Draw and explain self-basing of a transistor.

1 Answer

Answer :

Transistor Biasing is the process of setting a transistors DC operating voltage or current conditions to the correct level so that any AC input signal can be amplified correctly by the transistor.

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ExplanationIt is required to find the value of RB so that required collector current flows in the zero signal conditions. Let IC be the required zero signal collector current. 

∴ IB =IC*β 

Considering the input closed circuit and applying Kirchhoff 's voltage law, 

VCC = IB RB + VBE 

IB* RB = VCC − VBE 

∴ IB = (VCC –VBE) / RB 

As VCC and IB are known and VBE can be seen from the transistor manual, therefore, value of RB can be readily found VBE is generally quite small as compared to VCC, the former can be neglected 

Applying KVL to o/p loop , Collector-emitter voltage, VCE = VCC − IC RC

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