What is the "transistor" in the computer doing?

One of the semiconductor devices built in almost all electronic devices such as televisions, mobile phones, and PCs is "A transistor"is. Although I have heard of the name, actually it is not generally known what kind of role the transistor plays in electronic equipment, and even if I read the transistor's Wikipedia it is too professional to understand it There should be people, too. A movie explaining in an easy-to-understand manner what the transistor is doing with the electronic device "How transistors work"Has been released.

How transistors work - Gokul J. Krishnan - YouTube


Modern computers have evolved as much as they can change our lives.


This is the result of many innovations born over time.


What can be called the foundation of many innovations is called a transistor.


All computers are "machines that perform mathematical operations". An old tool that behaves like a computer, say abacus, is a device that manually performs mathematical operations. Physically enter the number and the abacus will display the entered number in its own way.


The modern computer, the so-called PC, has the same principle, but the PC expresses the entered number by voltage.


Most PCs are "Boolean logicUsing the theory that.


Boolean logic has two logical conditions "true" and "false" ...


The two are represented by binary numbers "1" and "0".


Also, "1" and "0" are represented by the presence or absence of voltage.


Logically computing "1" or "0" expressed by positive or negative of this voltageLogic circuitIt is what is called.


This logic circuit performs logical operation and outputs "1" or "0" to the computer.


Logic circuit is "Logical AND"ORThree basic logical calculations "negation" are performed.


For example, the logical product sometimes called an AND operation is limited only when two input values ​​are "high voltage", that is, "1" ...


"1" is output.


Logical operations such as logical sum and negate are input and output with the same mechanism.


In order to perform complicated operations such as addition and subtraction, multiple logic circuits may be combined.


Computer programs consist of instructions to electrically perform these logical operations.


In order for the program to perform a logical operation, a device that gives an accurate voltage to input "1" and "0" is necessary.


It is an early-stage computer (electronic computer) developed in the United StatesENIACThe


"Vacuum tube" was used as a device giving an accurate voltage.


However, ENIAC is as large as the tennis court, it is an unexpectedly large computer with a weight of 30 tons, and it is said that vacuum tubes that need heating are devices that can not bear to support the operation of ENIAC Thing.


Evacuated tubes are broken one after another in the ENIAC test conducted every day ......


Even in an examination for only one hour, a general house consumed approximately 15 times the electric power consumed per day.


A transistor appeared on behalf of the vacuum tube.


Among the transistors, NPN type transistors can be made of silicon as a material and can be set to a negative potential like a vacuum tube.


The part where the emitter (left) region and the base (middle part) contact each other and the part where the base and collector (right) contact each other is "Pn junctionIt is called "electricity if the voltage reaches a certain value, and will not pass electricity if the voltage is low. In short, the transistor is like a switch for passing electricity, simply, it is possible to send the voltage to the computer more accurately than the vacuum tube.


Transistors do not require heating like vacuum tubes, so they are highly efficient, compact in size and durable.


Integrated circuits (ICs) are used in modern PCs, and countless logical operations are performed every second, but transistors are the role of switches to process the operation and control the current It is like existence of invisible rims.