Plan: Analog electronics

Analog electronics
The world of electronics is all about electrical circuits, electronic components, and interconnected technologies. All these elements can be primarily categorized as digital, analog, or a combination of both. However, here we will be focusing on the basics of the analog category in detail. 
Analog electronics is a branch of electronics that deals with a continuously variable signal. It’s widely used in radio and audio equipment along with other applications where signals are derived from analog sensors before being converted into digital signals for subsequent storage and processing. Although digital circuits are considered as a dominant part of today’s technological world, some of the most fundamental components in a digital system are actually analog in nature.
In order to understand the concept, let’s first try to analyze the word ‘Analog’.
What is Analog?
Although computers are typically viewed as a modern invention involving electronics, computing predates the use of electrical devices. The ancient abacus was perhaps the first digital computing device. Analog computing dates back several millennia as primitive computing devices were used as early as the ancient Greeks and Romans, the most known complex of which being the Antikythera mechanism. Later devices such as the castle clock (1206), slide rule (c. 1624) and Babbage's Difference Engine (1822) are other examples of early mechanical analog computers.
The introduction of electric power in the 19th century led to the rise of electrical and hybrid electro-mechanical devices to carry out both digital (Hollerith punch-card machine) and analog (Bush’s differential analyzer) calculation. Telephone switching came to be based on this technology, which led to the development of machines that we would recognize as early computers.
Integrated circuits
The circuits that were made previously were large and bulky, consisting of circuit components like resistor, capacitor, inductor, transistor, diodes, etc., which were connected with copper wires. This factor limited the use of the circuits to big machines. It was not possible to create small and compact appliances with these big circuits. Moreover, they were not entirely shockproof and reliable.
As it is said, necessity is the mother of all inventions. So there was a need to develop smaller size circuits with more power and safety to incorporate them into devices. Three American scientists invented transistors that simplified things to quite an extent, but the development of integrated circuits changed electronics technology’s face.
The integrated circuit is a fundamental concept of electronics that builds on other basic concepts previously discussed in our syllabus. Therefore, for a quick reference, go through the articles listed below.
An integrated circuit is a complex layering of semiconductors, coppers, and other interconnected materials to form resistors, transistors and other components. The cut and formed combinations of these wafers are known as a die.
The semiconductor wafers that make up the ICs are fragile, and the connections between the layers very intricate. As an IC die is too small to solder and connect to, the ICs are packaged. The IC package turns the delicate and tiny die into a black chip we are familiar with. The IC package encapsulates the integrated circuit and transforms it into a device that we can easily connect. There are many different types of packages, each having unique dimensions and mounting types as shown in the figure.
What are integrated circuits?
An integrated circuit (IC), sometimes called a chip, microchip or microelectronic circuit, is a semiconductor wafer on which thousands or millions of tiny resistors, capacitors, diodes and transistors are fabricated. An IC can function as an amplifier, oscillator, timer, counter, logic gate, computer memory, microcontroller or microprocessor.
An IC is the fundamental building block of all modern electronic devices. As the name suggests, it's an integrated system of multiple miniaturized and interconnected components embedded into a thin substrate of semiconductor material (usually silicon crystal).