"If you want to do a good job in the design of analog circuits, it is not enough to simply break down some circuits, so that you can understand them, but you must have a deep understanding of operational amplifiers, which is the cornerstone, if you really understand this device, your analog circuit level can reach the first level. Pen × fun × Pavilion www. ｂｉｑｕｇｅ。 info" Liu Chen said.

Mingyuan said disapprerovingly: "There are so many operational amplifiers, the main feature is not that they are short and broken, and all the design basis is based on this." ”

"If your knowledge is only at this level, then you can only stay at the beginning stage, even if you have a lot of experience. Liu Chen said unceremoniously, "There are two difficulties in operational amplifiers, one is frequency response, and the other is feedback, especially feedback, there are very few people who can really understand it, you design a sine wave waveform front circuit and then add a comparator variable square wave to show me." ”

"What's so difficult about this!" Mingyuan was quite unconvinced, walked over and drew quickly on the board on the side, and quickly made a circuit design, and added capacitors and resistors.

"Solve the equivalent circuits with or without Miller compensation for the op amp, find the principal pole and the bandwidth expression, and eliminate the uncertain effects near the zero point. ”

Mingyuan opened his mouth and was a little stupid, what is this, he doesn't understand it at all, confused.

Liu Chen shook his head and said: "The circuit you designed in this way can't even determine the specific values of resistance and capacitance, but it is just a function, if it is used to process sound signals, I don't know how much noise it will cause, you don't even have the concept of bandwidth, how to deal with the frequency response of sound? You should also know that this is an important indicator of MP3." ”

"Enter the software programming processing in the main control chip, even if the algorithm is not concise enough, the realization of the function has little impact on the sound quality, the key is the analog circuit of input and output, the first level of realm I told you before is to be able to calculate by hand, look!"

Walking over, Liu Chen kept writing, and the complex calculations formed a wonderful beauty, and finally came up with several range parameters.

Seeing the full board of calculations, Mingyuan had a deep sense of frustration, and he truly realized the meaning of the three realms that Liu Chen said, it turned out that he had always been a frog sitting in a well and watching the sky, and he couldn't be complacent all day long.

He lowered his head in shame, he was completely sure that the young man in front of him was the chief engineer of Yinba, he took a breath and asked, "How did you get to this point?"

Liu Chen said with a smile: "If you want to use the operational amplifier well, the best way is to design it, understand the internal structure in detail, how the differential input tube converts the input voltage into input current, how to form a current mirror, what is the DC paranoia, rather than the surface of the virtual disconnection, in your mind intuitively see the so-called flow surge, just like the cow, as if you see through the flow direction of every capillary in your body, this is the second realm." ”

The gap is too big!

The more Ming Yuan listened, the more frightened he became, he was just getting started, and the young man in front of him had at least reached the second layer! A new world opened up in front of him, originally he was complacent, but because he couldn't find the direction of progress, now he knew how small he was.

The frenzy in his eyes became more and more intense, and he grabbed Liu Chen's arm and said, "I want to learn, I also want to reach this realm, can you teach me?"

"Yes, you can, but you can't be taught for no reason, and you won't be able to teach it for a while, if you're willing to join the sound master, it's much more convenient. ”

Mingyuan was a little embarrassed, scratching his ears and cheeks very anxiously, and said embarrassedly: "But I ...... I ......"

Seeing this, Gong Hui said, "Is there any difficulty with Teacher Mingyuan?"

He hurriedly waved his hand and said, "Don't mention any teacher, I'm ashamed to death, it's just me...... Because I didn't study hard in college, I didn't take the fourth level exam, and I didn't get my degree certificate, so I was a dropout. ”

When I was looking for a job, I ran to the electronics market as a maintenance worker, and I became famous step by step, but I was also at ease.

"Why is it difficult to say, we never pay attention to academic qualifications and certificates, but the real technical level. Liu Chen said with a smile.

"But I'm used to being free and loose, and I don't like to be managed. Mingyuan really wanted to learn from Liu Chen, but he also understood his own problems.

Most of the technical personnel are like this, Liu Chen knows this very well, he himself is also very busy with other people's noise, when he was a researcher in a foreign company, he was the most annoying and complicated interpersonal relationship and intrigue, and the technical personnel were like politicians one by one, but now he is not like this in his own company.

"You can rest assured, under the framework of the whole company, the technical staff is divided into small groups, not subject to anyone's jurisdiction, completely free, only need to complete the final result, just like your current work mode, and in view of your poor English, I will assign you a master's degree student to become the first free team of the company. ”

"Really?" Mingyuan has never heard of this model, and it is too unconventional, so it couldn't be better.

"Of course, Lan Jun and Sister Gong, I also hope that the two of you will understand my philosophy, technical personnel can only exert the greatest creativity and efficiency in the most free environment, and don't interfere arbitrarily. ”

The two nodded, Lan Jun knew after contacting Liu Chen and Kang Wenbin, once these people started to use technology, they ignored their words and didn't recognize their six relatives, and they definitely had to stay away at this time.

It is Liu Chen's atmosphere of technical freedom that makes Yinba show ultra-high efficiency in the next development, and the value created per capita makes those scholars who study company management puzzled.

After determining these things, Mingyuan couldn't wait to ask, "How should I start studying?"

"It's easy to say, first read through Razavi's classic book Design of analog ICs five times, and then read all the nearly 20 years of papers on op amps on JSSC for a preliminary understanding, and you will reach the second level. Liu Chen said with a grin.

Mingyuan instantly turned into a bitter gourd face, but he was never afraid of hardship when learning techniques, and suddenly asked curiously, "Have you reached the third level realm?"

"In fact, there is a fourth level of realm on top of these three realms. ”

"Huh? What's that?"

"Don't be in a hurry, you will naturally understand what it is, and I believe that you will be able to reach this level as well, and we will develop epoch-making products together." ”

"Okay, I'll start learning it now. Mingyuan's enthusiasm was unprecedentedly high, and after collecting the information, he sat down and watched it directly, Gong Hui and Lan Jun were stunned, this technician is really crazy. (To be continued.) )