Field Effect Transistor

In the Bipolar Junction Transistor, we study that it is a current controlled device that means the output Collector current of the transistor is proportional to the input current flowing into the Base terminal of the device.

Field Effect Transistor (FET) uses the voltage that is applied to their input terminal, called the Gate to control the current flowing through them resulting in the output current being proportional to the input voltage. As their operation depends upon on an electric field (hence the name field effect) generated by the input Gate voltage, this then makes the Field Effect Transistor a “voltage controlled device”.

 Field Effect Transistor is a three-terminal unipolar semiconductor device that has very similar characteristics to those of their bipolar junction transistor. As an example, high efficiency, instant operation, robust and cheap and it can be used in most electronic circuit applications in place of bipolar junction transistors (BJT).

It can be designed much smaller than an equivalent BJT transistor with their low power consumption and power dissipation makes them ideal for use in integrated circuits.

There are two main classifications of field effect transistor, the Junction Field Effect Transistor (JFET) and the Insulated-gate Field Effect Transistor ( IGFET), which is also known as the standard Metal Oxide Semiconductor Field Effect Transistor (MOSFET).