Field effect transistor (Field Effect Transistor abbreviation (FET)) referred to as field effect transistor. The general transistor is composed of two kinds of polar carriers, that is, the majority carrier and the reverse polarity of the minority carriers involved in conduction, so called bipolar transistors, and FETs only by the majority of carriers involved in conduction , Which is the opposite of bipolar type, also known as unipolar transistor. It is a voltage-controlled semiconductor device with the advantages of high input resistance (108 ~ 109Ω), low noise, low power consumption, large dynamic range, easy integration, no secondary breakdown, safe working area and so on. Very powerful competitors for transistor and power transistors.
First, the classification of field effects

 

Field effect tube split type, insulated grid type two categories. JFETs are named after two PN junctions, and the insulated gate-type FET (JGFET) is named for the complete isolation of the gate and other electrodes. In the insulated gate type FET, the most widely used MOS field effect transistor, referred to as mos tube (ie metal - oxide - semiconductor field effect transistor MOSFET); in addition to PMOS, NMOS and VMOS power FET, As well as the recently introduced πMOS field effect transistor, VMOS power module.

According to the different channels of semiconductor materials, the junction and the insulation gate of the sub-channel and P-channel two. If the way by the way to divide, FET can be divided into depletion and enhanced. Junction field effect tubes are depleted, insulated gate type FETs both depleted and enhanced.

Field effect transistors can be divided into junction field effect transistors and MOS field effect transistors. And MOS field effect transistor is divided into N ditch depletion type and enhanced type; P ditch depletion type and enhanced four categories.

Second, the field effect transistor model naming method

There are two naming methods.

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

The second naming method is CS × × #, CS on behalf of the FET, × × number to represent the serial number, # with the letter on behalf of the same model in the different specifications. Such as CS14A, CS45G and so on.

Third, the field effect of the parameters

Many parameters of the FET, including DC parameters, AC parameters and limit parameters, but the general use of the following main parameters:

1, I DSS - saturated drain current. Refers to the junction current or depletion type insulated gate FET, the gate voltage U GS = 0 when the drain current.

2, UP

Working in the switch state of the transistor can be called switch tube. Transistor has PNP, NPN, single junction transistor and so on.