Read the good book "Operational Amplifier Parameter Analysis and LTspice Application Simulation" + Reading to learn about amplifiers

北方

Read the good book "Operational Amplifier Parameter Analysis and LTspice Application Simulation" + Reading to learn about amplifiers [Copy link]

1. Thoughts after reading

I am very grateful to EEworld for providing this opportunity to study. I usually read documents on the computer, but it is not so convenient to search, and it is not so pleasant to read without a book. When using analog design, you still need a few swords and spears. Among them, LTspice is the most conscientious free one. It is very necessary to have a book to start with.

2. Key parameters of the amplifier

Analog design has always been a pain point for localization because it requires accumulation and patent barriers. Unless you really intend to turn against them, all international patents can be declared invalid domestically. If you don't do xx like India, you can quickly get close. However, the shortcut that people take is often the most difficult one. Only when you figure it out yourself can you tell the truth.

Mr. T has always been the boss in analog. ADI is actually the champion in many fields, with parameters and indicators that are unique in the world. ADI's front end is always indispensable in advanced instruments such as high-end oscilloscopes. This book uses a lot of space to introduce ADI's products, as well as parameter configuration and selection guides. In fact, it is very practical. The amplifier parameter analysis part in Chapter 2 is the most practical.

After reading, I have a deeper understanding of many things that were not so clear to me before.

These parameters are actually very important. In different designs, some parameters are more important, and some parameters can be relaxed. Personally, I think the gain-bandwidth product and common-mode rejection ratio are the first to be determined in the selection, although they are not listed in the book, because the higher the gain-bandwidth product, the higher the price of the chip, the better the performance, and the parameters of the peripheral components also need to match the high-precision parameters. If the project requirements are not strict, be sure to choose a suitable data, don't be dazzled by the selection.

3. LTspice

I have used LTspice before, and it has a lot of free functions. This is mainly because LTspice was originally a paid tool software, and it is also very easy to use. ADI directly acquired it, and released it to ADI products, making it free to use, providing a large number of component libraries, and you can also download and update it for free, so it is inevitable that it is easy to use.

Many other free tools are self-developed and their performance is not that rich.

Even though LTspice is free, it is not closed and can still import products from other brands, but it needs to be customized. Many designs cannot completely use ADI products, but being able to add some modules yourself is actually beneficial to the use of ADI.

The most useful part of LTspice is actually the simulation part. Unfortunately, only the basic concepts of LTspice are introduced here. In fact, there are many more techniques and features that are better introduced below. LTspice has an oscilloscope function, which can display the waveforms of each test point of the analog circuit. This simulation part requires the configuration of a special language for input waveforms, which is similar to script, but difficult to understand. It is easy to use after understanding, but there is no manual and guidance, so it is still confusing to use. If it is reprinted, the instruction list and introduction of this part can be added, which will be more like a manual.

The parameter settings are unreasonable, and the waveform sometimes does not converge, which is also difficult to adjust. However, being able to adjust and discover problems on the simulator is a thousand times better than working on the hardware. Such a tool is really a powerful weapon. In fact, even if it is charged, many people will place orders to buy it.

Although the simulation part does not have many advanced functions, the most commonly used ones are all in it.

4. Summary

I have read this book and found it very rich in content. It also clarified many issues that I did not understand before. I am very grateful to the author for his hard work. In the LTspice part, I will systematically review it again according to this manual, which should be more rewarding. In LTspice, there are many example projects, which are very good for both introductory and advanced learning. I will study them in detail later.

soso

Looking forward to the sequel.