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What is a field effect tube?

Field effect is an effect of long-distance polarity that can interact with each other, transmitting electron effects through spatial and solvent molecules. It can generate an electric 

field within space through intramolecular electrostatic forces in space, affecting reaction centers at another location. The field-effect transistor is a semiconductor device that uses 

such an electric field effect to control its current size. Its advantages include small size, light weight, low power consumption, simple packaging, few pins, and long lifespan. It has 

many advantages, including high input impedance, low noise stability, strong radiation resistance, and more. Due to its very simple manufacturing process, the field-effect transistor 

is highly economical and practical. Because of its wide range of applications, it can even withstand operation at 0-degree coefficient, making it widely used.

The working principle of the field effect tube

The field-effect transistor is a current-controlled element. It is also called a bipolar device because it can operate with both majority and minority carriers.

Classification of FET

Insulated gate field effect transistor

Insulated gate field effect transistor (Metal Oxide_Semiconductor FET), abbreviated as MOSFET

There are many kinds of insulated gate field effect transistors, such as PMOS, NMOS and VMOS power transistors, but MOS transistors are used most.

(Metal oxide semiconductor field effect transistor)

The schematic diagram and symbols of the structure of an N-channel enhanced MOSFET. It is formed on a P-type silicon substrate by diffusing two high-concentration N regions, 

creating a thin layer of silicon dioxide (SiO2) insulating layer between the two N regions, and then drawing three electrodes—referred to as source s, gate g, and drain d—on the SiO2 

and the two N regions. In its schematic symbol, the arrow indicates the actual direction of the drain current.

assumption diagram：

The conduction mechanism of an Insulated Gate Field Effect Transistor (IGFT) is to control the width of the conductive channel by adjusting the amount of "induced charge" using UGS, 

thereby controlling the drain current ID. When UGS=0, there is no conductive channel between the source and drain, which is referred to as an enhancement MOSFET. When UGS=0, 

there is a conductive channel between the drain and source, which is referred to as a depletion MOSFET

The main parameters of the field effect tube

(1) On voltage UT (U is the parameter of MOS enhancement tube, the gate source voltage is less than the absolute value of the on voltage, the field effect tube cannot conduct)

(2) Break voltage Up Up is the parameter of MOs depletion and junction FET. When ucs = Up, the drain current is zero.

(3) Saturation drain current IDss MOS depletion and junction FET, the drain current corresponding to when ucs = 0.

(4) Input resistance Rcs Junction field-effect transistor, Re greater than 1079, MOS field-effect transistor, R can reach 10~10152.

(5) Low frequency transconductance gm gm reflects the control effect of gate voltage on drain current, with units of mS (milli Siemens). 

(6) The maximum drain power consumption PoM PDw= UDs Lp is comparable to that of the bipolar transistor.

Application of field effect tube

The application of field effect is very extensive, mainly in the following aspects. Signal amplification switch, control, voltage controller, analog switch, motor drive and control, industrial 

control equipment, sensor, interface circuit, automotive electronics, green lighting.

Common brands of field effect tubes

1、(Infineon): Infineon is a global leading semiconductor technology company focusing on the production of IGBT components discrete devices smart card chips and power semiconductor products etc. The company provides semiconductor and system solutions for automotive and industrial power devices chip cards and security applications etc.

2、(Texas Instruments, TI): Texas Instruments is a globally renowned semiconductor company known for the development, manufacture, and sale of semiconductor and computer technologies. Its products are widely used in markets such as industry, automotive, personal electronics, communication equipment, and enterprise systems‌2.

3、(onsemi): ON Semiconductor has become the world's leading semiconductor manufacturer since its spin-off from Motorola in 1999, offering more than 80,000 different devices and a global supply chain.

4、(STMicroelectronics): STMicroelectronics was formed by the merger of SGS Microelectronics and Thomson Semiconductor, Italy and France, and has performed well in the market of integrated multimedia applications and power solutions.

5、(Toshiba): Toshiba is a well-known brand in Japan, providing integrated electromechanical manufacturers and solutions, and is a large integrated electronics and electrical enterprise group 1.

6、(RENESAS) Renesas is a world-renowned semiconductor chip supplier, formed by the merger of NEC Electronics, Hitachi Manufacturing Semiconductor Division and Mitsubishi Electric Semiconductor Division.

7、(VISHAY) VISHAY is the world's largest manufacturer of discrete semiconductor and passive electronic components, founded in 1962 in the United States.