Anant Agarwal and Jeffrey H. Lang, Foundations of Analog and Digital Electronic Circuits, Morgan Kaufmann, 2005.

This textbook offers a comprehensive introduction to electronic circuits, including the material covered in Electrical Foundations and way beyond.

Kenneth J. Breeding, Digital Design Fundamentals, 2nd edition, Prentice-Hall, 1992.

Breeding’s book is a little dusty but well suited for self study, and contains valuable information about digital design that many modern texts omit in favor of more fashionable material.

William J. Dally and R. Curtis Harting, Digital Design: A Systems Approach, Cambridge University Press, 2012.

Digital Design is a contemporary text with many practically oriented examples and insights, that covers the breadth of applied topics relevant for today’s digital engineers.

Georges Ifrah, The Universal History of Numbers, John Wiley & Sons, 2000.

If you are interested in the history of numbers, independent of digital circuits, this is the book for your coffee table.

Randy H. Katz, Contemporary Logic Design, Benjamin-Cummings, 1994.

I recommend this book as complementary reading, if you are looking for a gentle introduction to Boolean Algebra, Combinational Logic, and Sequential Logic.

Zvi Kohavi and Niraj K. Jha, Switching and Finite Automata Theory, 3rd edition, Cambridge University Press, 2010.

Kohavi’s classical text presents the foundations of digital logic with a theoretical touch.

Donald E. Knuth, The Art of Computer Programming, Volume 4A, Combinatorial Algorithms, Part 1, Addison-Wesley, 2011.

Volume 4A of Knuth’s bible covers numerous aspects of the foundations of computer science at the bit-level including Boolean algebra and logic minimization with plenty of inspirational examples.

Arthur J. Lohwater, Introduction to Inequalities, unpublished course notes reproduced online, 1982.

This mathematical treatise contains an inspiring collection of useful inequalities and their applications, including the relationship between arithmetic and geometric means.

Edward J. McCluskey, Logic Design Principles, Prentice-Hall, 1986.

McCluskey’s text is outdated in some respects, but contains a detailed account of the early methods on Logic Minimization that have passed the test of time.

Elliott Mendelson, Schaum’s Outline of Theory and Problems of Boolean Algebra and Switching Circuits, McGraw-Hill, 1970

This text offers a mathematician’s perspective on Boolean Algebra and Switch Logic.

Gilbert Strang, Calculus, Wellesley-Cambridge Press, 1991.

Strang’s Calculus is a must-have for all students interested in the topic.

Ivan Sutherland, Bob Sproull, and David Harris, Logical Effort: Designing Fast CMOS Circuits, Academic Press, 1999.

This book introduces the Method of Logical Effort.

John F. Wakerly, Digital Design: Principles and Practices, 4th edition, Pearson Prentice Hall, 2006.

Wakerly’s textbook is an excellent introduction to the topic of digital design from the practitioner’s perspective.