Configurations of BJT
Why is an ordinary transistor called as bipolar transistor?
An ordinary transistor is also called as bipolar transistor as the basic operations of transistor is carried out by two types of charge carriers (majority charge carriers and minority charge carriers).
Which type of bipolar junction transistor is more effective?
In NPN transistor the conduction of current takes place via electrons while in PNP transistor the conduction takes place by electrons. As electrons are more mobile than holes so, NPN transistor is more effective than PNP transistor.
What is meant by biasing of transistor?
When different terminals of transistor (emitter, base and collector) is connected to an external D.C. source, then it is called as biasing of transistor.
What are the different operating regions of a transistor?
There are four different operating regions of a transistor:
- Active region
- Saturation Region
- Cut – off Region
- Inverted Region
What is the basic application of a transistor?
The basic application is transistor is amplification. Amplification is the process of raising the strength of input signal
Why common-emitter configuration is most widely used in amplifier circuits?
Common-emitter configuration is most widely used in amplifier circuits due to high current and voltage gain. Its ratio of output impedance and input impedance is also high.
Why emitter is always forward-biased, and collector is reverse-biased with respect to base?
Emitter is always forward biased with respect to base as it has to supply majority charge carriers to base, while collector is always reverse biased with respect to base as it has to remove charge carriers from base-collector region.
BJT Configurations
A transistor is also called as bipolar junction transistor or simply BJT. It is called as bipolar as only two types of charge carriers, i.e. majority charge carriers and minority charge carriers are required to perform the operations on transistor. BJT is a current-controlled device as the output voltage, current or power is controlled by the input current in the transistor. As we know, BJT is a three-terminal device , so the three configurations- we will study in this article. The three main configurations are – common emitter , common base and common collector , which has its unique characteristics and applications respectively.
Table of Content
- What is BJT?
- Configurations
- Operating regions of transistor
- Advantages
- Disadvantages
- Applications
- Comparison between CB, CE and CC configurations