Determine the values of the overall Problem 11 For the ampli

Determine the values of the overall

Problem 11 For the amplifier shown in Figure 11, determine the values of the overall voltage and power gains. Then determine the efficiency of the amplifier A=1 A Rs Ro 2 in 25mV rms Vo mv ms 8 500Vin +VBB = 15V Figure 11

Solution

Ans) Vin=25 mV *Rin/(Rin+Rs)=25m*(10k/(10k+5k)=16.67 mV (Voltage Division Rule)

Vin=16.67 mV

Vo=500*Vin *RL/(RL+Ro)=500*16.67m*8/(8+2)=6.67 V

Vo=6.67 V

Overall Voltage gain =Vo/Vs=6.67/25m=266.67

Overall Voltage gain Av=266.67

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Power Input Pin=Vs*Is or Vs²/(Rin+Rs)=0.04167 micro Watts

Pin=0.04167 micro Watts

Power output Po=Vo²/RL=5.55 W

Power Gain=Po/Pin=5.55/0.04167 micro=133189344.9

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Total Power supplied Ps=Pin+(VAA*IA +VBB*IB)=Pin+(15*1 +15*0.5)=22.5 W

Efficiency =Po/Ps=5.55/22.5=0.2467=24.67%

So Efficiency=24.67%