MOSFETs are in all aspects, Very Very similar to a transistor. But a MOSFET is a voltage controlled semiconductor.
An FET is called a Field Effect Transistor where an electric field controls a silicon wafer inside the package... kinda like a current isolator.
In a sense the name itself explains its operation, transistor controlled by an electrical field.
MOSFET is a form of a Field Effect Transistor. MOSFET stands for Metal Oxide Semiconductor-Field Effect Transistor.
MOSFETs are like a Tri-layer PNN Junction Diode or NPP Junction Diode, where the middle layer is Doped with elements like boron oxide or titanium(II) trioxide. A silicon wafer at the side doped with arsenic or boron to control the PNN or NPP Junctions.
FETs and MOSFETs are most useful for Bilateral switching and amplifying. You could also say they are solid state vacuum tubes too since they have a high tolerance for high current and high voltage.
CMOS is a Variation of a FET used in computers to save energy since current consumption is extensively less. CMOS is the complementary version of transistor TTL logic.
When Voltage is Applied to the Gate of an FET the transistor will switch. Most switching occurs on the gate with a voltage threshold of 0.4 volts.
Cheat Sheet
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