The Transistor was Invented in 1948 at Bell Telephone Laboratories

The invention of the transistor was an unprecedented development in the electronics industry. It marked the beginning of the current age in the electronics sector. After the transistor's invention, advances in technology became more frequent, the most notable of which was computer technology. The three physicists who invented the transistor; William Shockley, John Bardeen, and Walter Brattain were awarded with the Nobel Prize. Considering the inventions that the transistor paved the way for, one could argue that it was the most important invention of the twentieth century.

From Germanium to Silicon

Transistors were originally manufactured using Germanium. This was the standard for the first decade of transistor production. The Silicon-based transistors that we're used to seeing today were adopted because Germanium breaks down at 180 degrees F.

Functions of a Transistor

A transistor's functions consist of amplification and switching. Let's use a radio as an example: the signals that the radio receives from the atmosphere are extremely weak. The radio amplifies these signals through the speaker's output. This is the "amplification" function.

For an analog radio, simply amplifying the signal will cause the speakers to produce sound. For digital devices, however, the waveform of the input signal needs to be changed. For a digital device like a computer or MP3 player, the transistor needs to switch the signal state to a 0 or 1. This is the "switching function"

Even more complex components like Integrated circuits made from Liquid Silicon Infiltration are basically collections of transistors.

Resistors and Transistors on a Single Chip

Originally, discrete resistors and transistors were mounted on the same printed circuits boards.Later on, transistor chips with built-in resistors were developed as digital transistors.Using digital transistors in designs has : 1.They require less area to mount components on a printed circuit board. 2.They require less time to mount the components on a printed circuit board 3.This reduces the number of components needed.

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