The role and characteristics of field effect tube

The main role of the FET

1. FETs can be used for magnification. Since the input impedance of the FET amplifier is high, the coupling capacitor can be small, and the electrolytic capacitor is not necessary.

2. The high input impedance of the FET is very suitable for impedance transformation. It is often used in the input stage of multi-stage amplifier for impedance transformation.

3. FETs can be used as variable resistors.

4. The FET can be conveniently used as a constant current source.

5. FETs can be used as electronic switches.

It features

(1) FET is a voltage control device, which controls ID through VGS;

(2) The input current of the FET is extremely small, so its input resistance is very large.

(3) It uses majority carriers for conduction, so its temperature stability is better;

(4) The voltage amplification factor of the amplifier circuit formed by it is smaller than the voltage amplification factor of the amplifier circuit formed by the triode;

(5) The FET has strong radiation resistance;

(6) The noise is low because there is no shot noise caused by minority carrier diffusion of chaotic motion.

Model name

There are two naming methods.

The first naming method is the same as that of bipolar transistors, the third letter J stands for junction field effect transistor, and O stands for insulated gate field effect transistor. The second letter represents the material, D is P-type silicon, the inversion layer is N-channel; C is N-type silicon P-channel. For example, 3DJ6D is a junction P-channel FET, and 3DO6C is an insulated gate N-channel FET.

The second naming method is CS××#, CS stands for FET, XX stands for the serial number of the model with numbers, and # stands for different specifications in the same model with letters. For example CS14A, CS45G, etc.

Shenzhen Quanyouxing Technology Industrial Co., Ltd. was established in 2012 as a general taxpayer enterprise.

Our company is a professional sales agent: PANJIT Qiangmao (diode), MAPLESEMI (MOSFET), Limai Semiconductor (power triode, diode), Suzhou Huaxin ( HS, power management IC), Nanjing Micro Alliance (MICRONE), Nanhai Saiwei (SIFIRST), Jinan Guxun Electronic Devices Co., Ltd. (JGD), Jilin Huawei, Fuman Electronics and other diodes, bridge rectifiers, triodes, field effect MOSFET (MOSFET), power management IC company. The company is committed to the promotion and sales of semiconductors in the power supply industry. Customers are distributed in: UPS, INVERTER (inverter), chassis power supply, 80+ energy efficiency power supply, electrical appliances, car chargers, adapters, AV, TV POWER, LED power supplies, etc.