Electronic devices are based on brilliant circuit ideas that are conceived once in beautiful minds by lots of imagination, intuition and emotions. However, time mercilessly covers up these pearls of human thought and we have to dig for long in the garbage of mediocrity to uncover them...
Fortunately, in many cases the fundamental ideas behind circuits are clear and simple; so, we may derive them routinely relying on our experience. But for no apparent reason some circuit ideas are still thoroughly disguised. As a result, there are lots of circuits that never get explained in classical electronics sources.
Why are basic circuit ideas hidden? Why do we have to find answers ourselves to all these reasonable questions: "What is the idea behind the circuit? Where has it come from? How has the circuit idea been evolving through years?" Let's try to reveal the mystery of this phenomenon.
Looking for an answer in original sourcesEdit
At first glance it would seem sufficient to read original (primary) sources to find out the ideas behind circuits. But there are obstacles that prevent us from revealing ideas in such a way.
Not every circuit originator (inventor, designer, scientist, etc.) has a gift for explaining and presenting circuit ideas. To invent a novel circuit structure does not exactly mean presenting the idea behind it in the best way (the art of creation does not always involve the art of performance). In many cases, even if professionals want to explain their own circuit ideas in the best way, they are not successful. A routine example: as a rule, poets and composers do not perform their works in the best way.
Lacking of explaining abilities is typical for hobbyists that prefer rather to do something than to explain in the best way how it operates. Authors of articles published in hobby magazines, books and web resources usually give ready-made circuit diagrams with concrete components and values but do not show why.
Willingness for disclosingEdit
Not everyone who invents a circuit wants to disclose their secrets for variety of reasons. Let's consider some typical examples.
Patents are classical examples of such a reluctance. Why are patent descriptions so difficult to understand for ordinary people? The reason is that inventors just do not want to make circuit ideas clear and understandable! An army of patent specialists help inventors to professionally hide their ideas. There is a contradiction in patenting: from one side, the inventor must to reveal the idea; from the other side, he wants to hide the idea. Actually, inventors do not want to share what they know with people; just the contrary, they want to keep it for themselves! If we compare patenting with Wikibooks idea, we can realize how deeply selfish patenting is.
It seems strange, but it is true that professionals very often hide circuit ideas. The reasons vary.
Inventors usually do not like to tell how they have invented circuit solutions. Maybe, they are afraid that revealing the circuit evolution will cloud their glory; so, they would like the ordinary people to think of inventing as a heavenly gift. In many cases, the way of inventing is even more valuable than the result of inventing. In other cases, it is more useful for understanding to imagine that the circuit is invented in a different than the actual way (i.e., the logic of understanding may differ from the logic of inventing). For example, few books (especially professional publications) explain the transistor operation; instead, they directly jump to the mathematical expressions instead of explaining its principle of working. Mathematical expressions are secondary part and are helpful for increasing the efficiency of circuit, they will not tell us the operation of circuit and how the circuit is designed.
Producers of electronic components are not interested in revealing circuit ideas; instead, they are interested in advertizing their wares (components, devices, etc.) For example, an EDN's article states that a low-resistive load may be cancelled by placing in parallel the same negative resistance. However, the author has not shown what the op-amp actually does to act as a negative "resistor" but he has not forgotten to show the type of the op-amp (Maxim's MAX4165 op-amp). Seeing such a concrete circuit reader is left with the impression that this is the only possible circuit implementation. If there are not such components as shown, reader will not be able to make the circuit; he has to wait until other manufacturers suggest their components:) Actually, the idea is extremely simple and intuitive: the op-amp "helps" the input reference voltage source by injecting the whole current needed through the load (see the picture on the right).
Design engineers scrutinize interesting and useful technical details about circuit solutions but, as a rule, they do not like to reveal circuit ideas in the introductory part of the materials. Professionals usually think that "the ones that know do not need explanations while the ones that do not know will never understand it". For example, in another EDN's article, the famous Bob Pease from National Semiconductor has shown useful tips about designing the popular circuit of transimpedance amplifier; only, he has "forgotten" first to show the general idea behind the legendary circuit. Actually, this is the same "helping idea" as above; only, here the op-amp's output is connected in series with the input source and the resistor. Thus it "helps" the input source by adding so much voltage in the circuit as it loses across the resistor.
After this short "excursion" through the world of the original sources we can already see the answer to the question, "Why are circuit ideas hidden?" Maybe, the main reason is that lots of actual authors actually do not like to explain circuits; they like to create them.
Looking for an answer in second-hand sourcesEdit
In circuitry, like in most areas of life, a few gifted people invent novel circuit solutions; then, an army of not so gifted, normal and poor people reproduces their ideas down the years. After such a reiteration valuable ideas can mutate and even vanish the same way that a sentence generally changes a little from person to person during a telephone game. It is even possible that the writer or teacher that present the circuit actually has not understood the idea behind it; as a result, readers or students will also not understand the circuit.
Well, let's prove these assertions. Imagine we are curious people that peek into various electronics sources in the hope of revealing circuit ideas. What do you think we will see?
Textbooks. If we turn over the pages of classical electronics textbooks, in the most cases (excluding The art of Electronics and the accompanying Student Manual), we will find there formulas, definitions and formal analyses. By using these quantitative means, authors (usually university lecturers) try to explain qualitative things. Why do they do that? Maybe, in this way they add more credits to climb the professional ladder? Or, if they are vain enough, just want to rise in the esteem of students? As a result, circuit ideas remain hidden for poor students.
Books. Maybe, we will manage to find out circuit ideas in traditional electronics books? Alas! Instead, we can most frequently see there ready-made circuit solutions to be analyzed in their complete, final and perfect form. Books claiming to show the basic circuit ideas (e.g., Floyd's Fundamentals of Analog Circuits) do not show any circuit idea although they are useful for other purposes. Even books pronouncing themselves as inventive do not reveal actually any circuit idea. For example, otherwise useful for technicians book Practical Electronics for Inventors actually does not show how to invent at least one new circuit!
Magazines, conferences, dissertations... In many cases, they are exploited by poor university lecturers and scientists for the purposes of their career. In order to satisfy academic requirements, as a rule, such materials are formal, dull and vague. They serve mainly other poor people to use them, in order to write more poor materials that will serve other poor people... and again and again... Such "reputable" materials have usually many authors that cite each other thus implementing the principle "I to you, you to me". Obviously, we will not find there the truth about circuits...
Hobby books, magazines and resources. As they are intended mainly for doers than for thinkers these sources prefer to give ready-made circuits with concrete electronic components and values. This is all very well if the circuit runs successfully, but what do we do if it doesn't? How do we repair it, if we do not know how it functions?
Lecture halls. Maybe, we will find the truth about circuits in university lecture halls? Alas! We will see there how lecturers try to explain circuits skilful juggling with formal methods; they treat poor students as computers, not as human beings. This approach frequently leads students to absurdity analyzing something not really knowing what it is. Why is this manner of teaching widely used? Maybe, it is just convenient...
Educational laboratories. Then let's peek into modern laboratory; maybe, there they will show circuit ideas? However, even the most perfect instruments and simulating programs do not reveal circuit ideas, if instructors compel us to use them in a traditional way (measure Ib and Ic, calculate ß, write a report, etc.) Instruments do not have imagination, they can't show circuit idea.
Web resources. Maybe, it is our last hope to find out circuit ideas and maybe, it is our biggest disappointment... Browsing through the web we see that only the way of presentation has changed but the content is the same...
After this "excursion" through the world of the second-hand sources we can already see more answers to the question, "Why are circuit ideas hidden?" Maybe, the main reason is that lots of secondary authors actually do not like circuits. They know circuits but do not understand them. Circuitry is more a routine job than a favorite pursuit for them. They have not a vocation for explaining circuits; so they can work with the same success in other completely different areas.
For various reasons, in the most cases great ideas behind circuits are hidden or mutated. It turns out that there is no place for revealing basic circuit ideas. No one shows what we, human beings, actually need - what basic circuit ideas are, where new circuit ideas come from and how they have been evolving through years.
Obviously, nobody can perform our work. We have to form by ourselves universal methods and skills for revealing the basic ideas behind circuits and then to enrich them continuously. In order to understand how circuits act, we have to revolve the ideas in our mind, in order to associate them with our former knowledge of life.
How to Hide Circuit Ideas gives useful tips for beginning "idea hiders" (a humor:)
How to Kill Circuit Ideas gives useful tips for beginning "idea killers" (a humor:)
Why Formulas Cannot Explain Circuits explains why formulas hide circuit structure and causality (a humor:)