Crystal triode:
The transistor transistor is one of the basic components of semiconductors. It has the function of current amplification and is the core component of electronic circuit. A triode is made of two PN junctions extremely close to each other on a semiconductor substrate. The two PN junctions divide the bulk semiconductor into three parts. The middle part is the base region, and the two sides are the emitter region and collector region, which are arranged as PNP and NPN. Its classification 1, according to the material: silicon tube, germanium tube. Here we have APEM-A029407.
2, according to the structure: NPN, PNP.
3, according to function: switch tube, power tube, Darlington tube, photosensitive tube and so on.
4, according to power: tiny power tube, medium power tube, high power tube.
5, according to the working frequency: low frequency tube, peak frequency tube, overclocking tube.
6, according to the structure of the process: alloy tube, flat tube.
7, according to the installation mode: plug-in transistor, patch transistor.
Today I will introduce the power tube commonly used in household appliances, field effect tube (FET): Effect transistor (FET). The conductor involves most conduction, also known as a monopole transistor. It belongs to voltage controlled semiconductor devices. It has elevated input resistance (108~109Ω), low noise, low power consumption, large dynamic range, easy integration, no secondary breakdown, wide safe working area and so on. It has become a powerful bipolar transistor and power transistor. It is commonly used in circuit diagrams.
In a word, the working principle of FET is "the ID of the channel flowing between the drain-source terminal, and the reverse biased gate voltage control ID formed by the pn junction between the gate and the channel". More properly, the width of the channel through which ID flows, i.e., the channel cross-sectional area, is controlled by the shift of pn junction inversion, resulting in the shift of depletion layer spread. In the unsaturated region of VGS=0, the expansion of the transition layer represented is not large. According to the electric field of VDS applied between the drain and the source, some electrons in the source region are pulled away by the drain, that is, there is a current ID flowing from the drain to the source. The excess layer extending from the gate to the drain constitutes a part of the channel as a blocked type with ID saturation. This state is called clipping. This means that the transition layer is blocking part of the channel, rather than cutting off the current.