Three in and three out, my ten-year power supply journey[Copy link]
This post was last edited by Mufan001 on 2018-6-28 17:33 Author: Nickname: Heartbroken After graduation, I was fooled into working in the power supply industry, and it has been 9 to 10 years. From production line, maintenance, after-sales, engineering, research and development, we have experienced ups and downs, joys and sorrows, and the future is still unknown. But isn’t it creating the future to summarize the past and grasp the present? The mind is the road, and experience brings experience! 1. Initial power supply test---a good habit after frying chicken The first job I got involved in power supply was in a small workshop making TV set-top boxes. The salary was 400 yuan per month. I was responsible for testing control panels. I worked for 10 days and got 50 yuan. It was quiet at noon that day. I saw the power supply at my colleague's position. Driven by curiosity, I plugged it in. There was a bang, which scared me to death. It turned out that there was a clamp under the bare power supply board. I regretted my stupidity and hurried back to my position and pretended to sleep. There were only two of us and the boss in this small factory. When he was confused after work, I pretended to be confused. I didn't confess my bad deeds until the day I left. Why didn't I do it? Installing and moving goods aside, I couldn't stand the boss's wife's cold eyes, and I didn't want to get involved in her family business, haha. After being scolded again, I asked my boss for my resume. I only learned one thing here, "sharpening the knife does not delay the chopping of wood." After that machine explosion, I always clean up my workstation before adjusting the machine, not even a small tin bead. I have obvious obsessive-compulsive disorder and I am quite timid, mainly because I am afraid of being scared by the machine explosion. I will clean up the place after finishing each task, which makes me feel good. And I hate those colleagues who don’t clean up the place after using it, because they leave a mess wherever they use it. Others say that those who don’t clean up the place don’t look like engineers, but a small action can help you do more without making a mess, so why not do it? I always emphasize that new colleagues I have led should do this. Of course, if you are like colleague A, who wants to rely on the things on the desk to show that he is busy at work, then I can only laugh. After all, this is his way of showing off to his superiors and bosses, and we cannot wipe out other people's financial resources. 2. Introduction to power supply circuits---learning is about tossing When I was in college, I was more interested in software, and I copied hardware circuits from my classmates. The so-called design was "designing" how to get the circuit of a three-good student. I didn't have much experience with power supplies. I only remember that the teacher mentioned switching power supplies in the color TV class. The thing that impressed me most was the starting resistor, because the teacher privately gave me an unforgettable metaphor. Ever since I changed the voltage and caused the machine to explode during maintenance on the production line, I began to systematically study the switching power supply circuit. At that time, I had been deceived into joining the factory for a week, saying that it was a one-month training, but in fact it was just an internship on the production line. At that time, I learned how to change the voltage from the maintenance veteran. Typical 431+ optocoupler feedback, Uo=2.5*{1+(R1/R2)}, so a 5V output power supply was changed to 12V by changing the series resistor, and the load exploded soon. The maintenance engineer was happy, but he couldn't explain the reason. I could only ask the old driver in R&D, he talked about a lot of turns ratios, duty cycles and so on, and I could only stare blankly. But after just one consultation, I was quickly recruited into the R&D department, and the old driver became my boss. But I didn't learn much from him, and I took the blame for him for the first time. 3. The first time I took the blame - social engineering When I was a student, I admired hackers for a while and participated in some activities. Only then did I know how to use social engineering. After graduation, I worked as a network administrator, but I gave up because I couldn't stand the reversed day and night. Since then, I have never had a deep relationship with software, and my interest has been abandoned. Last time I mentioned that I was recruited into the R&D department after an unintentional consultation. A few days after I went in, my boss A asked me to take a sample to a colleague A in the sales department. Let's call him Sales A. He was not there, so I put it on the table. Not long after, Sales A hurried over with the sample and asked if I put it on his desk. When he saw me nod, he started to curse. There was no swear word but it was worse than swear words. After listening for a while, I realized that he wanted a US plug, but he gave him a Chinese plug. In front of the whole department, including boss A, but he was silent. I didn't understand, and it was indeed me who took it. I had to use Ah Q's spiritual victory method. When I heard the dog barking, it was the first time. Sales A was a boastful person. It had nothing to do with technical ability. He just loved to brag. He came to the company a week earlier than me. He had a little background and money. Later, he often boasted to us. Both the black and white worlds had to give him face. Later, he had a disagreement with the boss and started a factory with others. One time, I met him walking on the road. He said that their factory no longer needed orders. They were all scheduled until the end of the year. It was only May Day at that time. I thought to myself, how low must the production be! After this incident, I realized that I might be able to learn technology from my supervisor A, but I had lost interest. Soon I changed supervisors. Later, I heard that my supervisor A had angered the boss because of his messing around in the company. After being targeted everywhere, he opened his own factory and his business was going well. After changing jobs, I joined the technical department. Small companies all do R&D and engineering together. When we met, my supervisor B said to me, "I can tell at a glance that you are a technical specialist." I don't know if this was a compliment or a mockery of me. Anyway, I am still working on technology, while he has long been a billionaire, living in an unknown house and having to think about which car to drive every day. The working environment is not like school. Most of the students at that time were still innocent, so there was no deep friendship after work. Over time, I became more and more lonely. People with temperaments are in this hypocritical world, and gradually understand that if you don't pretend to be cool, you will suffer, and if you don't get on the boat, you will wade in the water. Speaking of changing the boss, I was responsible for making samples. Aluminum shell power supplies of several hundred watts are mostly forward-pulsed by 3843 or half-bridges by TL494. I can also learn circuits after work. Boss B is more straightforward. The first decision to do things is to be fast and not to pay attention to details, but most of the PCBs he made for the first time need to fly wires or cut copper foil. Once I debugged one of his forward power supplies, the efficiency was only more than 50%. After checking for a long time, I found that he connected the freewheeling diode to the energy storage inductor. Haha, the sample sent to the customer was completely unrecognizable. Continue to connect. At that time, RCC was still used more for low power. The company had a lot of products, but they could basically be summarized in a few circuits. RCC circuit TL494 circuit UC3843 circuit 4. Exploding when you should be silent----Life needs to be recorded and summarized The time I spent in R&D making samples was very colorful. The sales girl was just acting like a spoiled child in front of me, but turned around and complained behind my back. It made people love and hate me. They say that beautiful women are the incarnation of the devil, and I finally experienced it. But this time didn't last long. My boss B switched to sales (what a wise choice!), and recruited chief engineer A from outside, a man from Northeast China with average skills, many friends, and a loud voice. At that time, there were many sample orders. The delivery time of the transformer could not meet the requirements of two or three days. Chief Engineer A had just arrived. The relationship with the transformer workshop was tense over the design of the new model transformer. The workshop did not accept the special winding method of the new product, but it could not pass the EMC test without winding it this way. When the stalemate came, the boss used money to solve it. But the transformers for the subsequent samples could only be made by our department. We had to select people from the department to specialize in making transformers. Chief Engineer A was not familiar with us either. He did not make this choice, but just confessed to us that one of us had to do it. When everyone was silent, I, who had the least experience and wanted to understand transformers, volunteered, but I did it for half a year. Be silent when you should be silent. But everything has its pros and cons. The trade-off between good and bad is a choice. Since you have chosen, do it seriously. When I first started making transformers, the equipment was a semi-automatic winding machine, which is probably still used in many factories. I had to use my hands and feet, and my awkward appearance made the whole transformer group laugh. But they all became my masters, and some of them would not help but give me some pointers when they passed by, so that I could quickly get started. During this half year, I couldn’t bear to be lonely. I made a table of all the company’s bobbins and cores, including parameters such as height, window size, Ae, and even summarized the power supply power, primary turns, primary inductance, leakage inductance of each transformer, and the comparison of different outputs of each model. I even recorded the diameters of all the multi-strand wires after twisting. Later, I didn’t need to look at the drawings when winding the transformer. I knew how much I could wind with each bobbin and wire. Sometimes when I just got a new drawing from Chief Engineer A, I said I couldn’t wind it, but he didn’t believe it, but the fact was that I really couldn’t wind it. So life requires continuous summary to make progress, small summary, small summary, big summary. After summarizing, experience will become experience. 5. Forced to be a supervisor---Life needs a little ambition Speaking of the time when I was making transformers on the production line, since I was a member of the technical department, I would actively or passively participate in many things. For some production line equipment, such as wave soldering, electronic load testing. Debugging and parameter settings of ultrasonic shell pressing machines and parts molding machines. And when making samples, I know the products of the entire factory very well. At that time, the head of the engineering department was about to leave, and Chief Engineer A asked me to take over. I am not interested in management, and I have proved that I am not a management material when I was a student. But I couldn't accept all kinds of threats and inducements, so I tried it again. At that time, there were only two people left in the project, one ME and one PE. The tiredness was acceptable, but for the engineering department, which connected the whole factory, it was like a target of public criticism. Any problem was handled by the engineering department first. So I admire the current engineering supervisor. But I didn't have a strong ability to withstand pressure, so I resigned in less than three months. I couldn't stand the pressure and resigned. The boss tried to persuade me to stay, and finally reached an agreement. After the new engineering supervisor came, I worked in R&D. I was naive and inexperienced. After the new engineering supervisor came, he was not very familiar with the factory and had to assist him. Soon I found out that he was specialized in wave soldering and knew nothing about power supply. Often, he had to ask me before signing a document. I had to go through the whole factory to find him to sign the documents given to me by others. This embarrassing situation made both sides a little unhappy. But he was a good person. After introducing my girlfriend to me, our relationship was very good. People are so realistic, haha! But I understand that it is difficult for such a chaotic factory and his personality to persist. Without full dominance, you can't resist those money wolves. After he carried his backpack and left in a chic manner, I had to deal with the aftermath, including his furniture, which was all taken over by me. He later joined a large company and suggested that I leave many times. I was very curious. Many of my former colleagues and friends suggested that I leave after they left. But I am too lazy and sometimes I can’t help myself. After my matchmaker supervisor left, I took over the job and waited for the next one to take over. In fact, the workload during that period increased rather than decreased. The difference was that there was someone in front of me acting as cannon fodder, so the pressure was not that great. What surprised me was that the engineering supervisor before I became the supervisor came back, so let’s call him “predecessor”. I think if it was me, I would never come back after I left. I thought I would return to R&D soon. But things did not develop according to the script. At first, my predecessor kept me for two more months on the grounds of insufficient manpower. But later, after Chief Engineer A gained a foothold in the factory, he recruited many of his old subordinates, including R&D engineers, structural engineers, and assistants. After he developed a few low-power products, he retired from the job and only managed people. His subordinates were all capable people who had worked with him before. They were smart. After the company gave him shares, he enjoyed a peaceful life. Later, I don’t know who revealed that Chief Engineer A was just an engineer who earned a few thousand yuan a month before he came. He had no talent and relied on bragging. But when he came here, he became a boss with an annual income of several million. Of course, I know who leaked the news. Wherever there is a conflict of interest in this society, there is darkness. As for my position, it was taken by a relative of Chief Engineer A who had just graduated. But at that time, I was looking for a wife and I had put everything aside. Love makes people lose themselves. There are several bosses in the company, and each boss is in charge of some departments. My boss B later told me that if there was any disagreement between the bosses, he hoped that I would stand on his side. But for these, I just wanted to stay out of it. I pretended not to understand many things and didn't ask about them, so that later I really became an outsider. People still need some ambition! Sixth, after-sales service. It is not easy to say I love you----Life is like acting The problems encountered in after-sales service are of various kinds. Due to different load conditions, they may be more headache-inducing than those encountered during R&D. For example, once in a machinery factory, the iron shell power supply we supplied caused the customer's large sewing machine to crash from time to time due to load response problems. The failure was not common, and the effect test was troublesome. After two months of continuous work, we were unable to help the customer solve the problem in the end. It was just because of some inherent phenomena of the power supply itself. Although customer complaints are all kinds of strange, fortunately I have the habit of taking notes, so until now, every time I encounter a familiar problem, I can easily solve it and be complacent. Customers are all kinds of people, and some are simply impossible to communicate with, but technology is reasonable. No matter what the other party's character is, you must first make your own products good. Speaking of this dark history of after-sales service, I don’t want to miss it too much. All that is left are the cases in the notebook. It is not surprising that you will fail at any time if you are impulsive. When your sense of responsibility cannot restrain your bad temper, failure has already come. For a long time, I couldn't get used to the situation of putting on a smiling face when being scolded by customers, so after a tantrum at a customer, my world became quiet again. Socializing is the biggest challenge in my life. I see through many hidden rules, but it is difficult to accept them. So I often prefer to deal with technology and gradually become silent. Even if others flatter me, I just want to have a clear conscience. Later on, it was difficult for me to adapt to the new environment, and others also had no way to adapt to me, and it was difficult to make new friends. After staying for a long time, everyone will understand. For example, if the boss assigns things that are not within his responsibility, he will be angry when he is unhappy, but he will always complete them on time. Although he can do the work, the boss is more or less gnashing his teeth, secretly hating this "turtle son" who is not happy with anything. So although he has a sense of responsibility, he is not active enough. I have been in the world for too long, and have seen too many people who are as close as brothers in front of each other, but hate each other deeply behind their backs. I can't help but think of the song I used to sing when I was a child but only understood when I grew up: "The sky when you look up is a man's sky The boy who once dreamed under the starry sky I don't know how high the sky is I don’t know how far the sea is But I swear to take you far away To the end of the sea and the sky ………… ………… The sky now is a dirty sky The stars can no longer be seen in the civilized sky The sky is not actually very high, and the sea is not actually very far away The human heart is actually higher than the sky and farther away than the sea I learned to lie and chase after fame and fortune Only when I got lost in reality did I discover my own vulnerability ………… ………… Seven. The road of technology---so close, so far Some time ago, I was helping a customer to rectify EMC. I measured the power supply alone, and the margin was already large, but the whole machine had a frequency point that was extremely high, which was nothing more than the crystal oscillator frequency point in the single-chip microcomputer. I didn't dare to start with the customer's high-end equipment. During the period, I was confused and connected the wrong line and it exploded once. Fortunately, only the capacitor exploded, otherwise the whole month would have been in vain. The customer's customer is in South Korea, and they were in a hurry to get the certification done. There was only one chance to make corrections, so they had to put a magnetic ring in series on the power output line. I didn't want to increase the cost for the customer, but with only 2 or 3 dB of margin, it was like walking on thin ice. This situation reminded me of the time I spent in the electromagnetic interference laboratory at the beginning of research and development. All the tests had to be conducted in an external laboratory, which was extremely expensive and stressful. It was hard to report back after spending money on the tests but failed. So after a whole day, I was exhausted physically and mentally. I had to come back to summarize, write reports, and modify BOM and so on. The most infuriating thing was that I was just a little bit short of the mark, but I couldn't make that 1 dB difference. After giving up many times, I suddenly got an idea, but I was still disappointed. It was like the tall building in front of me, which looked very close but was too far away. The most painful thing was that just when I wanted to continue, the test time was gone. I think everyone who has experienced these feelings has experienced them. For EMC, experienced people know how to control it from the source, while novices can only rely on trial and error. After trial and error, they find out the root cause and learn from it next time. This is experience, and what others teach is far less profound than trial and error. Technology is also an art, which requires not only experience, but also inspiration and patience. At the beginning of power supply design, various conditions and restrictions should be considered, otherwise even adding a small function may require starting from scratch. So the most feared thing is that when the development is almost completed, the customer wants to add something else, which will make people frustrated. Fortunately, the company has a laboratory, without huge testing fees, and can think about countermeasures quietly. When testing outside, I am too busy to think, and basically rely on routines. It's like playing whack-a-mole, hitting whatever pops up. Some methods have been thought of, but there are no parts. I will only use the transformer when there is no more damage. That means I have given up this time and can only wait until several transformers are made before testing. 8. The root of all evil --- salary road = ≠ growth road Salary is always the most sensitive and concerned topic in a company. Apart from the main reason, the amount of salary also represents the individual's hard work and status. So bosses, when you hear employees say that they feel they are not valued, you must understand that you have to increase their salary. This is a joke. The first salary I got was 50 yuan, as I mentioned before. My first job was 300 RMB per month in a small city in 2006. I worked as a network administrator in an Internet cafe near the school gate. I worked day and night, mainly helping newbies log in to games, watching football games at midnight, managing servers, etc. But I also had three "no's": no pouring tea or water, no washing clothes or sweeping the floor, and no watching movies at midnight. I was young at that time, and my salary was only enough for food and drink. My big belly was caused by drinking so much. Before I worked in power supply, I worked as an advertising salesman, and I almost joined the counterfeit currency team. My first power supply job was in 2008, with a salary of 800 yuan/month, and it was raised to 1200 after three months of regularization. At that time, I was learning things and didn’t pay much attention to salary, but this was wrong. Only the boss would say that you should work hard to learn technology in the first few years and don’t think about salary increase. That’s how I was fooled. When working, you should only talk about money and less about feelings! You have to learn technology and negotiate salary. If you want to negotiate salary, you have to be confident, and if you have to be confident, you have to study hard. After all, this is youth, which will never come back, and you are working hard! The company has the capital to waste talents, but you can’t waste your youth! I've gone off topic a bit, let's continue... In 2009, my salary rose to 2500/month. Some people say that if you want a big jump in salary, you have to change jobs. I don't disagree with this view. I have seen too many examples of people who suddenly became bosses with an annual income of tens of millions. But if I have to choose between money and interest, I will choose the job I like. It may be because I have never had to worry about food and clothing since I was a child, so I don't have a strong concept of money, and I don't have too much restraint, which leads to the fact that I am still a moonlighter. Of course, there are exceptions. For example, if the price is far beyond my heart, I will go all out. It can be seen that money is still the first priority. Oh, OK, stop talking nonsense and get back to the topic. I roughly calculated the average salary over the years, 3500 yuan/month in 2010, 5000 in 2011, 6000 in 2012, 7300 in 2013, 9000 in 2014, 11K in 2015... Nowadays, I can support a family of four by myself. I can afford to treat minor illnesses, but I will die if I get a serious illness. Besides, with the current price of goods, it will be stressful if the salary is a little lower. House, car, family... There is always a mountain pressing down. And from what I know, not many employees are satisfied with their salary, thinking that their ability exceeds this compensation or that they should get more than him... In fact, among the friends I know, except for those who have become bosses or switched to sales or other jobs, technical engineers have basically reached 10K or more, and the highest is nearly 30K. If it is higher, it is estimated that it is not a monthly salary but other means. Generally, it is between 10K~15K, and the skills are similar. Those with better eloquence will be higher. This is the situation I have come into contact with. But some people will say, I don’t even make 10K, isn’t that too hurtful? What I want to say is that people who have gained a lot have either paid their youth and accumulated experience, or have made a hundred times the effort, or have a lot of connections. If you have these, then what you lack is a good boss. Nine. Three people walking together---good teachers and helpful friends on the road of technology Speaking of the road of power supply, in addition to the road of salary and time, it is also the road of technical growth. If you can get a good master on the road, you can get twice the result with half the effort. If you get a good comrade (a like-minded person), you can encourage each other. I lament my bumpy road of power supply. It is a pity that I have not received any professional technical training and have not been blessed to follow any big names. Everything must be explored by myself. If I don’t understand, I will ask questions on Baidu or in the forum. I also developed a bad habit of asking questions without thinking when I encounter a problem. In fact, many things can be understood by thinking more and doing more, combined with basic principles, but I go far away and seem very unprofessional. 10. Thinking about life----time, money, dreams I have written so many words here and there, which just resembles my muddle-headed career in recent years. After I turned 30, I feel that time is more and more precious. I hope that every day can be more compact and valuable. I don’t know how to cherish my free time. The busier I am, the more afraid I am. I remember that I didn’t have any free time to take care of my family some time ago, so I had such a strong desire to learn. I regret every wasted time. But why do people always know how to cherish after they lose something? I remember that when I was a student, I had many dreams about the future. I wanted to be a teacher, a boss, a programmer, a hacker, and even a football star. I did work hard and struggled in these directions. But after graduation and work, I suddenly lost my direction in the face of this unfamiliar society and forgot my original intention. The gap in my heart may inspire fighting spirit, or it may make me confused and obsessed. However, today, is it too late for a middle-aged uncle to regain his dreams and set clear goals? Recalling my childhood, I liked to eat more and asked my grandfather for pocket money every day. When I asked in the morning, he would give me one or two cents, and then I would happily go buy snacks. When I asked my grandfather in the afternoon, I would always be scolded and couldn't get any money, but my grandfather would cut a small piece of apple or break one or two orange slices instead. Those were gifts from others and were already yellowed. Grandpa was not so good to all his grandchildren. My cousins were not treated this way, which led my cousin to say such a childish saying, "Grandpa is only my grandpa, not his grandpa." When I grew up, I also understood that because my father gave my grandpa living expenses, I could ask for money every day. Grandpa was a rare college student in that era. Before the criticism, he was still a landlord. Later, he helped people write couplets and other things for free, and became famous in the village. Grandma died very early. Grandpa's room was full of books. He often read and wrote. He also participated in many couplet competitions and often received some competition letters with only the upper couplet. But sometimes I would see Grandpa sitting alone at the desk, holding a piece of paper and crying silently. Later I learned that the paper was a letter from Grandpa's classmates from all over the country. However, until Grandpa fell down at the desk and passed away, his classmates were unable to reunite. Even a few years after Grandpa's death, I continued to receive such letters. It's a pity that we know and cherish each other but cannot meet! The most impressive thing is that the person who read the eulogy at Grandpa's funeral suddenly burst into tears and collapsed on the ground. That was one of Grandpa's classmates. That was also the most magnificent funeral procession in the village. I have written so much, and I will end with these things. Everyone has their own thoughts. But for me, "the money my grandfather gave me is for food, and the apples my grandfather gave me are also for eating." For my grandfather, it is gratifying that he can do what he likes until he is old, and he can really live and learn until he is old. For my father, without his efforts, I would not have achieved anything, and in the future, it will also be his achievement. They are grateful to those who give gifts, and they are also grateful to those who send off the funeral. For those who are destined to work together, classmates, colleagues, couples, comrades (like-minded), cherish them if you can.
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