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Question 8.2: Repeat Ex. 8.1 if the amplifier's output noise power spectra......

Repeat Ex. 8.1 if the amplifier’s output noise power spectral density starts to roll off at 1 MHz as seen in Fig. 8.10.

8.10
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We begin by using Eq. (8.16) directly, that is,

V_{o n o i s e,R M S}=\sqrt{N E B}\,\cdot\,\sqrt{V_{L F,n o i s e}^{2}}            (8.16)

V_{o n o i s e,R M S}=\sqrt{f_{3d B}\cdot\frac{\pi}{2}}~\cdot~\sqrt{V_{L F,n o i s e}^{2}}          (8.17)

which evaluates to 12.5 μV. The gain of the amplifier is 100 so V_{inoise,RMS}=125\ nV.

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