Voltage Controlled Resistor Mosfet

Two types of fets are often used.

Voltage controlled resistor mosfet. The resistor will only produce 4v drop if the current through the resistor will 400ma 4a. In the source supply and apply the control voltage between the power supply side of the resistor and the gate this will stabilise the current through the mosfet to some extent. Most commonly the resistance rds from drain to source is modulated by the gate voltage vgs. It won t be very easy to tune it to behave like a proper resistor.

In the ohmic region1 the drain to source current i. The ohms law is applied in this scenario. Technically the mosfet can operate as a variable resistor but there are two main issues. These resistors in turn may be used as the control element in more complicated electronic circuits.

A voltage controlled resistor vcr is a three terminal active device with one input port and two output ports. The field effect transistor as a voltage controlled resistor we consider the use of a n channel fet as a voltage controlled resistor where the resistance between the drain and source is controlled by the gate source voltage. The answer is yes e g vcr11 but it turns out that virtually any other fet e g jfet and mosfet can be used as a voltage controlled resistor. A voltage controlled resistor vcr may be defined as a three terminal variable resistor where the resistance val ue between two of the terminals is controlled by a voltage potential applied to the third.

This is because voltage current x resistance. To prevent the resistance from ever going too low you could put a low valve high power resistor in series. The output of the op amp turn on and control the mosfet until the voltage drop across the shunt resistor became 4v. The jfet and the mosfet.

The mosfet is a three terminal device. Basic voltage controlled resistor vcr circuits one of the simplest uses of a voltage controlled resistor is an electronically controlled attenuator or volume control. The input port voltage controls the value of the resistor between the output ports. Mosfet is a voltage controlled field effect transistor that differs from a jfet.

There are two distinct regions. In the ohmic region which is quite narrow in terms of output voltage the linearity is poor and it also depends on input voltage. The gate electrode is electrically insulated from the main semiconductor by a thin layer of insulating material glass seriously.