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Q1. When negative voltage feedback is applied to an amplifier, its voltage gain ……………….
  1. Is increased
  2. Is reduced
  3. Remains the same
  4. None of the above
Answer : 2
Q2. The value of negative feedback fraction is always …………….
  1. Less than 1
  2. More than 1
  3. Equal to 1
  4. None of the above
Answer : 1
Q3. If the output of an amplifier is 10 V and 100 mV from the output is fed back to the input, then feedback fraction is ………..
  1. 10
  2. 1
  3. 01
  4. 15
Answer : 3
Q4. The gain of an amplifier without feedback is 100 db. If a negative feedback of 3 db is applied, the gain of the amplifier will become …………..
  1. 5 db
  2. 300 db
  3. 103 db
  4. 97 db
Answer : 4
Q5. If the feedback fraction of an amplifier is 0.01, then voltage gain with negative feedback is approximately………..
  1. 500
  2. 100
  3. 1000
  4. 5000
Answer : 2
Q6. A feedback circuit usually employs ……………… network
  1. Resistive
  2. Capacitive
  3. Inductive
  4. None of the above
Answer : 1
Q7. The gain of an amplifier with feedback is known as ………….. gain
  1. Resonant
  2. Open loop
  3. Closed loop
  4. None of the above
Answer : 3
Q8. When voltage feedback (negative) is applied to an amplifier, its input impedance ………….
  1. Is decreased
  2. Is increased
  3. Remains the same
  4. None of the above
Answer : 2
Q9. When current feedback (negative) is applied to an amplifier, its input impedance …………..
  1. Is decreased
  2. Is increased
  3. Remains the same
  4. None of the above
Answer : 1
Q10. Negative feedback is employed in ……………..
  1. Oscillators
  2. Rectifiers
  3. Amplifiers
  4. None of the above
Answer : 3
Q11. Emitter follower is used for …………
  1. Current gain
  2. Impedance matching
  3. Voltage gain
  4. None of the above
Answer : 2
Q12. The voltage gain of an emitter follower is ………..
  1. Much less than 1
  2. Approximately equal to 1
  3. Greater than 1
  4. None of the above
Answer : 2
Q13. When current feedback (negative) is applied to an amplifier, its output impedance ……..
  1. Is increased
  2. Is decreased
  3. Remains the same
  4. None of the above
Answer : 1
Q14. Emitter follower is a ……………….. circuit
  1. Voltage feedback
  2. Current feedback
  3. Both voltage and current feedback
  4. None of the above
Answer : 2
Q15. If voltage feedback (negative) is applied to an amplifier, its output impedance …………..
  1. Remains the same
  2. Is increased
  3. Is decreased
  4. None of the above
Answer : 3
Q16. When a negative voltage feedback is applied to an amplifier, its bandwidth……….
  1. Is increased
  2. Is decreased
  3. Remains the same
  4. Insufficient data
Answer : 1
Q17. An emitter follower has ………… input impedance
  1. Zero
  2. Low
  3. High
  4. None of the above
Answer : 3


Q19. The output impedance of an emitter follower is ……….
  1. High
  2. Very high
  3. Almost zero
  4. Low
Answer : 4
Q1. An oscillator converts ……………..
  1. c. power into d.c. power
  2. c. power into a.c. power
  3. mechanical power into a.c. power
  4. none of the above
Answer : 2
Q2. In an LC transistor oscillator, the active device is ……………
  1. LC tank circuit
  2. Biasing circuit
  3. Transistor
  4. None of the above
Answer : 3
Q3. In an LC circuit, when the capacitor is maximum, the inductor energy is ……….
  1. Minimum
  2. Maximum
  3. Half-way between maximum and minimum
  4. None of the above
Answer : 1
Q4. In an LC oscillator, the frequency of oscillator is ……………. L or C.
  1. Proportional to square of
  2. Directly proportional to
  3. Independent of the values of
  4. Inversely proportional to square root of
Answer : 4
Q5. An oscillator produces……………. oscillations
  1. Damped
  2. Undamped
  3. Modulated
  4. None of the above
Answer : 2
Q6. An oscillator employs ……………… feedback
  1. Positive
  2. Negative
  3. Neither positive nor negative
  4. Data insufficient
Answer : 1
Q7. An LC oscillator cannot be used to produce ……………….. frequencies
  1. High
  2. Audio
  3. Very low
  4. Very high
Answer : 3
Q8. Hartley oscillator is commonly used in ………………
  1. Radio receivers
  2. Radio transmitters
  3. TV receivers
  4. None of the above
Answer : 1
Q9. In a phase shift oscillator, we use …………. RC sections
  1. Two
  2. Three
  3. Four
  4. None of the above
Answer : 2
Q10. In a phase shift oscillator, the frequency determining elements are …………
  1. L and C
  2. R, L and C
  3. R and C
  4. None of the above
Answer : 3
Q11. A Wien bridge oscillator uses ……………. feedback
  1. Only positive
  2. Only negative
  3. Both positive and negative
  4. None of the above
Answer : 3
Q12. The piezoelectric effect in a crystal is ……………
  1. A voltage developed because of mechanical stress
  2. A change in resistance because of temperature
  3. A change in frequency because of temperature
  4. None of the above
Answer : 1
Q13. If the crystal frequency changes with temperature, we say that crystal has ………….. temperature coefficient
  1. Positive
  2. Zero
  3. Negative
  4. None of the above
Answer : 1
Q14. The crystal oscillator frequency is very stable due to ………………. of the crystal
  1. Rigidity
  2. Vibrations
  3. Low Q
  4. High Q
Answer : 4
Q15. The application where one would most likely find a crystal oscillator is ……………..
  1. Radio receiver
  2. Radio transmitter
  3. AF sweep generator
  4. None of the above
Answer : 2
Q16. An oscillator differs from an amplifier because it ………
  1. Has more gain
  2. Requires no input signal
  3. Requires no d.c. supply
  4. Always has the same input
Answer : 2
Q17. One condition for oscillation is ………….
  1. A phase shift around the feedback loop of 180o
  2. A gain around the feedback loop of one-third
  3. A phase shift around the feedback loop of 0o
  4. A gain around the feedback loop of less than 1
Answer : 3
Q18. A second condition for oscillations is ……………….
  1. A gain of 1 around the feedback loop
  2. No gain around the feedback loop
  3. The attention of the feedback circuit must be one-third
  4. The feedback circuit must be capacitive
Answer : 1
Q19. In a certain oscillator Av = 50. The attention of the feedback circuit must be …………
  1. 1
  2. 01
  3. 10
  4. 02
Answer : 4
Q20. For an oscillator to properly start, the gain around the feedback loop must initially be
  1. 1
  2. Greater than 1
  3. Less than 1
  4. Equal to attenuation of feedback circuit
Answer : 2
Q21. In a Wien-bridge oscillator, if the resistances in the positive feedback circuit are decreased, the frequency……….
  1. Remains the same
  2. Decreases
  3. Increases
  4. Insufficient data
Answer : 3
Q22. In Colpitt’s oscillator, feedback is obtained …………….
  1. By magnetic induction
  2. By a tickler coil
  3. From the centre of split capacitors
  4. None of the above
Answer : 3
Q23. The Q of the crystal is of the order of …………
  1. 100
  2. 1000
  3. 50
  4. More than 10,000
Answer : 4
Q24. Quartz crystal is most commonly used in crystal oscillators because ………….
  1. It has superior electrical properties
  2. It is easily available
  3. It is quite inexpensive
  4. None of the above
Answer : 1

Q27. ………….. is a fixed frequency oscillator
  1. Phase-shift oscillator
  2. Hartely-oscillator
  3. Colpitt’s oscillator
  4. Crystal oscillator
Answer : 4
Q28. In an LC oscillator, if the value of L is increased four times, the frequency of oscillations is …………
  1. Increased 2 times
  2. Decreased 4 times
  3. Increased 4 times
  4. Decreased 2 times
Answer : 4
Q29. An important limitation of a crystal oscillator is ……………
  1. Its low output
  2. Its high Q
  3. Less availability of quartz crystal
  4. Its high output
Answer : 1
Q30. The signal generator generally used in the laboratories is ………….. oscillator
  1. Wien-bridge
  2. Hartely
  3. Crystal
  4. Phase shift

Answer : 1

1)   What are the consequences over the non-linear distortion by the inception of negative feedback?

a. Level of non-linear distortion goes on increasing
b. Level of non-linear distortion goes on decreasing
c. Level of non-linear distortion undergoes stability
d. None of the above
Answer  Explanation 
ANSWER: Level of non-linear distortion goes on decreasing
Explanation: 
No explanation is available for this question!
2)   Stability of a transfer gain is generally defined as the reciprocal of _______

a. Resistivity
b. Conductivity
c. Sensitivity
d. Desensitivity
Answer  Explanation 
ANSWER: Sensitivity
Explanation: 
No explanation is available for this question!
3)   What would happen, if the signal Xd  passes through the feedback network?

a. Xd will get multiplied by 'A'
b. Xd will get multiplied by 'β'
c. Xd will get multiplied by '1 – Aβ'
d. Xd will get multiplied by '1 + Aβ'
Answer  Explanation 
ANSWER: Xd will get multiplied by 'β'
Explanation: 
No explanation is available for this question!
4)   After passing through which circuit/network ,does the signal Xd (output signal obtained by taking the difference of two input signals) get multiplied by '-1'?

a. Amplifier circuit
b. Feedback network
c. Mixing network
d. Sampling network
Answer  Explanation 
ANSWER: Mixing network
Explanation: 
No explanation is available for this question!
5)   What would be the computational value of feedback voltage in a negative feedback amplifier with A = 100, β = 0.03 and input signal voltage = 30 mV?

a. 0.03 V
b. 0.06 V
c. 0.09 V
d. 0.15 V
Answer  Explanation 
ANSWER: 0.09 V
Explanation: 
No explanation is available for this question!
6)   Which among the following is an output provided by transresistance amplifier?

a. Output current proportional to signal voltage
b. Output voltage proportional to signal current
c. Output voltage proportional to input voltage
d. Output current proportional to signal current
Answer  Explanation 
ANSWER: Output voltage proportional to signal current
Explanation: 
No explanation is available for this question!
7)   Which among the below specified conditions is responsible to drive a low resistance load by the current amplifier circuit?

a. Rs >> Ri
b. R0 >> RL
c. Rs << Ri
d. R0 << RL
Answer  Explanation 
ANSWER: R0 >> RL
Explanation: 
No explanation is available for this question!
8)   What should be the value of input resistance for an ideal voltage amplifier circuit?

a. Zero
b. Unity
c. Infinity
d. Unpredictable
Answer  Explanation 
ANSWER: Infinity
Explanation: 
No explanation is available for this question!
1. Voltage shunt feedback amplifier forms
a) A negative feedback
b) A positive feedback
c) Both positive and negative
d) None of the mentioned
View Answer
Answer: a
Explanation: A voltage shunt feedback amplifier forms a negative feedback because, any increase in the output signal results in a feedback signal into the inverting input causing a decrease in the output signal.
2. The value of feedback resistor and resistor connected in series with the input signal source are equal to 10kΩ and 3.3kΩ. Calculate the closed loop voltage gain?
a) -6.7
b) -33
c) -13.3
d) -3.33
View Answer
Answer: d
Explanation: Closed loop voltage gain, AF = -RF/R1 = -10kΩ/3.3kΩ = -3.33.
3. Write the formula for closed loop voltage gain of inverting amplifier with feedback using open loop voltage gain and gain of feedback circuit.
a) AF= A/(1+AB)
b) AF= -A/(1+AB)
c) AF= -B/(1+AB)
d) None of the mentioned
View Answer
Answer: c
Explanation: The closed loop voltage gain of the amplifier is AF= -Ak/(1+AB), where k is a voltage attenuation factor. In addition to phase inversion, AF is k times the closed loop gain of the non-inverting amplifier where k<1.
4. Voltage shunt feedback amplifiers are also called as
a) Non-inverting amplifier with feedback
b) Non-inverting amplifier without feedback
c) Inverting amplifier with feedback
d) Inverting amplifier without feedback
View Answer
Answer: c
Explanation: The input and output signal in voltage series feedback amplifier are 180o out of phase (or of opposite polarities). Due to this phase inversion, the configuration is also called as inverting amplifier with feedback.
5. Find the block diagram representation for inverting amplifier with feedback
linear-integrated-circuit-mcqs-voltage-shunt-feedback-amplifier-q5
View Answer
Answer: b
Explanation: The block diagram of non-inverting amplifier is identical to that of inverting amplifier except for the voltage attenuation factor or block. However, the major difference is that a voltage summing junction is being used as a model for what is actually a current summing.
6. The inverting input inverting of the voltage shunt feedback resistor is a commonly named as
a) Terminal ground
b) Virtual ground
c) Virtual input
d) Resistive input
View Answer
Answer: b
Explanation: Ideally, the difference between input voltages is zero. Therefore, the voltage at the inverting terminal is approximately equal to that of non-inverting terminal. In other words, the inverting terminal voltage is approximately at ground potential and it is said to be virtual ground.
7. Compute RIF for an inverting amplifier with feedback, where the value of input resistance of op-amp is 4.7kΩ.
a) 4.7kΩ
b) 9.4kΩ
c) 2.35kΩ
d) Data given is insufficient
View Answer
Answer: a
Explanation: In voltage shunt feedback amplifier, the input resistance with feedback is given as RIF = R1 (ideally).
8. Specification of op-amp 741c is given below:
A=200000; Ri=2MΩ; Ro=75Ω; Supply voltages= ±15v; output voltage swing =±13v; fo=5hz.linear-integrated-circuit-mcqs-voltage-shunt-feedback-amplifier-q8
Compute the value of output resistance, bandwidth and closed loop voltage gain for the circuit shown.
a) ROF=8.6mΩ , fF= 53005hz and AF=-9.36
b) ROF=4.12mΩ , fF= 53005hz and AF=-11.78
c) ROF=7.1mΩ , fF = 53005hz and AF=-16.95
d) ROF=1.9mΩ , fF= 53005hz and AF=-10
View Answer
Answer: c
Explanation: Output resistance of the amplifier, ROF= Ro/(1+AB) =, where B= R1+RF = 330Ω/330Ω+6.2kΩ = 0.053.
=> ROF= ±75/(1+200000*0.053) = 53005hz.
Closed loop voltage gain, AF= -(A*K)/(1+AB), Where k= RF/(R1+F) = 6.2kΩ/(330Ω+6.2kΩ) = 0.949
=> AF = -(200000*0.949)/[1+(200000*0.0535)] = -16.95.
9. What is the break frequency of the op-amp?
a) fo = Unity Gain Bandwidth /closed loop voltage gain
b) fo = Unity Gain Bandwidth / open loop voltage gain
c) fo = Unity Gain Bandwidth /Gain of feedback circuit
d) All of the mentioned
View Answer
Answer: c
Explanation: The mentioned formula is the general break frequency of any operational amplifier.
10. The total voltage offset voltage with feedback (VooT) equation for inverting amplifier is
a) Same as that of non-inverting amplifier
b) k times the non-inverting amplifier, k-> voltage attenuation factor
c) Twice the equation of non-inverting amplifier
d) All of the mentioned
View Answer
Answer: a
Explanation: Voot equation for inverting amplifier is the same as that of the non-inverting amplifier because, when the input signal is reduced to zero, both inverting and non-inverting amplifier results in the same circuit.
11. Which among the following is not a special case of voltage shut feedback amplifier?
a) Voltage follower
b) Current to voltage connector
c) Inverter
d) None of the mentioned
View Answer
Answer: a
Explanation: A voltage follower is a special case of non-inverting amplifier ( or voltage series feedback amplifier) and it has a gain of unity.
12. Compute the output voltage for the given circuit
linear-integrated-circuit-mcqs-voltage-shunt-feedback-amplifier-q12
a) -2.6v
b) -27.8v
c) -26.7v
d) -0.267v
View Answer
Answer: c
Explanation: The given circuit is a current to voltage converter. Since V1 =0v and V1= V2.
=> iin = Vin/R1 = 4/ 1.5kΩ =2.67mA.
The output voltage Vo = -iin*RF = -2.67mA*10kΩ = -26.7v.
13. At what condition an inverting amplifier works as an inverter
linear-integrated-circuit-mcqs-voltage-shunt-feedback-amplifier-q13
a) R1 = RF+ RL
b) RF =( R1*Vin)/RL
c) R1 = RF
d) R1 = Vo/(Vin*RL)
View Answer
Answer: c
Explanation: If R1 = RF, the inverting amplifier will work as an inverter.
14. Determine the output waveform for the given input signal
linear-integrated-circuit-mcqs-voltage-shunt-feedback-amplifier-q14
linear-integrated-circuit-mcqs-voltage-shunt-feedback-amplifier-q14a
View Answer

Answer: a
Explanation: Given, Vin= 3Vpp sinewave at 1khz (Therefore F=1/T=1/ms =1khz)
=> iin= Vin/R1 = 3/ 470=6.4mA
=> Vo=- iin*RF=6.4mA*4.7kΩ = 30 Vpp sinewave at 1khz

1. Find the input and output resistance for the circuit shown.
Specification for 741 op-amp : A=400000 ; Ri = 33MΩ; Ro = 60Ω;
RF = 11kΩ; R1 = 2kΩ; Supply voltage = ± 15v; Maximum output voltage swing = ± 13v.
linear-integrated-circuits-questions-answers-online-quiz-q1
a) RIF = 66MΩ, ROF = 30Ω
b) RIF = 30MΩ, ROF = 6kΩ
c) RIF = 15kΩ, ROF = 50MΩ
d) None of the mentioned
View Answer
Answer: a
Explanation: AF = 1+(RF/R1) = 1+(11kΩ/2kΩ) = 6.5;
B= 1/ AF = 1/6.5 = 0.154;
Input resistance of RIF = R1(1+AB) = 33MΩ[1+(6.5*0.154) ]= 66MΩ;
Output resistance of ROF = Ro/(1+AB) = 60/[1+(6.5*0.154) ]= 29.98 ≅30Ω.
2. The output resistance of the op-amp with feedback is
a) Same as that of the output resistance without feedback
b) Greater than that of the output resistance without feedback
c) Smaller than that of the output resistance without feedback
d) None of the mentioned
View Answer
Answer: c
Explanation: In voltage series feedback amplifier, the output resistance is (1/(1+AB)) times the output resistance of the op-amp. Therefore, the output resistance of the op-amp with feedback is much smaller than the output resistance without feedback.
3. Find the output current in the voltage series feedback amplifier.
a) io ={ [Vo+(A*Vid)]/Ro}
b) io ={ [Vo-(A*Vid)]/Ro}
c) io =(Vo/Ro)*A
d) io =[A*(Vo-Vid)]/Ro
View Answer
Answer: b
Explanation: The output current in voltage series feedback amplifier is given as io ={[Vo-(A*Vid)]/Ro}.
4. Find the unity gain bandwidth for voltage series feedback amplifier?
a) UBG = Afo
b) UBG = AfF
c) UBG = Afo fF
d) UBG = AFfo
View Answer
Answer: a
Explanation: The unity gain bandwidth is given as product of open loop voltage gain and break frequency of an op-amp.
5. The bandwidth of a non-inverting amplifier with feedback is equal to
a) fo(AB)
b) fo(AB-1)
c) fo(1+AB)
d) fo(1-AB)
View Answer
Answer: c
Explanation: The bandwidth of the non-inverting amplifier with feedback is equal to its bandwidth without feedback times (1+AB). i.e. fF=fo(1+AB).
6. How are the saturation voltage specified on the manufacture’s datasheet?
a) Negative voltage
b) Output voltage swing
c) Supply voltage
d) None of the mentioned
View Answer
Answer: b
Explanation: In an open loop op-amp, the total output offset voltage (i.e. output voltage swing) is equal to either the positive or negative saturation voltage.
7. What is the formula for total output offset voltage with feedback?
a) VooT = ± Vo/(1+AB)
b) VooT = ± Vsat*(1+AB)
c) VooT = ± Vsat/(1+AB)
d) VooT = ± Vo*(1+AB)
View Answer
Answer: c
Explanation: The total output offset voltage with feedback = (Total output offset voltage witput feedback) / (1+AB). i.e. VooT = ± Vsat/(1+AB).
8. Which of the following has the same characteristic as that of non-inverting amplifier with feedback?
a) Perfect feedback amplifier
b) Voltage follower
c) Perfect voltage amplifier
d) All of the mentioned
View Answer
Answer: c
Explanation: A perfect voltage amplifier has very high input resistance, very low output resistance, stable voltage gain, large bandwidth and very little output offset voltage.
From the analysis of the characteristic of non-inverting amplifier with feedback, it is clear that it exhibits the characteristics of a perfect voltage amplifier.
9. What is the gain of voltage follower?
a) Gain > ∞
b) Gain –>1
c) Gain <1
d) Gain –>∞
View Answer
Answer: b
Explanation: Voltage follower is non-inverting amplifier configured for unity gain. Such that the output voltage is equal to and in phase with the input.
10. Which is preferred to attain higher input resistance and the output amplitude equal to input?
a) Voltage follower
b) Voltage series feedback amplifier
c) Voltage shunt feedback amplifier
d) Inverter
View Answer
Answer: a
Explanation: In the voltage follower the output follow the input due to unity gain. Therefore, it is attained to get higher input resistance and output amplitude equal to input.
11. Find the input and output voltage in voltage follower circuit?
a) Vin=2v and Vout = 3v
b) Vin=10v and Vout = 11v
c) Vin=9v and Vout = 9v
d) Vin=4v and Vout = 7v
View Answer
Answer: c
Explanation: Voltage follower has input voltage equal to output voltage. The closed loop voltage gain is equal to one. For example, take the input and output voltage to be 2v, then AF = Vout/Vin = 2v/2v = 1.
12. Voltage follower is also called as
a) None of the mentioned
b) Non-inverting amplifier
c) Inverting amplifier
d) Normal buffer
View Answer
Answer: b
Explanation: The voltage follower is also called as a non-inverting buffer because, when placed between two networks, it removes the loading on the first network.
13. Find the bandwidth and total output offset voltage of a voltage follower? The following are the specifications for the op-amp 741: A=200000, fo =5hz and supply voltage =±15v.
linear-integrated-circuits-questions-answers-online-quiz-q13
a) fF = 1000hz, VooT = ± 7.5µv.
b) fF = 100khz, VooT = ± 7.5µv.
c) fF = 10khz, VooT = ±7.5µv.
d) fF = 1000khz, VooT = ± 7.5µv.
View Answer
Answer: d
Explanation: Bandwidth fF =A* fF = 200000*5= 1Mhz.
Total output offset voltage, VooT= ±Vsat/A= ±15/200000 =± 7.5µv

1. Specify the voltage gain of non-inverting amplifier with feedback amplifier with and without feedback?
a) A= Vo/Vid, AF = Vf/Vo
b) A= Vf/Vid, AF= Vo/Vf
c) A= Vo/Vid, AF= Voin
d) A= Vf/Vid, AF = Vf/Vin
View Answer
Answer: c
Explanation: The voltage gain of op-amp with feedback is the open loop voltage gain, A=Vo/Vid. The voltage gain of op-amp without feedback is the closed loop voltage gain, AF = Vo/Vin.
2. If the feedback voltage and the output voltage are given as 10v and 4v. Find the gain of the feedback circuit in voltage-series feedback amplifier?
a) 2.5v
b) 40v
c) 3v
d) 6.2v
View Answer
Answer: a
Explanation: Gain of feedback, B = Vf /Vo = 10v/4v = 2.5v.
3. How is the difference voltage calculated in closed loop non-inverting amplifier?
a) Vid= Vo – Vf
b) Vid= Vin – Vf
c) Vid= Vo – Vin
d) Vid= Vf – Vin
View Answer
Answer: b
Explanation: Although, the input is given to the non-inverting terminal of op-amp, the difference voltage is equal to the input voltage minus feedback voltage is Vid= Vin – Vf.
4. Why the feedback circuit is said to be negative for voltage series feedback amplifier?
a) Feedback voltage is 180o out of phase with respect to input voltage
b) Input voltage is 180o out of phase with respect to feedback voltage
c) Feedback voltage is in same phase with respect to input voltage
d) Input voltage is in same phase with respect to feedback voltage
View Answer
Answer: a
Explanation: Voltage series feedback amplifier have the difference voltage, Vid = Vin-Vf. Therefore, the feedback voltage always opposes the input voltage and is out of phase by 180o with respect to input voltage. Hence, the feedback is said to be negative.
5. Determine the closed loop voltage gain from the given circuit. (Where gain of op-amp= 105).
linear-integrated-circuit-mcqs-voltage-series-feedback-amplifier-1-q5
a) 1090.9
b) 9821.43
c) 9166.66
d) 10000
View Answer
Answer: b
Explanation: The closed loop voltage gain , AF = {[A*(R4+R5)]/[(RF+R1+(A*R1)]} = [105*(10kΩ+1kΩ)]/[1kΩ+10kΩ+(105*1kΩ)] =11×108/112000
=> AF = 9821.43.
6. Express closed loop voltage gain (AF) in terms of open loop gain (A) and feedback circuit gain (B)?
a) AF = A/AB
b) AF = 1+ (A/AB)
c) AF = A/(1+AB)
d) AF = AB/(1+A)
View Answer
Answer: c
Explanation: The closed loop voltage gain in terms of open loop gain and feedback circuit gain is expressed as AF = A/(1+AB).
7. Which factor determines the gain of the voltage series feedback amplifier?
a) Open loop voltage gain
b) Feedback voltage
c) Ratio of two resistors
d) Gain of feedback circuit
View Answer
Answer: c
Explanation: In setting the gain of the voltage series feedback amplifier, the ratio of two resistors is important and not the absolute value of these resistors. For example: If a gain of 11 is desired, we choose R1=1kΩ and R1=10kΩ or R1=100Ω and RF= 1kΩ.
8. For the feedback circuit of voltage series feedback amplifier, find the feedback voltage for the specifications: R1=1kΩ, RF = 10kΩ and Vo= 25v.
a) 12.5v
b) 22v
c) 0.9v
d) 2.3v
View Answer
Answer: d
Explanation:linear-integrated-circuit-mcqs-voltage-series-feedback-amplifier-1-q8
The feedback voltage, Vf = (R1*Vo)/(R1+RF) = (1kΩ*25v)/(1kΩ+10kΩ) = 2.272v ≅ 2.3v.
9. What must be the value of external components used in voltage series feedback amplifier?
a) Less than 1MΩ
b) Less than 10MΩ
c) Less than 100MΩ
d) Less than 0.1MΩ
View Answer
Answer: a
Explanation: All external components value should be less than 1MΩ. So, that they do not adversely affect the internal circuitry of the op-amp.
10. Find the block diagram representation of non-inverting amplifier with feedback?
linear-integrated-circuit-mcqs-voltage-series-feedback-amplifier-1-q10
View Answer
Answer: a
Explanation: The mentioned block diagram is the standard form for representing a system with feedback.
11. Define the input resistance with feedback for voltage series feedback amplifier?
a) RIF = (1-AB)
b) RIF = (AB-1)
c) RIF = (1+AB)
d) None of the mentioned
View Answer
Answer: c
Explanation: In feedback amplifier, the input resistance of the op-amp with feedback is (1+AB) times that of without feedback.
12. When the non-inverting input terminal of an op-amp is equal to that of the inverting input terminal (ideally)
a) a–>∞
b) Vid ≅ 0
c) AF = 1+( RF / R1)
d) All of the mentioned
View Answer
Answer: d
Explanation: When the input at both the terminal are equal, the difference input voltage, Vid=Vin1– Vin2.
=> Vid≅0 (∵Vin1= Vin2)
The open loop voltage gain, A= Vo/ Vid = Vo/0 = ∞ and
the closed loop voltage gain, AF= Vo/ Vin = 1+ (RF/ R1)

1. A feedback amplifier is also called as
a) Open loop amplifier
b) Closed loop amplifier
c) Feedback network amplifier
d) Looped network amplifier
View Answer
Answer: b
Explanation: A feedback amplifier is sometimes referred as a closed loop amplifier because the feedback forms a closed loop between input and the output.
2. How many types of configuration are available for feedback amplifier?
a) Six
b) Four
c) Two
d) Eight
View Answer
Answer: b
Explanation: There are four type of configuration are available. They are voltage series feedback, voltage shunt feedback, Current series feedback and Current shunt feedback.
36. 
One condition for positive feedback is that the phase shift around the feedback loop must be ________°.
A.0
B.90
C.180
D.45
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
37. 
At what phase shift is the magnitude of A at its minimum in the Nyquist plot?
A.90º
B.180º
C.270º
D.0º
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
38. 
Determine the output impedance with feedback for a voltage-series feedback having A = –100, R1 = 15 k, Ro = 20 k, and a feedback of  = –0.25.
A.0.2 k
B.392.16 
C.1.82 k
D.769.23 
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
39. 
Determine the voltage gain with feedback for a voltage-series feedback having A = –100, R1 = 15 k, Ro = 20 k, and a feedback of  = –0.25.
A.3.85
B.–3.85
C.–9.09
D.9.09
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
40. 
Calculate the resonant frequency of this Wien bridge oscillator if R1 = 25 k, R2 = 40 k, C1 = 0.001 F, and C2 = 0.002 F.
A.1560.3 Hz
B.1779.4 Hz
C.3120.7 Hz
D.3558.8 Hz
Answer: Option D

41. 
The Nyquist plot combines the two Bode plots of gain versus frequency and phase shift versus frequency on a single plot.
A.True
B.False
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
42. 
Calculate the resonant frequency of this oscillator.
A.1560.34 Hz
B.3120.70 Hz
C.4681.07 Hz
D.6241.37 Hz
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
43. 
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: Option D
Explanation:
No answer description available for this question. Let us discuss.
44. 
An input signal is needed for an oscillator to start.
A.True
B.False
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
45. 
Referring to this figure, calculate the amplification gain with feedback for the following circuit values: R1 = 80 k, R2= 20 k, Ro = 10 k, RD = 61 k, and gm = 4000 μS.
A.–4.36
B.–4.25
C.–6.35
D.–20.85
Answer: Option A
46. 
The lead-lag circuit in the Wien-bridge oscillator has a resonant frequency at which the attenuation is
A.1/2.
B.1/4.
C.1/3.
D.1/5.
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
47. 
The start-up gain of an oscillator must be ________ one.
A.equal to
B.less than
C.greater than
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
48. 
Refer to this figure. What is the duty cycle, if any?
A.16.3%
B.54.5%
C.86.9%
D.none
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
49. 
In the IC phase-shift oscillator, what should the ratio of feedback resistor Rf to R1 be?
A.Zero
B.Greater than –29
C.Less than 29
D.Any value
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
50. 
At series resonance, the impedance of a crystal is
A.minimum.
B.maximum.
C.equal.
D.zero.
Answer: Option A
51. 
For frequencies up to 1 MHz, the ________ is the most widely used type of sinusoidal RC oscillator.
A.Wien-bridge
B.phase-shift
C.twin-T
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
52. 
The twin-T oscillator produces a ________ response.
A.low-pass
B.high-pass
C.band-pass
D.band-stop
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
53. 
What is the typical value of quality factor for crystal oscillators?
A.20,000
B.1000
C.100
D.10
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
54. 
Which of the following improvements is (are) a result of the negative feedback in a circuit?
A.Higher input impedance
B.Better stabilized voltage gain
C.Improved frequency response
D.All of the above
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
55. 
Refer to the given figure. This circuit is known as
A.a Clapp oscillator.
B.an Armstrong oscillator.
C.a Colpitts oscillator.
D.a Hartley oscillator.
Answer: Option A
56. 
In the Wien bridge oscillator, which of the following is (are) frequency-determining components?
A.R1 and R2
B.C1 and C2
C.R1, R2, C1, and C2
D.None of the above
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
57. 
Determine the input impedance with feedback for a voltage-series feedback having A = –100, R1 = 15 k, Ro = 20 k, and a feedback of  = –0.25.
A.110 k
B.290 k
C.390 k
D.510 k
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
58. 
A certain oscillator has a tap on the inductor in the tank circuit. This oscillator is probably
A.a Colpitts oscillator.
B.a Clapp oscillator.
C.a crystal oscillator.
D.a Hartley oscillator.
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
59. 
At parallel resonance, the impedance of a crystal is
A.minimum.
B.maximum.
C.equal.
D.zero.
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
60. 
Refer to this figure. Assuming it is configured as an oscillator and if you desired to reduce the duty to less than 50%, the following circuit change would need to be made.
A.Reduce the size of R1.
B.Reduce the size of R2.
C.Increase the size of R1.
D.Connect a diode in parallel with R1.
Answer: Option D
61. 
Calculate the fr of a lead-lag network if R1 = R2 = 6.8 k, and C1 = C2 = 0.05 F.
A.468 Hz
B.4.68 kHz
C.46.8 kHz
D.468 kHz
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
62. 
Which of the following is (are) feedback?
A.Voltage-series
B.Voltage-shunt
C.Current-series
D.All of the above
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
63. 
What is the relationship between the series and parallel resonant frequencies of a quartz crystal?
A.They are equal.
B.Parallel resonant frequency is approximately 1 kHz higher than series resonant frequency.
C.Series resonant frequency is approximately 1 kHz higher than parallel resonant frequency.
D.none of the above
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
64. 
An op-amp integrator has a square-wave input. The output should be
A.a sine wave.
B.a triangle wave.
C.a square wave.
D.pure dc.
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
65. 
The frequency distortion arising because of varying amplifier gain with frequency is considerably reduced in a negative-voltage feedback amplifier circuit.
A.True
B.False
Answer: Option A
3. Which of the following is not a feedback configuration?
a) Current-series feedback
b) Voltage-shunt feedback
c) Current-Voltage feedback
c) Current-Shunt feedback
View Answer
Answer: c
Explanation: In a feedback amplifier, either current or voltage can be fed back to the input, but both current and voltage cannot be feedback simultaneously.
4. When load current flows into the feedback circuit, the configuration is said to be
a) Current-shunt feedback
b) Voltage-shunt feedback
c) Voltage-series feedback
d) All of the mentioned
View Answer
Answer: b
Explanation: In current-series and current-shunt feedback circuit, the load current flows into the feedback circuit.
5. Find the voltage-series feedback amplifier from the given diagram?
linear-integrated-circuit-mcqs-block-diagram-representation-feedback-configurations-q5
View Answer
Answer: a
Explanation: The mentioned diagram is the voltage-series feedback amplifier because the voltage across load resistor is the input voltage to the feedback circuit.
6. On what criteria does the feedback amplifier are classified?
a) Signal fed back to input
b) Signal applied to input
c) Signal fed back to output
d) None of the mentioned
View Answer
Answer: d
Explanation: The feedback amplifiers are classified according to whether the voltage or current is fed back to the input in series or in parallel.
3. 
At what phase shift is the magnitude of A at its maximum in the Nyquist plot?
A.90º
B.180º
C.270º
D.0º
Answer: Option B

4. 
Which of the following improvements is (are) a result of the negative feedback in a circuit?
A.Lower output impedance
B.Reduced noise
C.More linear operation
D.All of the above
Answer: Option D

5. 
This circuit is a ________ oscillator.
A.phase-shift
B.Wien bridge
C.Colpitts
D.Hartley
Answer: Option A

10. 
The attenuation of the three-section RC feedback phase-shift oscillator is
A.1/9.
B.1/30.
C.1/3.
D.1/29.
Answer: Option D
11. 
Referring to this figure, calculate the voltage gain without feedback for the following circuit values: RD = 4 k, RS = 1 k, RF = 15 k, and gm = 5000 μS.
A.–20.0
B.–21.5
C.–23.5
D.–25.5
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
12. 
For a phase-shift oscillator, the gain of the amplifier stage must be greater than ________.
A.19
B.29
C.30
D.1
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
13. 
Which of the following is (are) the determining factor(s) of the stability of a feedback amplifier?
A.A
B.Phase shift between input and output signals
C.Both A and the phase shift between input and output signals
D.None of the above
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
14. 
What is the minimum frequency at which a crystal will oscillate?
A.seventh harmonic
B.third harmonic
C.fundamental
D.second harmonic
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
15. 
An amplifier with a gain of –500 and a feedback of  = –0.1 has a gain change of 15% due to temperature. Calculate the change in gain of the feedback amplifier.
A.0.2%
B.0.3%
C.0.4%
D.0.5%
Answer: Option B
7. The closed loop voltage gain is reciprocal of
a) Voltage gain of op-amp
b) Gain of the feedback circuit
c) Open loop voltage gain
d) None of the mentioned
View Answer
Answer: b
Explanation: Comparing the equation of closed loop voltage gain (AF) and the gain of the feedback circuit (B). AF is reciprocal of B
=> AF = 1+( RF/ R1) ; B= R1/( R1+ RF)
=> B = 1+( R1/ RF)
Therefore, AF = 1/B.
2. 
Only the condition A = ________ must be satisfied for self-sustained oscillations to result.
A.0
B.–1
C.1
D.None of the above
Answer: Option C

6. 
Refer to the given figure. The resonant frequency is controlled by
A.C3 and L1.
B.C2, C4, C5, and L1.
C.C3, C4, C5, and L1.
D.C3, C4, C5, and L2.
Answer: Option C
8. 
The feedback signal in a(n) ________ oscillator is derived from an inductive voltage divider in the LC circuit.
A.Hartley
B.Armstrong
C.Colpitts
Answer: Option A
9. 
Given gm = 5000 S, rd = 40 k, R = 10 k, and A = 35. Determine the value of RD for oscillator operation at 1 kHz.
A.8.05 k
B.8.48 k
C.10.8 k
D.12.3 k
Answer: Option B
21. 
Refer to this figure. Calculate the resonant frequency.
A.1.126 kHz
B.6.17 kHz
C.23.9 MHz
D.14.1 MHz
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
22. 
Which of the following is required for oscillation?
A.A > 1
B.The phase shift around the feedback network must be 180º.
C.Both A > 1 and the phase shift around the feedback network must be 180º.
D.None of the above
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
23. 
A circuit that can change the frequency of oscillation with an application of a dc voltage is sometimes called
A.a voltage-controlled oscillator.
B.a crystal oscillator.
C.a Hartley oscillator.
D.an astable multivibrator.
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
24. 
In order to start up, a feedback oscillator requires
A.negative feedback less than 1.
B.positive feedback greater than 1.
C.unity feedback equal to 1.
D.no feedback.
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
26. 
Refer to this figure. If C1 increases in value, the resonant frequency will
A.increase.
B.decrease.
C.remain the same.
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
27. 
What is the ratio of the input impedance with series feedback to that without feedback?
A.1 + A
B.A
C.
D.1
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
28. 
The amplifier is unstable if the Nyquist curve plotted encloses (encircles) the –1 point, and it is stable otherwise.
A.True
B.False
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
29. 
Which of the following oscillators is (are) tuned oscillators?
A.Colpitts
B.Hartley
C.Crystal
D.All of the above
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
30. 
What is the ratio of the output impedance with series feedback to that without feedback?
A.1
B.1 + A
C.A
D.A
Answer: Option B
31. 
Refer to the given figure. This circuit is known as
A.a Clapp oscillator.
B.an Armstrong oscillator.
C.a Colpitts oscillator.
D.a Hartley oscillator.
Answer: Option D
Explanation:
No answer description available for this question. Let us discuss.
32. 
Refer to the given figure. This circuit is known as
A.a Clapp oscillator.
B.an Armstrong oscillator.
C.a Colpitts oscillator.
D.a Hartley oscillator.
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
33. 
Refer to this figure. Determine the frequency of oscillation, if any.
A.131 Hz
B.262 Hz
C.2.62 kHz
D.none
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
34. 
Referring to this figure, calculate the amplification gain where the op-amp gain (A) is 200,000, R1 = 1.5 k, and R2= 400 .
A.4.25
B.4.50
C.4.75
D.5.00
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
35. 
Referring to this figure, calculate the voltage gain with feedback Avf.
A.–4.85
B.–4.20
C.–4.17
D.–4.00
Answer: Option C
25. 
This circuit is a ________ oscillator.
A.phase-shift
B.Wien bridge
C.Colpitts
D.Hartley
Answer: Option C

7. 
Refer to this figure. Determine the resonant frequency.
A.123.4 kHz
B.61.7 kHz
C.45.94 kHz
D.23.1 kHz
Answer: Option C
8. Select the specifications that implies the inverting amplifier?
a) V1 = -3v, V2 = -4v
b) V1 = -2v, V2 = 3v
c) V1 = 5v, V 2 = 15v
d) V1 = 0v, V2 = 5v
View Answer
Answer: d
Explanation: In inverting amplifier, the input is applied to the inverting terminal and the non-inverting terminal is grounded. So,the input applied to inverting amplifier can be V1 = 0v, V2= 5v

1. 
Calculate the value of C1 = C2 for the Wien bridge oscillator to operate at a frequency of 20 kHz. Assume R1 = R2 = 50 k and R3 = 3R4 = 600?
A.1.59 pF
B.15.9 pF
C.159 pF
D.1.59 nF
Answer: Option C
16. 
The feedback signal in a(n) ________ oscillator is derived from a capacitive voltage divider in the LC circuit.
A.Hartley
B.Armstrong
C.Colpitts
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
17. 
Refer to this figure. This circuit is
A.a sine-wave oscillator.
B.a monostable multivibrator.
C.an astable multivibrator.
D.a VCO.
Answer: Option C
Explanation:
No answer description available for this question. Let us discuss.
18. 
This circuit is a ________ oscillator.
A.phase-shift
B.Wien bridge
C.Colpitts
D.Hartley
Answer: Option B
Explanation:
No answer description available for this question. Let us discuss.
19. 
Sinusoidal oscillators operate with ________ feedback.
A.positive
B.negative
Answer: Option A
Explanation:
No answer description available for this question. Let us discuss.
20. 
Referring to this figure, calculate the voltage gain with the feedback for the following circuit values: RD = 4 k, RS = 1 k, RF = 15 k, and gm = 5000 μS.
A.–11.2
B.–8.57
C.–6.75
D.–3.25
Answer: Option B
MCQ. Maximum efficiency produced by Class B amplifier is
  1. 50%
  2. 60%
  3. 79%
  4. 84%
 C
Class C Amplifiers Quiz
MCQ. Power dissipation of Class C amplifiers is
  1. high
  2. low
  3. very high
  4. very low
 B
Transistor AC models Quiz
MCQ. H parameter configuration of common - emitter is
  1. hie
  2. hfe
  3. hge
  4. Both a and b
 D
N-type and P-type semiconductors Quiz
MCQ. Pentavalent atoms are atoms known as
  1. accepters
  2. donors
  3. sacrificers
  4. selfish
 B


Zener diode application Quiz
MCQ. Maximum zener impedance is denoted by symbol of
  1. Zz
  2. Zx
  3. Zy
  4. Z
 
9)   Which among the following parameter/s increase/s due to positive feedback?

A. Input voltage
B. Output Voltage
C. Noise
D. Voltage Gain

a. A & B
b. Only C
c. B & D
d. A, B, C & D
Answer  Explanation 
ANSWER: A, B, C & D