this presentation is about transistor and its type, how transistor works, what is the importance of the transistor in our world and what was use before transistor.

1. Transistor
Ghufran Ataie
Aria University

2. Key Study
• What is Transistor?
• The World Before Transistor
• What Transistors Do?
• Type of Transistors
• BJT
• FET
• How Transistor Works
• Transistor as a Switch
• Transistor as Amplifier

3. What is Transistor
• A Transistor is a semiconductor device used to amplify or switch
electronic signals and electrical power.
• A Transistor is composed of with least three terminal of connection.
• One pair is used to apply current or voltage
• Another pair is used to controlled (output) power
• The Output Power can be higher than controlled input
• The transistors are made of Silicon which is semiconductor

4. The World Before Transistors
• Earlier computers and machines uses
Vacuum Tube to control current flow
• The problem of using vacuum tube is big
size
• Another problem was that Vacuum Tube
becomes warm and damaged
• Uses too much energy
• Specific operators was responsible to
change the Tubes

5. What Transistor Do
• Amplify the law signal to high signal
• Convert DC to AC
• Regulate the Voltage
• Switching On or Off the Circuits
• Convert Radio Signal to Audio (Wave Form) Signal
• Convert Audio Signal to Radio Signal

6. Type of Transistor
• There are two major type of Transistors
• Bipolar Junction Transistor (BJT)
• Field Effect Transistor (FET)

7. Bipolar Junction Transistor (BJT)
• Mostly uses in low current applications
• Bipolar transistors are so named because they
conduct by using both majority and
minority carriers
• It is a combination of two junction diodes
• There are two types of (BJT) known as NPN
PNP
• Same in function both provides switching or
amplification

8. Bipolar PNP and NPN
• E = Emitter
• C = Collector
• B = Base

9. Field Effect Transistor (FET)
• Also called unipolar transistor
• Mostly use in high voltage
• Most commonly used in analog signals
• A FET has Gate, Source and Drain
• The Operation in FET is depended on Voltage, While the operation in
BJT is depended on current at the base
• One of the most uses of FET type is MOSFET

10. How Transistor Works
• In a MOSFET transistor there are three terminals
called as follow
• D = Drain, G = Gate, S = Source
• D - is use for loading voltage as a source
• G - is use for sending digital signals in form of 0
and 1 to connect the switch between D and C, if
the signal is 1 then the switch will be up if the
signal is 0 then it will cut the power
• S - is used the loaded voltage to power up
• The graphic example is in next slide

11. How Transistor Works

12. Transistor as a switch
• Transistors are commonly used
in digital circuits as electronic
switches which can be either in an
"on" or "off" state

13. Transistor as an Amplifier
The transistor's current amplification
combined with the properties of the
circuit means that small swings in Vin
produce large changes in Vout.
From mobile phones to televisions, vast
numbers of products include amplifiers
for sound reproduction, radio
transmission, and signal processing
The Main Example is a loud speaker

14. Thank You