Classification, parameters and functions of FETs

Classification, parameters and functions of FETs

A field-effect transistor is a semiconductor component that uses carriers to achieve conduction, and the output current of the electron tube is adjusted according to the magnetic effect of the current by applying the input voltage, also known as A field-effect transistor.

Classification of FETs

FETs are available in junction type and insulated gate type. The knot type is mainly that there are 2 PNs. The insulating gate type is mainly insulating from the gate, and at present, MOS field effect tubes (classified as insulating gate types) are used more.

The basic parameters of the field effect tube

, saturated drain-source current.

, clamp off voltage.

, turn on the voltage.

, transconductance.

, drain-source breakdown voltage.

, dissipated power.

, drain-source current.

The role of FETs A field-effect transistor

, FET amplification, the capacity of the coupling capacitor is small, and the input impedance of the amplifier is high.

, the impedance transformation effect of FETs on amplifiers.

FETs can actually be used for variable resistors.

The FET can be easily used for constant current sources.

FETs can be used for electronic switching.

FET vs. transistor

(1) FETs and transistors according to the relationship between current and voltage can be known, for the signal source, the current is less, then the FET is more suitable, if the voltage is lower and the current is more, the transistor is more suitable.

(2) FETs are unipolar components, and unipolar elements are bipolar components. FETs conduct electricity using majority carriers, and transistors conduct electricity using majority and minority carriers.

(3) FETs are more flexible than transistors.

(4) The current and voltage that FETs rely on can be very low.