Abstract: What is analog? Everything we see, hear, and perceive in life is analog, from voice, music, and seismic activity to visual perception, voice recognition, and energy conversion and transfer. As a result, all electronic systems must interface with the world via analog electronics. Conforming these functions to today’s and tomorrow’s relentless demand for small, chip- integrated, mobile, battery-operated devices challenges analog engineers and researchers to design and create smart, robot-like solutions with state-of-the- art accuracy, speed, and extended battery life, which demands and requires training. Examples of the types of applications the field enjoys range from biologically inspired devices (e.g., pacemakers, nanotechnology probes, and so on) and commercial products (e.g., laptops, cellular phones, microsensors, and more) to military hardware (e.g., unmanned aerial vehicles, light-weight electronic equipment, etc.) and space exploration (e.g., remote meters, robots, and so forth). It is impossible to imagine engineering real-life solutions without the help and support of analog microelectronics.
Everything in the world is Analog : like vision, speech, touch, All our senses are analog. so in short circuits build to sense temperature, heart beats (ECG), blood glucose meter, radio waves, magnetic waves , light waves, sound waves etc..
There is no easy way to build a analog sensor.. All kinds of sensors have some sort of random noise (means lot of imperfections) associated with it so Analog design is often followed by signal processing algorithms implemented in digital circuits which when combined in one chip (Analog + digital) is known as Mixed-signal.
Another common example is touch screen in the cell phones. Based on different sensors used to create a potential difference based on the touch the ADC-analog to digital converter (Very important Analog Mixed signal design block) converts the potential difference created by touch into a equivalent digital value further drives the micro-controller unit to do the desired operation.
Good Audio players uses very different architecture of the ADC than touch sensor ADCs, which needs noise levels down by 96dB to have better sound quality not audible to human ears with in 20Hz-20KHz range else it would sound something like a old radio with lot of interferences.
The IOT( Internet of Things) have kicked up a huge demand in Analog Mixed signal designs space.