Compare small signal amplifier with power amplifier

Compare small signal amplifier with power amplifier
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1 Answer

Answer :

Parameters
Small signal Amplifiers
Power Amplifiers
Amplification quantity
It increases voltage into high resistance load. Hence small signal amplifiers are also called as voltage amplifiers.
It increases power into low resistance load. Hence these amplifiers are also called as large signal amplifiers.
Current Gain(β)
High(typically 100) 
Low(5 to 20)
Input Resistance(Ri)
Quite low
Very large
Output Impedance(Ro)
High
low
Physical size
Small
Large in size
Coupling
R-C coupling
Transformer coupling
Power output
low
High
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