Electronics

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Electronics

Electronics is, without a doubt, the fastest growing science of recent decades. This is because it has penetrated virtually all fields of human activity. Thanks to electronics, we enjoy digital clocks, cell phones, computers, televisions, video games, sound equipment and an endless list of products that have forever changed the way we live, work and interact with others.

Electronics and electronic systems are practical applications of the general principles of electricity. Electricity is a form of energy caused by the movement of tiny particles called free electrons. These particles, when circulating massively through certain materials, constitute electrical currents and produce important physical effects such as light, heat, movement, sound, magnetism, etc. Electronics deals primarily with the control of electric currents and, therefore, the effects produced by them. In other words, electronics is the science of domestication of electrons. Modern electronics have been driven primarily by the development of components to manipulate electric current in many different ways. Some of these components have been key in this process. The first one, which represented the passage from the electric age to the electronic era, was the vacuum tube or bulb, invented in 1906. Subsequently, the transistor (1948), the integrated circuit (1962), the microprocessor (1974) and the microcontroller (1982).

It is common that when a person wants to enter the fascinating world of electronics, they do not know what they should learn, what topics to master and, in what general order to cover those topics. A good starting point to get an idea of what is important to learn and in what order, is shown in Figure 2. This diagram provides an overview of the basic elements involved in the design of electronic devices.

At the top of the image comes the theory. This involves learning about voltage, current, resistance, capacitance, inductance, and various laws and theorems that can help you predict the size and direction of voltages and currents within circuits. As you learn the basic theory, you will know passive components such as resistors, capacitors, inductors, and transformers.

Next on the line come discrete passive circuits. These include current limiting networks, voltage dividers, filters, dimmers and so on. These simple circuits, by themselves, are not very interesting, but they are vital ingredients in much more complex circuits.

Having learned about passive components and circuits, he goes on to discrete active devices, which are constructed from semiconductor materials. These devices consist primarily of diodes (one-way current flow gates), transistors (electrically controlled switches / amplifiers), and thyristors (electrically controlled switches only).

Once you have covered the discrete active devices, continue with the discrete active / passive circuits. Some of these include rectifier circuits (ac-dc converters), amplifiers, oscillators, modulators, mixers, and voltage regulators.

To make things easier for the circuit designer, manufacturers have created integrated circuits (ICs) that contain discrete circuits - such as those mentioned in the last paragraph - which are placed inside a small silicone chip. The chip is usually inside a plastic package, where tiny internal wires connect the chip to the external metal terminals.