The role of the transistor characteristic code, what is

Function: Amplification of electric current.

Characteristics: A small change in the base emitter current can cause a large change in the pole emitter current.

Codename: V (or V3).

In foreign countries, it is generally represented by Yumu QR or Q, and in China, it is generally represented by VT or V.

Transistor. English: triode) is a vacuum tube with amplifier function, with three electrodes inside a glass housing of a vacuum:

It consists of a heated filament (or cathode), control grid, and metal plate (anode). The transistor was invented by Lee DeForrest in 1906 and was the first electronic amplifier.

It is also the ancestor of other types of vacuum tubes such as quadriodes and pentodes. Its invention ushered in the electronic age, making radio amplification and long-distance ** possible.

Lee DeForrest is known as the father of electronics for his invention of the transistor. Today's transistors are only about one centimeter long. Transistors have been widely used in consumer electronic devices such as radios.

and televisions. Until the 70s of the last century were replaced by transistors. Currently, tubes.

It is mainly used for high-power RF power amplifier tremor in radio transmitters and industrial RF heating devices.

All transistors have a hot cathode electrode that is heated by a filament and releases electrons, and a flat metal plate electrode that attracts electrons, and between them there is a grid of wire mesh that controls the current. They are sealed in a glass container from which air has been pumped to a high vacuum of approximately 10 -9 atm.

Since the filament eventually burns out, the eggplant tube therefore has a limited lifespan and is made into replaceable units; The electrode brigade is connected to the terminal that is plugged into the socket.

Pin on. The service life of a triode is about 2000 hours for a small tube and 10000 hours for a power tube.

Apply. The transistor was the first non-mechanical device to provide power gain in audio and RF.

as well as practical by radio. Transistors are used in amplifiers and oscillators. Many types are only used at low to medium frequencies and power levels.

The large water-cooled transistor can be used as the final amplifier of the radio transmitter with a power rating.

for kilowatts. Special types of transistors ("lighthouse" tubes, with low capacitance between elements) provide useful gain at microwave frequencies.

Vacuum tubes are sold in consumer electronics by the masses.

has become obsolete and has been replaced by cheaper transistor-based solid-state devices. Recently, however, vacuum tubes have made a comeback. Transistors continue to be used in certain high-power RF amplifiers and transmitters.

While proponents of vacuum tubes claim their advantages in areas such as high-end and professional audio applications, solid-state MOSFETs have similar performance characteristics.

Characteristics of the transistor:

1. The launch zone emits electrons to the base zone.

The power supply UB is added to the emission junction through the resistor RB, and the emission junction is positively biased, and most of the carriers (free electrons) in the emission region continuously cross the emission junction into the base region, forming the emitter current IE. At the same time, most of the carriers in the base region also diffuse to the emission region, but since the concentration of most carriers is much lower than the concentration of carriers in the emission region, this current can be disregarded, so it can be considered that the emission junction is mainly an electron flow.

2. Diffusion and recombination of electrons in the base region.

After the electrons enter the base region, they are first densely packed near the emission junction, and gradually form an electron concentration difference, which promotes the electron flow to diffuse to the collector junction in the base region, and is pulled into the collector region by the collector electric field to form a collector current IC. There is also a small fraction of electrons (because the base region is very thin) that reunites with the holes in the base region, and the ratio of the diffusion electron flow to the composite electron flow determines the amplification ability of the triode.

3. Collect electrons in the collector area.

Due to the large external reverse voltage of the collector junction, the electric field force generated by this reverse voltage will prevent the electrons in the collector region from spreading to the base region, and at the same time pull the electrons that diffuse to the vicinity of the collector junction into the collector region to form the collector main current ICN.

In addition, a small number of carriers (holes) in the collector region will also produce drift motion, and the reverse saturation current will flow to the base region, which is represented by ICBO, and its value is small, but it is extremely sensitive to temperature.