The Physics Behind Electronics

"The Physics Behind Electronics" is not a book about electronics; it is a book about physics. Instead of focusing on electronics as an art, its primary goal is to provide the reader with an approach that emphasizes the physical phenomena underlying the function of electronic circuits, followed by their practical implementation. Electronics serves as a workbench for learning physics, and vice versa. The target audience includes advanced undergraduate or graduate students in physics or related disciplines who are familiar with the basics of electromagnetism and real and complex calculus. Additionally, it caters to individuals with empirical knowledge of electronics who wish to deepen and strengthen concepts often overlooked. Traditional textbooks treat electronics as a set of techniques, reflecting an era when physicists needed to develop circuitry for experiments, mastering details of analog and digital electronics. However, the increased availability of affordable acquisition boards and user-friendly software has diminished the need for proficiency in electronic circuit design. This shift has altered the perception of the relevance of topics that were once crucial in university courses. Nevertheless, physicists are still required to master concepts such as stability, impedance matching, noise, and understand the perks and limits of signal sampling. In other words, physicists still need to comprehend the physics behind electronics. The book begins with linear time-invariant systems and feedback, powerful descriptions of numerous physical phenomena. As natural follow-ups, the book delves into the design of circuits relying on operational amplifiers' versatility and subsequently oscillators, specifically their dissipation-countering implementations - a topic encompassing systems as diverse as the heart, violin strings, and GPS clocks. The content then progresses to the Nyquist-Shannon theorem, which dictates when a discrete number of measurements exactly reproduces the seemingly infinite information in a continuous signal. The basics of digital electronics are explored with an emphasis on state-sensitive and clock-sensitive operators. The book also provides an overview of electronic devices properties implementing conversion between the analog and digital worlds. The final part addresses scenarios where frequencies are so high that wires become waveguides and when ubiquitous noise sources, due to thermal agitation of electrons and the corpuscular nature of current, cannot be ignored. Theoretical explanations are complemented with a collection of solved exercises. Interspersed with the theory chapters are "in-the-lab" sections explaining how to conduct experiments using relatively affordable kits, instrumentation, and a minimal understanding of electronic prototyping on breadboards.