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1. Calculate the approximate input impedance of this JFET amplifier circuit:

Explain why it is easier to calculate the Zin of a JFET circuit like this than it is to calculate

the Zin of a similar bipolar transistor amplifier circuit. Also, explain how calculation of this

amplifier's output impedance compares with that of a similar BJT amplifier circuit - same

approach or different approach?

2. Draw the load line and identify the Q-point on that load line for a common-collectoramplifier circuit using this transistor:

3. Draw the load line and identify the Q-point on that load line for a common-emitteramplifier circuit using this transistor:

4. The current gain for the Darlington connection is ________.Which of the following configurations has the lowest output impedance?

A. Fixed-bias

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B. Voltage-divider

C. Emitter-follower

D. None of the above

5. What is the typical value of the current gain of a common-base configuration?6. A common-emitter amplifier has ________ voltage gain, ________ current gain, ________

power gain, and ________ input impedance.

A. high, low, high, low

B. high, high, high, low

7. Refer to this figure. Calculate the value of Rin(tot).

8. What does the negative sign in the voltage gain of the common-emitter fixed-biasconfiguration indicate?

9. The emitter-follower configuration has a ________ impedance at the input and a ________impedance at the output.

10.The ________ configuration is frequently used for impedance matching.11.The total gain of a multistage amplifier is the ________.

A. sum of individual voltage gains

B. sum of dB voltage gains

12.The loaded voltage gain of an amplifier is always more than the no-load level.

A. True B. False

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13.Refer to this figure. You notice while servicing this amplifier that the output signal at Vout isreduced from normal. The problem could be caused by

14.An emitter-follower amplifier has an input impedance of 107 k . The input signal is 12 mV.The approximate output voltage is (common-collector).

15.Refer to this figure. If Vin = 20 mV p-p what is the output voltage?

. 16.Referring to this figure, calculate Zi for yos = 20 S. Assume VGSQ= 2.2V.

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A. 300.2

B. 330.4

C. 340.5

D.

350.0

17. Referring to this figure, calculate Zo if yos = 40 S.

A. 2.92 k

B. 3.20 k

C. 3.25 k

D. 3.75

17.Referring to this figure, calculate Av if rd = 50 k.

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18.19.20.Refer to the given figure. The input impedance of this circuit is

21.

22.An op-amp has an open-loop gain of 75,000 and a cutoff frequency of 100 Hz. At 1 kHz theopen-loop gain is down by

A. 10 dB.

B. 6 dB.

C. 20 dB.

D. 3 dB.

23.Calculate the overall voltage gain of the circuit if R1 = 100 and Rf= 1 k .

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24.25.26.Refer to the given figure. Find the midrange gain of this amplifier.

27.28.A certain op-amp has an open-loop voltage gain of 150,000. What is this gain expressed in

dB?

29.What is the slew rate of an op-amp if the output voltages change from 2 V to 3 V in 0.2 ms?30.Calculate the output voltage if R1 = R2 = R3 = 100 , Rf= 1 k , and V1 = V2 = V3 = 50 mV.

31.

32.Refer to the given figure. The op-amp has a unity-gain bandwidth of 3 MHz. Determine theBW of the circuit.

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33.A practical op-amp has very ________ input impedance, very ________ output impedance,very ________ open-loop voltage gain, and a ________ bandwidth.

34.Calculate the output voltage for this circuit when V1 = 2.5 V and V2 = 2.25 V.

A. 5.25 V

B. 2.5 V

C. 2.25 V

D. 5.25 V

35.Calculate the output voltage if V1 = 0.2 V and V2 = 0 V.

36.

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37.Determine the output voltage when V1 = V2 = 1 V.

38.Calculate the input voltage if the final output is 10.08 V.

39.Calculate the output of the first-stage op-amp when V1 = 25 mV.

40.41.Calculate the output voltage if V1 = V2 = 700 mV.

42.43.This circuit is an example of a(n)________.

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44.45.Determine the value of Rf(assuming that all have the same value).

46. alculate the input voltage for this circuit if Vo = 11 V.

46.Calculate IL for this circuit.

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47.48.Determine the output voltage when V1 = V2 = 1 V.

A. 0 V

B. 2 V

C. 1 V

D. 2 V

49.Only the condition A = ________ must be satisfied for self-sustained oscillations to result.At what phase shift is the magnitude of A at its maximum in the Nyquist plot?

A. 90 B. 180

C. 270 D.

0

What is the minimum frequency at which a crystal will oscillate?

A. seventh harmonic

B. third harmonic

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C. fundamental

D. second harmonic

50.An amplifier with a gain of500 and a feedback of = 0.1 has a gain change of 15% dueto temperature. Calculate the change in gain of the feedback amplifier.

51.Which of the following is required for oscillation?

A. A > 1

B. The phase shift around the feedback network must be 180.

C. Both A > 1 and the phase shift around the feedback network must be 180.

D. None of the above

At what phase shift is the magnitude of A at its minimum in the Nyquist plot?

A. 90 B. 180

C. 270 D. 0(Ans)

What is the total phase shift requirement, around the feedback loop, for a phase-shift oscillator?

A. 90 B. 180

C. 270 D. 360

Answer & Explanation

Answer: Option D

Explanation:

No answer description available for this question.Let us discuss.

At series resonance, the impedance of a crystal is

A. minimum. B. maximum.

C. equal. D. zero.

Answer & Explanation

Answer: Option A

52.

http://www.indiabix.com/electronic-devices/oscillator-circuits/discussion-1649http://www.indiabix.com/electronic-devices/oscillator-circuits/discussion-1649http://www.indiabix.com/electronic-devices/oscillator-circuits/discussion-1649http://www.indiabix.com/electronic-devices/oscillator-circuits/discussion-1649

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