Sub: AEC ( analog electronic circuits)
Year: II B.Tech II- Sem EEE
UNIT – I
SINGLE STAGE AMPLIFIERS
MULTIPLE CHOICE
1. Improper biasing of transistor circuit reads to [ ]
a) distortion in output signal b) faulty location of load line
c) heavy loading of terminal d) none
2. The by pass capacitor across the emitter resistance [ ]
a) increases the emitter current b) increases the output signal
c) both a and b d) none
3. The maximum peak –to-peak output voltage swing is obtained when a
point is located [ ]
a) near saturation point b) towards the cut off point
c) at the centre of load line d) none
4. Darlington pair is used for [ ]
a) low distortion b) high frequency range
c) high power gain d) high current gain
5. The upper cut off 3 dB frequency in a CE is given in terms of h-parameters as …. [ ]
a) 
b) 
c) 
d) 
b) c) d) 6. Which of the following method of biasing provides the best operating point stability[ ] a) two battery bias b) fixed bias c) self bias d) none
7. The approx value of input impedance of a CE amplifier with 
is given by [ ]
is given by [ ] a) 
b) 
b) c) 
d) None
d) None8. Stability factor S in fixed bias CE amplifier is given by [ ]
a) 
b) 
c) 
d) 
b) c) d) 9. A BJT having 
is biased at a dc collector current of 1 MA, the value of
is biased at a dc collector current of 1 MA, the value of 
respectively. [ ] a) 40 m A/V, 2K
b) 45 m A/V, 2.5 K
b) 45 m A/V, 2.5 K c) 4 m A/V, 2.5 K d) 35 m A/V, 2K
d) 35 m A/V, 2K10. For the BJT operated at 
the value of 
and 
respectively
the value of and respectively if 
, 
at 50 m H Z is [ ]
, at 50 m H Z is [ ] a) 500 KHZ, 10.7 PF b) 500 HZ, 10.7 PF
c) 500 mH Z, 10.7 
F d) 500 K H Z, 10.7 F
F d) 500 K H Z, 10.7 FFILL IN THE BLANKS
11. The potential divider bias is used in amplifiers to make the
__________ almost independent of B
12. The h-parameter equivalent of a junction transistor is valid for ___________
13. Condition for ON of BJT is ________
14. The emitter resistor in an stabilized bias circuit appears to be______ in the base circuit.
15. Laser the no signal conduction of an amplifier ________ its efficiency.
TRUE OR FALSE
16. Hybrid pie model cannot be used for analysis of transistors at high frequencie [ ]
17. lower cutoff & higher cut off frequency of an rc coupled amplifier
are similar to of CE stage [ ]
18. at frequency below lower cut off frequency in CE amplifier coupling capacitor at the base of the amplifier form an LPF with emitter resistance [ ]
19. frequency distortion in an amplifier is mainly due to the reactive component circuit [ ]
20. amplitude distortion is also referred to as non-linear distortion [ ]
Answers
1. | A | 6. | C | 11. | operating point | 16. | F |
2. | B | 7. | B | 12. | low frequency small signal operation. | 17. | T |
3. | C | 8. | B | 13. |  | 18. | F |
4. | D | 9. | C | 14. | Smaller | 19. | T |
5. | A | 10. | B | 15. | Higher | 20. | T |
UNIT – II
BJT &FET FREQUENCY RESPONSE
MULTIPLE CHOICE
1. Which of the following is not time varying quantity [ ]
a) 
b) 
c) 
d) None
b) c) d) None2. The value of Tran conductance of a bipolar transistor for a collector current
of 1.5mA is [ ]
a) 
b) 
c) 
d) None
b) c) d) None3. The capacitance 
in the high frequency hybrid -
model of a bipolar transistor
in the high frequency hybrid - model of a bipolar transistor represents the [ ]
a) Emitter diffusion capacitance b) Depletion region capacitance
c) Emitter-base junction capacitance d) Sum of a and c.
4. The value of is given by the relation [ ]
is given by the relation [ ] a) 
b) 
c) 
d) None
b) c) d) None5. The value of 
is given by [ ]
is given by [ ] a) 
b) c) 
d) None
b) c) d) None6. The value of at room temperature is [ ]
at room temperature is [ ] a) 
b) 
c) 
d) None
b) c) d) None7. Base spreading resistance is given by the relation [ ]
a) 
b) 
c) 
d) None
b) c) d) None8. The value of 
is given by [ ]
is given by [ ] a) b) 
c) 
d) None
b) c) d) None9. The value of output conductance 
of a CE amplifier is [ ]
of a CE amplifier is [ ] a) 
b) 
c) 
d) None
b) c) d) None10. If 
, determine value of 
[ ]
, determine value of [ ] a) 200 b) 100 c) 300 d) None
FILL IN THE BLANKS
11. _________is the low frequency hybrid- model of BJT represents the effect of feedback between the emitter-base junction and collector –base junction due to early effect.
model of BJT represents the effect of feedback between the emitter-base junction and collector –base junction due to early effect.12. Typical value of 
is______
is______13. Hybrid model is also known as ________ model .
14. 
is hybrid – equivalent circuit is ___________
is hybrid – equivalent circuit is ___________15. Expression for in terms of 
and 
is ___________
in terms of and is ___________TRUE OR FALSE
16. rb’e is proportional to 1/IC
17.High frequency hybrid pie conductance can be expressed in terms of low frequency
H parameters
18. At very low frequencies, all the circuit capacitors of the circuit are open circuited for transistor amplifiers
19. In a common emitter amplifier, Output and input ac currents are always out of phase
20. Introduction of an un bypassed resistance in the emitter terminal results in
Increase in input resistance
Answers
1. | B | 6. | B | 11. | The resistance rb’c | 16. | T |
2. | A | 7. | A | 12. |  | 17. | F |
3. | D | 8. | B | 13. | Giacoletto | 18. | T |
4. | A | 9. | A | 14. | incremental resistance | 19. | F |
5. | A | 10. | A | 15. |  | 20. | T |
UNIT –V
MULTIPLE CHOICE QUESTIONS
1. A negative feedback amplifier is characterized by [ ]
a. Increased overall voltage gain
b. Increased Gain-bandwidth product
c. Increased harmonic and phase distortions
d. Improved linearity of operation
2. Feedback in a transistor circuit refers to [ ]
a. Subtracting a fraction of the output voltage from input voltage
b. Adding a fraction of the output voltage to the input voltage
c. Injecting a fraction of output voltage or current In to the Input
d. Injecting the output signal of the circuit in to the input signal
3. Advantage of negative feedback In amplifiers Is [ ]
a. Increased voltage gain
b. Increased gain-bandwidth product
c. Reduced harmonic, amplitude and phase distortions
d. Possibility of stable oscillation
4. If the feedback network In an amplifier is connected In shunt with both input and output terminals, It is a [ ]
a. Voltage series type feedback amplifier
b. Voltage shunt type feedback amplifier
c. Current series type feedback amplifier
d. Current shunt type feedback amplifier
5. Feedback network connected is in series with both the input and output terminals, then It Is a [ ]
a. Voltage series type feedback amplifier
b. Voltage shunt type feedback amplifier
c. Current series type feedback amplifier
d. Current shunt type feedback amplifier
6. Feedback network connected is in series with the output terminals and in shunt with the input terminals, [ ]
the amplifier is a
a. Voltage series type feedback amplifier
b. Voltage shunt type feedback amplifier
c. Current series type feedback amplifier
d. Current shunt type feedback amplifier
7. Feedback network connected is In shunt with the output terminals and in series with the input terminals, the amplifier is a [ ]
a. Voltage series type feedback amplifier
b. Voltage shunt type feedback amplifier
c. Current series type feedback amplifier
d. Current shunt type feedback amplifier
8. If the loop gain of a negative feedback amplifier is 11, the open ioop gain of 180 due to negative feedback decreases to a closed loop gain of [ ]
a. 15
b. 6
c. 16
d. 11
9. A common example of a voltage series type feedback amplifier is [ ]
a. A cascade amplifier
b. A common emitter amplifier
c. An unbypassed common emitter amplifier
d. An emitter follower
10. In a voltage series feedback amplifier, the Input Impedance due to feedback becomes
a. Infinity [ ]
b. Zero
c. Less
d. More
FILL IN THE BLANKS
11. The gain of an amplifier with negative feedback incorporated is refered to-----------
12. The feedback ratio In a negative feedback amplifier is always ------------
13.Voltage shunt feedback amplifiers are also referred to as-------------------
14. Voltage series feedback amplifiers are also referred to as----------
15. A stable feedback amplifier operates on------------
TRUE OR FALSE
16. Gain-Bandwidth product remains the same even with feedback
17. A feedback network introduces only magnitude reduction of output signal
18. With negative feedback in amplifiers , circuit exhibits oscillations at a suitable frequency
19.due to negative feedback of an amplifier, Gain becomes insensitive to temperature variations
20. A negative feedback amplifier is characterized by increased overall voltage gain
Answers:
1. | D | 6. | D | 11. | Closed loop gain | 16. | T |
2. | C | 7. | A | 12. | less than 1 | 17. | F |
3. | C | 8. | A | 13. | Trans resistance amplifiers | 18. | F |
4. | B | 9. | D | 14. | Voltage amplifiers | 19. | T |
5. | C | 10. | D | 15. | Out-of-phase feedback | 20. | F |
UNIT –IV
OSCILLATORS
MULTIPLE CHOICES
1.condition for oscillations in a common emitter configuration oscillator is [ ]
a.Aβ <1 b Aβ >1 c. Aβ =1 d. Aβ =-1
2.A sinusoidal oscillator is [ ]
a. A DC amplifier b. An AC amplifier c. An energy converter from DC to AC d. An energy converter from AC to DC
3.According to Barkhausen criterion for oscillations, the loop gain of positive feedback circuit should be equal to [ ]
a.Zero b.-1 c. +1 d. infinity
4.An oscillator requires [ ]
a. No feedback b. Positive feedback c. Negative feedback d. None
5.A major benefit in RC phase shift oscillator is [ ]
a. High frequency oscillations
b. Possibility of very large output amplitudes
c. Large feedback for ease of initiating oscillations
d.Good frequency stability
6. The feedback factor, of colpitts oscillator is given by [ ]
a. (L1+L2+2M) b.C1C2/C1+C2 c.C1/C2 d.L1/L2
7.In a Hartley oscillator , the feedback network used is [ ]
a.Two capacitors in series and an inductor in parallel with them
b. Two inductors in series and a capacitor in parallel with them
c.Two inductors in parallel with a capacitors
d.Only one inductor and one capacitor in parallel
8.Identify the oscillator which does not depend on inductance for oscillation [ ]
a.Hartley oscillator b.Colpitts oscillator
c.Crystal oscillator d. Wien bridge oscillator
9.Type of feedback used in Wien bridge oscillator is [ ]
a. –ve feedback b.+ve feedback
c. Both a & b d. No feedback
10.A disadvantage of crystal oscillator is that it is [ ]
a. Rugged and cannot be used for High frequency circuits
b. Fragile and useful only in high power circuits
c. Fragile and useful only in low power circuits
d. Rugged and useful only in high power circuits
FILL IN THE BLANKS
11.Equivalent circuit of a crystal is represented as______________________________
12. If the thickness of the quartz crystal is reduced then the frequency of oscillation is
__________________
13. Crystal oscillator works based on ________________ property.
14. The feedback factor of a Hartley oscillator is _________________
15. A demerit of an RC phase shift oscillator is ___________________
TRUE OR FALSE
16.A sinusoidal oscillator always uses negative feedback
17. Minimum value of the gain of the common emitter configured RC phase shift oscillator is 29.
18. A crystal oscillator is described by two resonant frequencies.
19. A disadvantage of crystal oscillator is low frequency oscillations.
20. Frequency stability is better in Colpitts oscillator.
Answers:
1. | C | 6. | A | 11. | A series RLC circuit in parallel with a capacitor | 16. | T |
2. | C | 7. | B | 12. | Increases | 17. | T |
3. | B | 8. | D | 13. | Piezo electric effect | 18. | T |
4. | B | 9. | C | 14. | C1/C2 | 19. | F |
5. | D | 10. | C | 15. | Low output amplitudes | 20. | F |
UNIT –V
LARGE SIGNAL AMPLIFIERS
MULTIPLE CHOICE
1. The maximum efficiency of class –A amplifier is [ ]
a) 15% b) 25% c) 50% d) 90%
2. The maximum efficiency of transformer coupled class-A amplifier [ ]
a) 15% b) 25% c) 50% d) 90%
3. Ina transistor puss pull amplifier [ ]
a) There is no dc present in the output
b) There is no ac present in the output
c) Both a and b d) None
4. Power conversion efficiency of a class AB amplifier [ ]
a) 15% b) 78.5% c) 50% d) 90%
5. If large amount of power are required a push pull amplifier is designed for
operation as [ ]
a) class A b) class B c) class C d) class D
6. Which of the following amplifier has maximum efficiency [ ]
a) class AB push pull b) class A single ended
c) class B push pull transformer coupled d) None
7. A class-A transformer coupled transistor power amplifier is required to drive a power
Output of 10 watts. The maximum power rating of the transistor should be
less than [ ]
a) 5W b) 10W c) 15W d) 20W
8. Which of the following has maximum distortion [ ]
a) class A b) class B c) class C d) class D
9. The push pull amplifier is free from [ ]
a) Saturation b) Noise c) Second harmonic distortion d) None
10. Large signal amplifier are called as [ ]
a) Voltage amplifier b) Current amplifier
c) Power amplifier d) None
FILL IN THE BLANKS
11. In class C amplifier, full cycle conduction of the load current is achieved by
employing _____________
12. If the magnitude of signal is small and operating point swing is with in the active region, that amplitude is classified as ____________.
13. In class B amplifier, Q-point is set _________ of the active device.
14. In class A amplifier flow of electric current in terms of i/p signal cycle is for ------------
15. The power dissipation in class-c amplifier is normally __________
TRUE OR FALSE
16. Beta of power transistor is low [ ]
17. Non-linear distortion is maximum in class B mode [ ]
18. A centered Q point allows a maximum undistorted output swing [ ]
19. even harmonics are not present in the o/p of class A transformer
coupled amplifier [ ]
20. Max conversion efficiency of a series fed class A power amplifier is 75%[ ]
Answers
1. | B | 6. | B | 11. | push pull configuration. | 16. | T |
2. | C | 7. | D | 12. | small signal amplifier. | 17. | F |
3. | A | 8. | C | 13. | near cut off | 18. | T |
4. | A | 9. | C | 14. | 360 | 19. | F |
5. | B | 10. | C | 15. | very low | 20. | F |
UNIT – VI
LINEAR WAVE SHAPING
Multiple Choice Questions:
1.High pass RC circuits produces position and Negative spikes in the following condition [ ]
a) RC << T b) RC >> T c) RC = T d) RC > T
2. Relation between percentage tilt and lowest 3dB frequency is [ ]
a) 
X 100 % b) π f. f 1 X 100 % c) 
X 100 % d) 
X 100%
X 100 % b) π f. f 1 X 100 % c) X 100 % d) X 100% 3.In clampers the essential component is ____________________ [ ]
a) Resistor b) capacitor c) inductor d)None
4. The positive peaks of input are clamped to zero level. The type of clamper is ________ [ ]
a) Negative clamper b)Positive clamper c)Modified clamper d)synchronous clamper
5. Clamping circuits are used: [ ]
a) To fix the extremity of the waveform at some level
b) To remove the middle portion of the waveform
c) To compare voltages
d) To reduce the amplitude of the signal.
6. Clamping theorem is given by_ [ ]
a)Ar/Af=Rf/R b) Af / Ar=R/ Rf c) Ar/ Af=R/ Rf d) Af / Ar= Rf/R
7.A clipping circuit does not contain the following element. [ ]
a)resistor b)capacitor c)transistor d)junction diode
8.A clamping circuit should be called as -------- [ ]
a) dc restorer b) dc re inserter c) dc inserter d) all the above
9.The typical value of series resistance of a clipper is_ [ ]
a)R=RfRr b)R=√ RfRr c)R=Rf/ Rr d)R= Rf/ Rr
10.In emitter coupled clipper total input voltage swing ∆ Vi to carry the output is_ [ ]
a) ∆ Vi =ηVT /4.4 b) ∆ Vi =4.4 ηVT c) ∆ Vi= η /4.4 VT d) ∆ Vi=4.4/ ηVT
BLANKS:
11. A comparator is a basic building block in a system used to analyze the ____________ distortion of noise generation.
12. A sinusoidal wave is converted into trapezoidal wave by using ________________________ clipper
13. Name the circuit which is used to convert analog signals into digital signal_________________
14.The break point of junction diode depends on__________
15.Comparator make use of __________ nature of the output.
TRUE / FALSE:
16. Diode clippers are used for only one level clipping [T/F]
17. clipping circuits require non linear elements [T/F]
18. In transistor clipper, the 1/P signal appear without distortion during its active region operation.[T/F]
19.The diode break point changes by about 2mv/oC with increase in temperature. [T/F]
20.Clipping circuit is a regenerative feedback comparator. [T/F]
ANSWERS:
1 | A | 6 | D | 11 | AMPLITUDE | 16 | F |
2 | C | 7 | B | 12 | DOUBLE ENDED | 17 | T |
3 | B | 8 | D | 13 | COMPARATOR | 18 | T |
4 | A | 9 | B | 14 | CUT IN VOLTAGE | 19 | T |
5 | C | 10 | B | 15 | NON LINEAR | 20 | F |
UNIT – VII
SWITCHING CHARACTERISTICS OF DEVICES
Multiple Choice Questions:
1. An ideal diode should have ____________________ [ ]
a) Zero forward resistance and Zero reverse resistance b) Zero R f & infinity Rr
c) Infinity R f & Zero Rr d) Infinity R f & infinity Rr
2. The time interval between application of base current and the start of collector current is [ ]
a) rise time b) delay time c)storage time d) fall time
3.In the Si transistor , typical valve of V be ( active ) at room temperature is ____ [ ]
a) 0 .3V b) 0. 7 V c) 0.6 V d) 0. 2V
4.The reverse saturation current is in the order of Ge diode _____________ [ ]
a) mA b) micro A c) n A d) Ampers
5.The switching of a transistor is characterized by __________________ [ ]
a) Cut off b)Saturation c) active d) cutoff and saturation
6.The reverse saturation current of a diode doubles for every [ ]
a)20 oC rise in temp. b)10oC rise in temp. c)15oC rise in temp d)40oC rise in temp.
7.In transistor cutoff region the biasing conditions are_ [ ]
a)EB junction forward biased&CB junction reverse biased
b)EB junction reverse biased&CB junction forward biased
c) EB junction forward biased& CB junction forward biased
d) EB junction reverse biased & CB junction reverse biased
8.ICBO for a Si transistor is in the order of_ [ ]
a)mA b)µA c)nA d)Ampere
9.The transistor is under saturation when [ ]
a)IBC/h FE b) IB<= IC/h FE c) IB> IC/h FE d) IB>= IC/h FE
10.VBE cutoff of Ge n-p-n transistor at 25oC is_ [ ]
a)0.1v b)0.3v c)0.2v d)-0.1v
BLANKS:
11 Zener breakdown is due to the existence of _______________________
12 A transistor acts as a closed switch when it is in ____________region.
13. The capacitance appears across reverse biased diode is called _____________________
14._____________is the reciprocal of slope of V-I characteristics.
15.Transistor OFF time is equal to the sum of _____________& _____________.
.
TRUE / FALSE:
16.The transistor acts as open switch when it is in cut off region. [T/F]
17.Reverse saturation current doubles for every 20 0 C rise in temperature in case of diode [T/F]
18. The mechanism due to early effect is called reach through [T/F]
19.the breakdown voltage of a transistor is due to avalanche breakdown. [T/F]
20.the time interval required to fall from 90% to 10% is delay time. [T/F]
ANSWERS:
1 | B | 6 | B | 11 | STRONG ELECTRIC FIELD | 16 | T |
2 | B | 7 | D | 12 | SATURATION REGION | 17 | F |
3 | C | 8 | C | 13 | TRANSITION CAPACITANCE | 18 | T |
4 | B | 9 | D | 14 | DYNAMIC RESISTANCE | 19 | T |
5 | D | 10 | D | 15 | STORAGE AND CALL TIME | 20 | F |
UNIT – VIII
MULTIVIBRATORS
Multiple Choice Questions:
1. A multivibrator Produces ________________ [ ]
a) Sine waves b) distorted sine waves c) square waves d) saw tooth voltages
2. A monostable multivibrator can be used to generate _______________ [ ]
a) pulse b) sweep c) sinusoids d) square
3.Which of the following circuit can be used convert a sine wave to a square wave ____ [ ]
a) A bistable multivibrator b) astable multivibretor c) schmitt trigger d) all of the above
4.which of the following does not require triggering __________________ [ ]
a)schmitt trigger b) Astable multivibrator c) Monostable multivibrator d) Bistable multivibrator
5.Unsymmetrical Triggering is adopted in following circuit _________________ [ ]
a) E mitter coupled binary b) Mono stable multi c) schmit trigger d) astable multi
6.Oneshot is alternate name of the following cicuit. [ ]
a)monostable multi b)bistable multi c)astable multi d)Schmitt trigger
7.In bistable multivibrators the coupling elements are_____________ [ ]
a)both capacitors b)both resistors c)one capacitor and one resistor d)none of the above
8.. In monostable multivibrator the coupling elements are: [ ]
a)both resistors b)both capacitors c)one capacitor and one resistor d)short circuits
9.The expression for time period of astable multi_ [ ]
a)t= 0.69RC b)t=1.38 RC c)t=1.44/(RA+RB)C d)RC
10.Schmitt trigger converts sine wave into [ ]
a)triangular b)sine c)square d)trapezoidal
BLANKS:
11. The capacitors which reduces the transition time incase of bistable multi are called ___________
12.________________ multivibrator is used as a memory element.
13.Astable multi is referred as ____________________ to _____________________converter
14.Schmitt trigger is used as______________
15.___________triggering requires two triggering pulses from separate sources.
TRUE / FALSE:
16.Monostable multivibrator can be used as a gating circuit. [T/F]
17.The voltage difference between UTP & LTP in case of Schmitt trigger is called Hysteresis voltage [T/F]
18.In symmetrical triggering , triggering signal induces the transition in only one direction [T/F]
19.Astable multi has one quasi stable state. [T/F]
20.Monostable multi is used to generate pulses. [T/F]
ANSWERS:
1 | C | 6 | A | 11 | SPEED UP CAPACITOR/ COMMUTATING CAPACITOR | 16 | T |
2 | A | 7 | B | 12 | BISTABLE | 17 | T |
3 | C | 8 | C | 13 | VOLTAGE TO FREQUENCY | 18 | F |
4 | B | 9 | B | 14 | AMPLITUDE COMPARATOR | 19 | F |
5 | B | 10 | C | 15 | UNSYMMETRICAL TRIGGERING | 20 | T |
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