Five stages to judge your circuit design ability

The methods for judging circuit design capabilities that are widely circulated on the Internet can be roughly divided into two categories: one is biased towards "metaphysics", for example - the article "Nine Levels of Circuit Design", the content is mysterious and mysterious, and can reach the highest nine-level standard. , there may not be many people on the planet. If you practice according to this standard, you will have to go crazy. In comparison, the other type of judgment criteria is more scientific, objective, and more common, such as the article 100 Experiences in Analog Electrical Design. This standard focuses on the amount of accumulated knowledge points, or it focuses on quantity and ignores quality. For example, Li Ao can recite more than 30,000 Tang poems, but he cannot write "Moonlight in front of the Window", which is a magical masterpiece. The fine writing comes from it. Affected by this method, many graduate students in the pot are addicted to reading papers all day in order to pursue the number of knowledge points. They often hear netizens say: I write one paper a day.

In comparison, the following design ability judgment criteria may be more scientific and effective, have more practical significance, and provide certain learning direction guidance.

At the first level, the stage cannot be judged.

For example, find the circuit shown in the picture below. The component parameters are all marked. You can directly draw the PCB, solder, and power on. If the function is normal, it is over. Because there are no design actions during this process, there is no way to judge.

The second level is the entry-level design stage.

This stage is to design a circuit that meets the performance index requirements based on the given circuit structure and related parameter constraints or conditions.

For example, in the figure below, the circuit has been determined to be a non-inverting amplifier. Given Av, just determine the two resistors Rf and Rg according to the formula.

The third level is the stage of possessing primary design capabilities.

This stage refers to the given circuit structure and the derivation of parameter constraints and trade-off principles based on the final design index requirements.

For example, in the picture above, the requirement is to use a non-inverting amplifier to design a circuit with Av=10. How to choose the two resistors more appropriately.

The fourth level is the intermediate circuit design ability stage.

Be able to reasonably select the required circuit structure, or be able to reasonably modify the circuit structure according to the indicators and provide a design plan that meets the requirements.

For example, you only know the gain, PSRR, CMRR, etc. of the amplifier you want to design, and select or modify the circuit structure so that it can complete all indicators.

The fifth level is the advanced circuit design ability stage.

Designers at this stage are almost mature, and are specifically characterized by their ability to flexibly improve applications, innovate and develop, their ability to solve problems easily, their ability to arrange for maximum energy efficiency in an eclectic way, and the value of each component in the circuit. Just right, not boring or angry. Finally, the potential capabilities of the circuit are maximized.

(It seems that Intel fully meets these requirements, but many companies in Europe cannot do this, so its circuit performance is regular and ordinary, while Intel's is very weird)

Note: Different industries may have different requirements, so the performance will be different, so it cannot be applied mechanically. But generally speaking, analog circuit design in different industries can always be summed up into four major parts: circuit/system/process/CAD, but the focus is different. For example, when designing discrete components, the process requirements will be weak.

Which stage are you in now after reading it?