In a simplified model for a cascaded amplifier consisting of a first stage with Avoc1 = 200, Ro1 = 500 ohm and a second stage with Avoc2 = 100, Ri2 = 1500 ohm, what is the voltage gain of the first stage (Av1)?

Correct answer: 150

Explanation

When calculating the gain of a stage in a cascade, it is crucial to account for the loading effect of the next stage. The input impedance of the second stage acts as the load resistance for the first stage.

Other questions

Question 1

What is the defining characteristic of an inverting amplifier's voltage gain?

Question 2

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Question 3

In the voltage-amplifier model, what does the output resistance Ro account for?

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Question 5

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Question 6

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Question 7

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Question 8

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Question 9

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Question 10

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Question 11

What is the definition of amplifier efficiency, eta?

Question 12

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Question 13

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Question 14

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Question 15

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Question 16

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Question 17

In an application where an amplifier drives a light-emitting diode (LED) and the light intensity needs to be proportional to the current, what is the desired output impedance for the amplifier?

Question 18

What are the input and output impedance characteristics of an ideal voltage amplifier?

Question 19

What type of ideal amplifier has zero input impedance and infinite output impedance?

Question 20

A transducer's short-circuit current is proportional to liquid level. An amplifier is needed to deliver a voltage signal proportional to this level to a resistive load that varies from 1 k-ohm to 10 k-ohm. What type of ideal amplifier is required?

Question 21

What type of amplifier has constant gain down to zero frequency (DC)?

Question 22

The input voltage to an amplifier is vi(t) = 0.1 cos(2000 pi t - 30 degrees) and the output is vo(t) = 10 cos(2000 pi t + 15 degrees). What is the complex voltage gain, Av?

Question 23

What are the frequencies at which the voltage gain magnitude of an amplifier is 1/sqrt(2) times the midband gain magnitude called?

Question 24

What is the term for an amplifier whose frequency response is deliberately limited to a small bandwidth compared with its center frequency?

Question 25

What type of distortion occurs if the gain of an amplifier has a different magnitude for the various frequency components of an input signal?

Question 26

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Question 27

What condition must be met by an amplifier's phase response to avoid causing phase distortion?

Question 28

What is the approximate relationship between the rise time (tr) and the half-power bandwidth (B) of a wideband amplifier?

Question 29

A radar system needs to distinguish objects that are 10 meters apart, requiring a maximum amplifier rise time of 66.7 ns. Using the rule-of-thumb relationship, what is the minimum required bandwidth for the amplifier?

Question 30

In the pulse response of an AC-coupled amplifier, what is the term for the droop or decay in the flat top of an output pulse?

Question 31

An amplifier is needed to amplify pulses with a duration of 100 microseconds with a sag (tilt) of not more than 1 percent. What is the highest value allowed for the lower half-power frequency (fL) of the amplifier?

Question 32

What is an amplifier's transfer characteristic?

Question 33

If a sinusoidal signal is applied to the input of a nonlinear amplifier, what is the nature of the output signal?

Question 34

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Question 35

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Question 36

What is the output voltage, vo, of an ideal differential amplifier with inputs vi1 and vi2, and a differential gain of Ad?

Question 37

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Question 38

What does the Common-Mode Rejection Ratio (CMRR) of a differential amplifier quantify?

Question 39

A differential amplifier has a differential gain Ad of 50,000. When its inputs are tied together and a 1-V signal is applied, the output is 0.1 V. What is the CMRR in decibels?

Question 40

An electrocardiograph amplifier has a differential gain of 1000. The input is a 1 mV peak differential signal and a 100 V peak common-mode signal. To keep the common-mode output contribution to 1 percent of the differential output, what is the minimum required CMRR in decibels?

Question 41

In the DC model of a real differential amplifier, what are the small DC currents drawn by the internal circuitry through the input terminals called?

Question 42

What is the primary method for mitigating the effects of input bias currents in a differential amplifier circuit?

Question 43

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Question 45

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Question 46

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Question 47

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Question 48

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Question 49

Which amplifier imperfection is primarily responsible for causing 'ringing' in the pulse response?

Question 50

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