PDC
UNIT-1(Linear wave shaping)
1. The waveform
which preserves its form when transmitted through a linear network is a
___________. [ b
]
(a)Sine wave (b) Step
signal (c) impulse signal (d) ramp signal
2. An RC high pass circuit has R= 1kΩ and C=0.5
μF. Its lower cutoff frequency is [ b]
(a)
zero (b) 318.3 Hz (c) 1kHz (d) infinity
3. For a integrator, if input is square wave
then the output waveform is _____ [ a]
(a)
Impulse (b) Sawtooth wave (c) Triangular wave (d) Both a and c
4. A ringing circuit has a quality factor Q=24.
This circuit will ring for how many number of cycles? [ c]
(a)
24 (b) 12 (c) 8 (d) 6
5. The rise time of the output of a low pass RC
circuit is given by [c ]
(a)
2.2 RC (b) 0.35/fH (c) 2.2τ (d) all the above
6. What is the response of step input to a high
pass RC circuit [ a ]
a) V e-t/RC b)
V (1- et/RC)
c) V et/RC
d) V(1- e-t/RC )
7. When RC high pass circuit act as a
differentiator? [ a]
a)
RC<<T b) RC>>T c)RC=T d)RC=0
8. What is the name of the circuit which
converts square wave in to spikes [ c]
a)
Low pass RC b) Bi stable multi c) High pass RC d) Monoshot
section II: fill in the blanks:
9. For DC input
signal capacitor C acts as a open circuit
10. The average
value of the output value of an RC high pass circuit is Zero
11.
In RC integrator circuit the output is taken across capacitor
12. -------------is the condition
for an RC high pass circuit to acts as a differentiator.
13.
Time constant of RL circuit is L/R
14. The process of converting pulses into
spikes is called Tilt
15. Write the relationship between
time constant and tilt? Linear wave shaping
UNIT-2
: Non linear wave shaping
1. A
comparator is a basic building block in a system used to analyze the --------
distribution of noise generated in active device [ b]
a) Both frequency and phase b) Amplitude c) Phase d) Frequency
2. Zener
diode has ---------- temperature coefficient [
b]
a) sometimes
positive and sometimes negative b) Only negative.
c) Both positive and negative d) Only positive
3. A
clamping circuit is also called as ____________. [ c ]
(a) dc restorer (b) dc reinserter (c) both a and b (d) none of the above
4. A
clipping circuit consists of ___________. [ c]
(a) Resistor (b) Diode (c) both a and b (d) c and capacitor
section II: fill in
the blanks
5. The clamping theorem is given by Af/Ar=Rf/R
6. When the diode is forward biased it acts as closed switch
UNIT-III: SWITCHING CHARACTERISTICS OF
DEVICES
1. Common base configurations is
little used because [ C]
a) High voltage gain b) High current gain c) It has
low input impedance d) High input impedance
2. The Vce
(sat) of Si n-p-n transistor at 27 c is [ B ]
a) 0.7 v b) 0.3 v c) 0.8 v d) 0.1 v
3. Turn off
time of the transistor is = ------- [A ]
a)
toff =tf +ts b) toff
=tf +ton c) toff =tfd +ts d) toff =ton +ts
Unit-IV: multivibrators
Section-I: Multiple choice questions
1.
Monostable multivibrators generates [ b ]
a) Pulse wave form b) Ramp signal c) Sine wave d) Square wave
2. A
sinusoidal waveform can be converted to a square waveform by using _______ [ c ]
(a) Astable
multivibrator (b) Bitable multivibrator (c ) Schmitt trigger (d) None of the
above
3. A Schmitt
trigger is a __________. [ a]
(a) counter (b)
Voltage to frequency converter (c)
Comparator (d) None of the above
Section-I: Fill in the blanks:
1. A bistable multivibrator is used for 0.5MHz
2. The time constant of a monostable multivibrator is 2.2τ = 2.2RC = 0.35/f2
3. _______________ circuit is used to generate the sequence of pulses which
are regularly spaced in time
4. No of
quasi stable states of astable is 2
5. The expression of pulse width for monostable
multivibrator is (T/2RC) X 100
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