and the contact point between Rn and R is connected to the gate through a large resistor Rf. Since there is no current in the gate insulation, the voltage dividing point A of Rn and R is at the same potential as the gate. Since this circuit has both "voltage division bias" and "self-supply bias", it is also called a group bias circuit. This bias circuit can be used for depletion mode field effect transistors or enhancement mode field effect transistors.