I am going to talk about the basic operation MOSFET.

MOSFET stands for metal oxide semiconductor field-effect  transistor. Like any conventional transistor, it is a type of transistor  with many applications in modern power electronics. Moreover, its  functioning is based on how electricity flows through it. It is  important to note that there are many variations in the uses of the  MOSFET in different circuits. In MOSFET, the voltage  applied to the gate region determines how much current flows from drain  to source. And, this property gives MOSFETs their name – Metal Oxide  Semiconductor Field Effect Transistors. Interestingly, these transistors  can amplify a signal or let only one specific kind of electric charge  carrier through.

There are three basic types of MOSFETs. 

The first type is the “N-channel enhancement-mode MOSFETs” or  usually on (n-channel MOSFET). It allows current flow through the  channel between drain and source even with zero input voltage applied  across its terminals. Also, this means that it needs no gate signal for  operation and hence is helpful in simple digital circuits.

The second type of MOSFETs are the “N-channel depletion-mode”  or usually off (n-channel). This type requires a negative voltage for it  to turn on and allow the flow of electric currents. Also, it has an  advantage since this type of transistor acts as a resistor when it is  off. Hence, very useful in specific applications that require control of  input voltage.

Thirdly, the “P-channel depletion-mode MOSFET transistor” is  usually off (p-channel MOSFET). This type blocks any current to flow  through it unless a positive charge flows across its terminals. It means  that this type of transistor acts as an insulator. Therefore, it is not  suitable in specific applications where it is necessary to pass current  at all times.

What is a MOSFET? How MOSFETs Work? (MOSFET Tutorial) – YouTube 

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