For example, we can only hear signals within a very small portion of frequencies from about 12 Hz to 20000 Hz, out of a very large number of frequencies in the Universe. We call this band of frequencies sound. We can only see signals with wavelengths from 380 nm to 740 nm and this spectrum spread we call light. We are limited in our perception, but these sensors are good enough for us. For the rest of the signals, we build electronic equipment to enhance our sensors.
From an article on the Mastering Electronics Design
Read the entire article: It’s an Analog World by Design by Adrian S. Nastase
Edited beyond Fair Use…so click on the link to read the full article
The signals we receive from Mother Nature are continuous. We don’t hear any discontinuity or choppiness in the sounds of ocean waves or bird songs and this is what makes the world analog. From our point of view, with the sensors we have, we interact with our world continuously. The signals have amplitude that can vary in time and are composed of a complex of frequencies.
So how is Analog defined? Merriam-Webster dictionary reads that analog is “of, relating to, or being a mechanism in which data is represented by continuously variable physical quantities.” The word comes from the ancient Latin, analogus, or Greek, analogos, meaning proportional. The term was adopted most likely due to the fact that the continuous signal we perceive is proportional to another continuous signal; or …
No matter the reason for which the word analog was associated with continuous electrical signals, the analog domain and the analog design are here to stay because we live in a continuous world as we perceive it. The interface between our world and our instruments and electrical equipment has to be analog. …
We need to amplify and filter the signals we capture … in analog domain and the circuits we achieve these operands and tasks with, are called Analog Signal Processing.
Analog signals and analog processing have their own limitations and that is why we digitize the signals, …
The design of the electronic circuits that manage the analog processing is very subjective. There are many ways to handle different tasks in the analog domain, …
The design cannot be automated as with the digital circuits. Sure, there are computer tools like SPICE based programs, which can verify and calculate the analog design, but the schematics have to be created by a human being in the first place. Maybe that is why we have so many computer tools to automatically create digital circuits, while the analog tools are still to be invented. Human creativity is difficult to be automated. Maybe a distant future, when artificial intelligence will approach creativity, might be able to automatically create analog circuits. But, will it?
Read the entire article: It’s an Analog World by Design by Adrian S. Nastase