The hard and meaningful internship life is over again. Looking back on the internship experience during this period, we have gained not only years, but also growth. The most critical step at this time is to write an internship summary. What kind of internship summary should you have seen? The following is a summary of my internship in electronic technology, for reference only. Welcome to reading.

First, the internship time

Xx, xx, xx, xx, XX, Week 19

Second, the internship location

Electronic technology training room (1)

Third, the purpose of the internship

1. Through the installation, welding and debugging of HX203FM/AM integrated circuit telephone in this project design, students can understand the assembly process of electronic products;

3. Learn the assembly process of the whole machine; Cultivate hands-on ability and rigorous work style.

2. Master the identification and quality inspection of electronic components;

Fourth, the internship content

1, printed circuit board

Printed circuit board (PCB) will appear in almost every kind of electronic equipment. If there are electronic parts in a device, they are all embedded in PCB of different sizes. In addition to fixing various small parts, PCB is mainly used to provide electrical connection between the above parts. With the increasing complexity of electronic equipment, more and more parts are needed, and the lines and parts on PCB are more and more dense.

There are no parts on a standard PCB, which is usually called "Printed Circuit Board (PWB)".

The substrate of the board itself is made of insulating and heat-insulating materials that are not easy to bend. The fine wiring material visible on the surface is copper foil. Originally, the whole board was covered with copper foil, but a part of it was etched away in the manufacturing process, and the rest became fine wiring in a mesh. These wires, called conductor patterns or wiring, are used to provide circuit connections for components on the PCB.

In order to fix the parts on the PCB, we weld their pins directly on the wiring. On the most basic PCB (single board), the parts are concentrated on one side and the wires are concentrated on the other side. In this way, we need to make holes in the board so that the pins can pass through the board to the other side, so the pins of the parts are welded to the other side. Because of this, the front and back of PCB are called component surface and soldering surface respectively.

If there are some parts on the PCB that need to be removed or put back after production, sockets will be used when installing the parts. Because the socket is directly welded on the board, the parts can be disassembled at will.

If we want to connect two PCB boards to each other, we usually use the edge connector commonly known as "Golden Finger". Gold finger contains many exposed copper pads, which are actually part of PCB wiring. Usually, when connecting, we insert the gold finger on one PCB into the corresponding slot (commonly known as expansion slot) on another PCB. In computers, such as graphics cards, sound cards or other similar interface cards, they are all connected to the motherboard through gold fingers.

Green or brown on PCB is the color of solder mask. This layer is an insulating protective layer, which can protect the copper wire and prevent the parts from being welded to incorrect places. In addition, a screen will be printed on the solder mask. Usually words and symbols (mostly white) are printed on it, indicating the position of each part on the chessboard. Screen printing surface is also called legend.

Printed circuit board (PCB) is an indispensable basic component of all electronic products, which is carefully and neatly planned, etching complex circuit copper wires between parts on a board, providing the main support for the installation and interconnection of electronic components.

Printed circuit boards are flat plates made of non-conductive materials, which are usually designed with pre-drilled holes for mounting chips and other electronic components. The holes of the components help to connect the predetermined metal paths printed on the circuit board. After the pins of the electronic component pass through the PCB, the conductive metal covered electrode is adhered to the PCB to form a circuit.

Step 2 resist

Elements with a certain resistance are made of conductors.

Resistance is the basic property of conductor, which is related to the size, material and temperature of conductor.

Function: The main function is to prevent the current from flowing, and it is applied to current limiting, shunt, step-down, voltage division, load and capacitor matching as filter and resistor matching.

First, according to the resistance characteristics: fixed resistance, adjustable resistance and special resistance (sensitive resistance).

What cannot be adjusted is called constant resistance, and what can be adjusted is called adjustable resistance. Common ones, such as radio volume adjustment, are mainly used for voltage distribution, which we call potentiometers.

According to the manufacturing materials: carbon film resistance, metal film resistance, wire wound resistance, etc.

Iii according to the installation method: plug resistance, patch electricity.

The main parameters of the resistor: resistance value, accuracy, temperature coefficient (temperature drift TCR) and package size.

3. Potentiometer

Potentiometer is an adjustable electronic component. It consists of a resistor and a rotating or sliding system. When a voltage is applied between two fixed shocks of the resistor, the position of the contact on the resistor is changed by rotating or sliding the system, and a voltage related to the position of the moving contact can be obtained between the moving contact and the fixed contact. It is mostly used as a voltage divider, which is a potentiometer and a four-terminal element. Potentiometer is basically a sliding rheostat, there are several styles, which are generally used to adjust the volume switch of the speaker and the power of the laser head.

4. Capacitance

Capacitor is an electronic component, which consists of two conductors (cathode and anode) sandwiched between an insulator (medium). The types of capacitors should first be classified according to the types of media. These can be divided into three categories: inorganic dielectric capacitors, organic dielectric capacitors and electrolytic capacitors. Capacitors of different media are very different in structure, cost, characteristics and uses.

The main functions are as follows:

(1) DC isolation: the function is to prevent DC from passing and let AC pass.

(2) Bypass (decoupling): Provide a low impedance path for some parallel components in the AC circuit.

(3) Coupling: As a connection between two circuits, AC signals are allowed to pass through and be transmitted to the next circuit.

(4) Tuning: system tuning of frequency-related circuits, such as mobile phones, radios, televisions, etc.

(5) Filtering: This is very important for DIY, and the capacitance on the graphics card basically plays this role.

(6) Timing: Capacitor and resistor are used together to determine the time constant of the circuit.

(7) Rectification: Turn on or turn off the semi-closed conductor switching element at a predetermined time.

(8) Temperature compensation: compensate the influence of other components on the lack of temperature adaptability, and improve the stability of the circuit.

(9) Energy storage: storing electric energy for release when needed. Such as camera flash, heating equipment, etc. Now the energy storage level of some capacitors is close to that of lithium batteries, and the energy stored in one capacitor can be used by a mobile phone for one day.

Step 5: Filter

The circuit that effectively filters out the frequency point of a specific frequency or frequencies other than the frequency point is a filter. The function of the filter is to let the signal of a certain frequency pass smoothly, while the signal of another frequency is greatly suppressed. It is essentially a frequency selection circuit.

In the filter, the frequency range through which the signal can pass is called passband or passband; On the contrary, the frequency range where the signal is greatly attenuated or completely suppressed is called stopband; The boundary frequency between passband and stopband is called cutoff frequency; The voltage gain of an ideal filter is constant in the passband and zero in the stopband. There is a transition band in a certain frequency range between the passband and stopband of the actual filter.

6, light emitting diodes

Light emitting diode (LED) is a semiconductor element. At first, it was often used as indicator light, display board and so on. With the appearance of white LED, it is also used as lighting. Known as a new light source of 2 1 century, it has the advantages of high efficiency, long service life and not easy to be damaged. When DC voltage is applied, LED can emit monochromatic and discontinuous light, which is one of the electroluminescent effects. Changing the chemical composition of semiconductor materials can make LED emit near ultraviolet, visible or infrared light. 1955, Rubin of ABC? Rubin Blancstein (born in 1922) first discovered the infrared radiation of gallium arsenide (GaAs) and other semiconductor alloys. 1962, Nick from General Electric Company? Nick Holonyak Jr. (born in 1928) invented the first practical visible light emitting diode.

Verb (short for verb) experience

This internship is another very important internship after the metalworking internship in the university, which lasts for one week.

At first, the teacher said that this internship was very simple. For me, because I remember welding in junior high school, it is not particularly difficult. The first day, I passed the teacher's explanation. Although I don't understand it very well, I still follow the teacher's steps step by step. Because I haven't welded for a long time, I was a little nervous at first and my hands trembled, so I was looking for and groping for the feeling of welding on the first day. There is not much welding equipment. I summed up the reasons after class. First, because of new chips and new attempts, I delayed the time and dared not solder the equipment. Second, blindly follow, not familiar with the placement position and way of equipment. I still need to discuss with my classmates to get the result, so I wasted a lot of time on the first day and delayed the progress later.

After the first day of exploration, I am looking forward to the next day's class. Because I began to learn from the first day, I did it faster. The welding of resistors and capacitors was basically completed the next day, and the time passed unconsciously during your welding. The teacher said the class was over and I wanted to continue welding. On the whole, I was satisfied with my performance the next day. On the third day, after yesterday's work, I continued to weld. Because I feel that the welding is almost done, I will test whether the diode on the circuit board can be lit. After testing, the diode did not light up. After asking, I realized that these are all welding problems and need to be detected by myself, so I repaired the' bad' parts that I thought were welded before and made continuous improvement. Due to the wet weather these two days, the copper ring we worked on had an oxidation reaction, which led to the tin not being soldered to the device normally. It took me a lot of time, but under the guidance of the teacher, after grinding off the oxidized part, I can work normally again. I am very happy to see my diode shine. This is the result of my own hard work, and I believe everyone feels the same way. On the last day, I continued to finish the unfinished work, such as installing the shell of the phone and finally testing it. I'm a little sorry that I can't talk when the phone rings, but I still feel very gratified. After all, I made it myself, so I have an obligation to buy it. As a souvenir and memory, I really enjoyed this process and felt really great! Through this internship, I gained the following knowledge:

First, when you encounter difficulties, don't be afraid, go ahead, don't be discouraged, make persistent efforts, and the result will be beautiful.

Second, let me feel the atmosphere of mutual help, cooperation and unity among my classmates in Qi Xin. In the process of welding, it is not enough for some equipment to do it by itself. With the help of students, they successfully welded their own equipment, which reflected the friendship and cohesion between students.

Thirdly, through this electronic technology internship, I learned about the installation, welding and debugging of integrated circuit phones and the functions of electronic components. Through practice, I made a phone call myself, which let me know the size of resistance, the different types and functions of capacitors, how to accurately grasp the position of solder joints and how much solder is needed. Finally, for my own small opinions, we must correct the mentality of quick success and instant benefit in the future work, and we must ensure the quality and quantity of any work, and it is also a very beautiful thing to find our own shortcomings. These are some of my experiences.

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