Question

Transistors are a fundamental building block of modern computers. Describe the basic properties of a transistor (what does it do?). How did computers work before transistors were invented? Which generation of computers first used transistors? How many transistors are in the CPU of a modern consumer-level PC?

Answer 1

• A transistor, also known as BJT(Bipolar Junction Transistor), is a current driven semiconductor device which can be used to control the flow of electric current in which a small amount of current in the base lead controls a larger current between the Collector and Emitter. They can be used to amplify a weak signal as an oscillator or as a switch

• The first generation computers were known for using vacuume tubes in their construction. The generation to follow would use the much smaller and efficient transistor. Vacuume tubes : Any modern digital computer is largly a collection of electronic switches. These switches are used to represent and control the routing of data elements called binary digits. Because of on-or-off nature of the binary information and signal routing the computer uses, an efficient electronic switch was required. The electronic computer used vacuume cubes as a switches, and although that worked they had many problems.     The type of tube used in early computer was called a triode. It consist of a cathod and plate, separated by a control grid, suspended in a glass vacuume tube. The cathod is heated by a red hot electric pilament, which causes it to emit electron that are attracted to the plate. The control grid in the middle can control this flow of electrons. By making it negative, to cause the electrons to be repelled back to the cathod, by making it positive, you cause them attracted toward the plate. Thus, by controlling the grid current you can control the on-or-off of the output of the plate. Unfortunately, that tube was inefficient as switch. It consumed a grate deal of electric power and gave off enormous heat-a significant problem in the earlier system.

• The second generation of computers used transistors.

• Around 781 million transistors are there in the CPU of modern consumer-level PC