Graphic of transistor
Transistors share the same principle of using N-type or P-type silicon as diodes but in a more complicated layout. In a transistor two P-N type junctions are placed back to back. In effect one type of semiconductor material is sandwiched between two others. Silicon chips can hold many transistors, with the transistors acting as Boolean (logical) gates.


  • In 1959, engineers working at manufacturer Texas Instruments constructed the first integrated circuit, a semiconductor circuit containing more than one transistor on the same base. The first integrated circuit lacked processing power: containing only six transistors.
  • By 1982, technology have advanced so that the company Intel were able to introduce a 80286 chip with 134,000 transistors. Later generations of microchips work on similar principles, but are more advanced with more transistors on each chip and with the ability to process a greater number of instructions per second. Pentium III microprocessors which sit in many office and home computers in current use, may contain more than 27 million transistors on a single chip die; more recent Intel microprocessors have several hundred million transistors.
Amazon Books
Image of Principles of Transistor Circuits: Introduction to the Design of Amplifiers, Receivers and Digital Circuits
Author: S. W. Amos
Publisher: Newnes (1994)
Binding: Paperback, 400 pages