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Question 18.3: If R = 1.5 kΩ and nR = 7.5 kΩ in Fig. 18-12, what is the max...

If R = 1.5 kΩ and nR = 7.5 kΩ in Fig. 18-12, what is the maximum positive
voltage gain? What is the value of the other fixed resistance?

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The value of n is:

n=\frac{7.5 \ k\Omega }{1.5 \ k\Omega } =5

The maximum positive voltage gain is 5. The other fixed resistor has a value of:

\frac{nR}{n-1} =\frac{5(1.5\ k\Omega) }{ 5-1 } =1.875 \ kΩ

With a circuit like this, we have to use a precision resistor to get a nonstandard value like 1.875 kΩ.

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