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Question 7.4: A certain amplifier has an open-loop midrange gain of 150,00...

A certain amplifier has an open-loop midrange gain of 150,000 and an open-loop 3 dB bandwidth of 200 Hz. The attenuation of the feedback loop is 0.002. What is the closed-loop bandwidth?

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B W_{c l}=B W_{o l}\left(1+B A_{o l(m i d)}\right)=200 \mathrm{~Hz}[1+(0.002)(150,000)]=\mathbf{6 0 . 2} ~\mathbf{k H z}

P R A C T I C E EXERCISE

If A_{o l(\text { mid })}=200,000 \text { and } B=0.05, what is the closed loop bandwidth?

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