Glossary / Semiconductors
Boolean algebra
Mathematics that represents true and false as 1 and 0 and calculates with AND, OR and NOT much as with addition and multiplication. The foundation of digital circuit design.
In 1847 the English mathematician George Boole wrote logical reasoning as algebraic equations that could be calculated[1]. At the time it was a matter of logic, with no connection to machines.
In 1937–38 Claude Shannon showed that switches in series act as AND and switches in parallel as OR, turning circuit design into Boolean calculation[2]. Akira Nakashima at NEC reached essentially the same idea at about the same time. This correspondence is why switching transistors on and off can compute.
Related terms
- TransistorA semiconductor device in which a small signal controls a larger current, so it can amplify or switch. The basic component of all electronics.
- CMOSA circuit style that pairs the two opposite types of MOS transistor. Current flows only at the moment of switching, so power consumption is tiny.
On the timeline
Sources
- G. Boole, “The Mathematical Analysis of Logic,” Cambridge: Macmillan, Barclay, and Macmillan (book) (1847).
- C. E. Shannon, “A symbolic analysis of relay and switching circuits,” Trans. AIEE 57, 713–723 (1938).