Characteristics of BJT in CE combination

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Purpose:-

To study and plot the BJT characteristics in Common Emitter configuration.

Theory: -



A BJT is three terminal two junction semiconductor device in which the conduction is due to both the charge carrier. Hence, it is a bipolar device. BJT is classified into two types NPN or PNP. A NPN transistor consists of two N types in between which a layer of P is sand witched. The transistor consists of three terminal emitter, collector base. The emitter layer is the source of charge carrier and it is heavily doped with a moderate cross sectional area.   The collector collects the charge carrier and hence moderate doping and large cross section area. The base region acts as path for the movement of the charge carrier. In order to reduce the recombination of holes and electrons the base region is lightly doped and is of low cross sectional are. BJT is operated in the active mode i.e emitter-base junction is forward biased and collector-base junction is reverse biased.

It's Current gain is β: -

The ratio of collector current to emitter current at constant collector emitter voltage. Its value is less than 1.


Procedure:-

Output characteristics:-

1.Connects the circuit as per the circuit diagram.

2.Set I

3.Plot the graph: V

i)Tabular column 

i)Nature of graph


Transfer characteristics:-

ii) Tabular column


ii)Nature of graph 





1.Set V

2.Vary IB

3.Note down IC

Results:-

The transistor characteristics of common emitter (CE) configuration were plotted & determine the value of current gain β= ____

 


 



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