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CMR INSTITUTE OF TECHNOLOGYNo.132, AECS Layout, I.T.P.L. Road, Kundalahalli, Bangalore- 560 037
Ph: 080- 28524466, Extn: 213 (EC Dept. HOD)
A LAB MANUAL ON
ANALOG ELECTRONICS
Subject Code: 06ESL37
(As per VTU Syllabus)
PREPARED BY
Staff members - Dept. of E&C
No.132, AECS Layout, I.T.P.L. Road, Kundalahalli, Bangalore- 560 037Ph: 080- 28524466, Extn: 213 (EC Dept. HOD)
CONTENTS
EXPT. NO.
NAME OF THE EXPERIMENTPAGE NO.
01 Half wave, full wave and bridge rectifier 01
02 Clamping circuits 10
03 Clipping circuits 16
04 RC coupled amplifier using BJT and FET 23
05 Hartley oscillator / Colpitt’s oscillator 31
06 Crystal oscillator 38
07 RC phase shift oscillator 41
08 Voltage series feedback amplifier using BJT 45
09Thevenin’s theorem and maximum power transfer theorem
51
10 Series and parallel resonance circuits. 55
11 Darlington emitter follower. 59
12 Class-B push pull power amplifier. 63
13 Bibliography 65
14 Vivo-voce questions 66
Analog Electronics Laboratory Manual - 06ESL37
Ex.No:01 HALF WAVE, FULL WAVE AND BRIDGE RECTIFIER HALF WAVE RECTIFIER
AIM:
To study Half Wave Rectifier and to calculate ripple factor, efficiency and
regulation with filter and without filter.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Diodes BY127 1 No.
2. Capacitor 0.1µf, 470µf Each 1 No.
3. Power Resistance Board 1 No.
4. Step down Transformer 12 V 1 No.
5. CRO, Multimeter, Milliammeter, Connecting Board
THEORY:
Half wave rectifier circuit consists of resistive load, a diode and source of
ac voltage, all connected in series. In half wave rectifier, rectifying element
conducts only during positive half cycle of input ac supply. The negative half
cycles of ac supply are eliminated from the output. The dc output waveform is
expected to be a straight line but the half wave rectifier gives output in the form
of positive sinusoidal pulses. Thus the output is called pulsating dc.
CIRCUIT DIAGRAM:
HALF WAVE RECTIFIER WITHOUT FILTER CAPACITOR
Department of Electronics & Communication Engg. – CMRIT 1
C2
0.1UFBY127
A K
RL
AC(230V/50HZ)
12V
12V
0
Step downTransformer
A
Ammeter(0-250mA)
+ -
VODC VOAC
Analog Electronics Laboratory Manual - 06ESL37
HALF WAVE RECTIFIER WITH FILTER CAPACITOR
DESIGN:
Given
Ripple = r = Vo rms / VO DC = 1.21Design for the filter capacitor
Ripple = 1/(43 f C RL)
Given r = 0.25 C = 1/(43 f r RL)
RL = 50
f = 50Hz
= 461.88F 470F Efficiency = PDC /PAC (I2
DC * RL) / [(Irms)2 * (RL + RF)]
Regulation % Regulation =
Department of Electronics & Communication Engg. – CMRIT 2
C2
0.1UFBY127
A K
RL
AC(230V/50HZ)
12V
12V
0
Step downTransformer
A
Ammeter(0-250mA)
+ -
470UF
+
-
C1
VODC VOAC
Analog Electronics Laboratory Manual - 06ESL37
PROCEDURE:
1. Connections are made as shown in the circuit diagram
2. Switch on the AC power supply
3. Observe the wave form on CRO across the load resistor and measure the o/p amplitude and frequency.
4. Note down RL, IDC, VODC, VINAC, and VOAC in the tabular column for different load resistances.
5. Calculate the ripple and efficiency and Regulation for each load resistance.
6. Repeat the above procedure with filter capacitor.TABULAR COLUMN:
Sl. No.
RL IDC VO (DC)VIN
(AC)VO (AC) Ripple Efficiency
Regulation
WAVEFORMS:
20
t
0
- 20
0 Vo (Without Filter)
t
Vo (with filter)
t
FULL WAVE RECTIFIER
AIM:
To study the full wave rectifier and to calculate ripple factor and efficiency
and Regulation with filter and without filter.
Department of Electronics & Communication Engg. – CMRIT 3
VC
VIN
VO
Analog Electronics Laboratory Manual - 06ESL37
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Diodes BY127 2 Nos.
2. Capacitor 0.1µf, 470µf Each 1 No.
3. Power Resistance Board 1 No.
4. Step down Transformer 12 V 1 No.
5. CRO, Multimeter, Milliammeter, Connecting Board
THEORY:
The center tapped full wave rectifier circuit is similar to a half wave
rectifier circuit, using two diodes and a center tapped transformer. Both the input
half cycles are converted into unidirectional pulsating DC.
CIRCUIT DIAGRAM:
FULL WAVE RECTIFIER WITHOUT FILTER CAPACITOR
FULL WAVE RECTIFIER WITH FILTER CAPACITOR
DESIGN:
Vin rms = 12VVin m = 2Vin rms = 16.97V
VO DC = 2Vm/ = 10.8V
Given VO DC = 10V
Department of Electronics & Communication Engg. – CMRIT 4
Step down
C2
0.1UFBY127
A K
RL
AC(230V/50HZ)
12V
12V
0
Transformer
A
Ammeter(0-250mA)
+ -
VO(DC)
BY127
A K
VO (AC)
(230V/50HZ)
C2
0.1UFBY127
A K
RL
AC
12V
12V
0
Step downTransformer
A
Ammeter(0-250mA)
+ -
470UF
+
-
C1
VO(DC)
BY127
A K
VO(AC)
Analog Electronics Laboratory Manual - 06ESL37
IO DC = 100mA
RL = VO DC / IO DC = 100
Ripple = r = Vo rms / VO DC = 0.48Design for the filter capacitor
Ripple = 1/(43 f C RL)
Given r = .06 C = 1/(43 f r RL)
RL = 100
f = 50Hz
= 470UF
Efficiency = PDC /PAC (I2DC * RL) / [(Irms)2 * (RL + RF)]
Regulation % Regulation =
PROCEDURE:
1. Connections are made as shown in the circuit diagram
2. Switch on the AC power supply
3. Observe the wave form on CRO across the load resistor and measure the o/p amplitude and frequency.
4. Note down RL, IDC, VODC , Vinac, Voac in the tabular column for different load resistances.
5. Calculate the ripple and efficiency and regulation for each load resistance.
6. Repeat the above procedure with filter capacitor.
TABULAR COLUMN:
Sl. No.
RL IDC VO (DC)VIN
(AC)VO (AC) Ripple Efficiency
Regulation
WAVEFORMS:
t
0
-
Department of Electronics & Communication Engg. – CMRIT 5
Analog Electronics Laboratory Manual - 06ESL37
0 Vo (Without Filter)
t
Vo (with filter)
t
Department of Electronics & Communication Engg. – CMRIT 6
VC
VIN
VO
Analog Electronics Laboratory Manual - 06ESL37
BRIDGE RECTIFIER
AIM:
To study the bridge rectifier and to calculate ripple factor and efficiency and
regulation with filter and without filter.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Diodes BY127 4 Nos.
2. Capacitor 0.1µf, 470µf Each 1 No.
3. Power Resistance Board 1 No.
4. Step down Transformer 12 V 1 No.
5. CRO, Multimeter, Milliammeter, Connecting Board
THEORY:
The bridge rectifier circuit is essentially a full wave rectifier circuit, using
four diodes, forming the four arms of an electrical bridge. To one diagonal of the
bridge, the ac voltage is applied through a transformer and the rectified dc
voltage is taken from the other diagonal of the bridge. The main advantage of
this circuit is that it does not require a center tap on the secondary winding of
the transformer; ac voltage can be directly applied to the bridge.
The bridge rectifier circuit is mainly used as a power rectifier circuit for
converting ac power to dc power, and a rectifying system in rectifier type ac
meters, such as ac voltmeter in which the ac voltage under measurement is first
converted into dc and measured with conventional meter.
CIRCUIT DIAGRAM:
BRIDGE RECTIFIER WITHOUT FILTER CAPACITOR
Department of Electronics & Communication Engg. – CMRIT 7
RL
- +
BRIDGE
1
4
3
2
C2
0.1UF
AC(230V/50HZ)
12V
12V
0
Step downTransformer
Vo
A
Ammeter(0-250mA)
+ -
Analog Electronics Laboratory Manual - 06ESL37
BRIDGE RECTIFIER WITH FILTER CAPACITOR
C1
470UF
RL
- +
BRIDGE
1
4
3
2
C2
0.1UF
AC(230V/50HZ)
12V
12V
0
Step downTransformer
Vo
A
Ammeter(0-250mA)
+ -
+ -
DESIGN:
Vin rms = 12VVin m = 2Vin rms = 16.97V
VO DC = 2Vm/ = 10.8V
Given VO DC = 10V
IO DC = 100mA
RL = VO DC / IO DC = 100
Ripple = r = Vo rms / VO DC = 0.48 Design for the filter capacitor
Ripple = 1/(43 f C RL)
Given r = .06 C = 1/(43 f r RL)
RL = 100
f = 50Hz
= 470UF
Efficiency = PDC /PAC
= (I2DC * RL) / [(Irms)2 * (RL + RF)]
Regulation % Regulation =
Department of Electronics & Communication Engg. – CMRIT 8
Analog Electronics Laboratory Manual - 06ESL37
PROCEDURE:
1. Connections are made as shown in the circuit diagram
2. Switch on the AC power supply
3. Observe the wave form on CRO across the load resistor and measure the o/p amplitude and frequency.
4. Note down RL, IDC, VODC , Vinac, Voac in the tabular column for different load resistances.
5. Calculate the ripple factor, efficiency and regulation for each load resistance.
6. Repeat the above procedure with filter capacitor.
TABULAR COLUMN:
Sl. No.
RL IDC VO (DC)VIN
(AC)VO (AC) Ripple Efficiency
Regulation
WAVEFORMS:
Vin
20
t
0
- 20
Vo
0 Vo (Without Filter)
t
Vo (with filter)
VC
t
RESULT:
Ex.No:02 CLAMPING CIRCUITS
Department of Electronics & Communication Engg. – CMRIT 9
Analog Electronics Laboratory Manual - 06ESL37
AIM:
Design a clamping circuit for the given output.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Diodes BY127 1 No
2. Capacitors 0.1 F 1 No
Signal generator, Cathode Ray Oscilloscope (CRO) with Probes, Dual Power Supply, Connecting Board
THEORY: A clamper is one, which provides a D.C shift to the input signal. The D.C
shift can be positive or negative. The clamper with positive D.C shift is called
positive clamper and clamper with negative shift is called negative clamper.
Consider a clamper circuit shown below.
In the positive half cycle as the diode is forward biased the capacitor charges to
the value with the polarity as shown in the figure. In the negative half
cycle the diode is reverse biased. Hence the output is .
Initially let us assume that the capacitor has charged to i.e.
(5 – 0.5) = 4.5V
Then in the positive half cycle diode is forward biased and applying KVL to
the loop,
Vin –VC –V0 = 0 V0 =Vin –VC
When Vin = 0 V0 = 0 - 4.5 = - 4.5V
Vin = 5V V0 = 5 – 4.5 = 0.5V
In the negative half cycle
When Vin = -5V V0 = -5 – 4.5 = -9.5V
The output shifts between 0.5V and – 9.5V.Here the output has shifted
down by 4.5V
The peak to peak voltage at the output of a clamper is the same as that of
the input.
Department of Electronics & Communication Engg. – CMRIT 10
D 1
B Y 1 2 7
0 . 1 u
+ -
VoVin
C
Analog Electronics Laboratory Manual - 06ESL37
CIRCUIT DIAGRAM AND DESIGN:
Given Vin = 10V (p-p)
A] In the positive half cycle:
Diode is forward biased.
Applying KVL to loop 1
Vin – VC – VD = 0
VC = Vin – VD
= 5 - 0.5 4.5V
In the negative half cycle:
Vin – VC – V0 = 0
V0 = Vin – VC
When Vin = 0 V0 = - 4.5V
When Vin = 5V V0 = 0.5V
When Vin = -5V V0 = -9.5V
B]In the negative half cycle:
Diode is forward biased
Applying KVL to loop 1
Vin + VC + VD = 0
VC = - ( Vin + VD)
VC = - (-5 + 0.5)
= 4.5V
In the positive half cycle:
Diode is reverse biased.
Apply KVL to the loop
Vin + VC – V0 = 0
V0 = Vin + VC
When Vin = 0 V0 = 4.5V
When Vin = 5V V0 = 5 + 4.5 = 9.5V
When Vin = - 5V V0 = - 0.5V
Department of Electronics & Communication Engg. – CMRIT 11
D 1
B Y 1 2 7
0 . 1 u
+ -
VoVin
C
D 1BY1 2 7
0 .1 u
- +
VoVin
C
Analog Electronics Laboratory Manual - 06ESL37
C] Assume VR = 2V
In the positive half cycle:
Diode is forward biased.
Apply KVL to loop 1
Vin – VC – VD – VR = 0
VC = Vin – VD – VR
= 5 - 0.5 – 2
= 2.5V
In the negative half cycle:
Diode is reverse biased
Vin – VC – V0 = 0
V0 = Vin – VC
When Vin = 0V V0 = - 2.5V
When Vin = 5V V0 = 2.5V
When Vin = -5V V0 = -7.5V
D] Assume VR = 2V
In the positive half cycle:
Diode is forward biased and the capacitor charges.
Apply KVL to loop 1
Vin – VC – VD + VR = 0
VC = Vin – VD + VR
= 5 –0.5 +2
= 6.5V
In the negative half cycle:
Vin – VC – V0 = 0
V0 = Vin – VC
When Vin = 0V V0 = - 6.5V
When Vin = 5V V0 = - 1.5V
When Vin = -5V V0 = - 11.5V
Department of Electronics & Communication Engg. – CMRIT 12
Vo
0.1u
D1 BY127
+ -
Vin
C
VR
VoD1 BY127
0.1u
C
Vin
-+
VR
Analog Electronics Laboratory Manual - 06ESL37
E]In the negative half cycle:
Assume VR = 2V
Diode is forward biased and capacitor charges.
Apply KVL to the loop1
Vin + VC + VD + VR = 0
VC = - ( Vin + VR + VD)
= - (- 5 + 0.5 + 2)
= 2.5V
From the fig. we see that
Vin + VC – V0 = 0
V0 = Vin + VC
When Vin = 0 V0 = 2.5V
When Vin = 5V V0 = 7.5V
When Vin = -5V V0 = -2.5V
F] VR = 2V
In the negative half cycle:
Diode is forward biased and capacitor charges.
Apply KVL to loop 1
Vin + VC + VD - VR =0
VC = - ( Vin + VD - VR)
= - (- 5 + 0.5 – 2)
= 6.5V
From the circuit we see that,
Vin + VC - V0 =0
V0 = Vin – VC
When Vin =0V V0=6.5V
When Vin = 5V V0= 11.5V
When Vin = - 5V V0= 1.5V
PROCEDURE:
1. Rig up the circuit as shown in the circuit diagram.
2. Give a sinusoidal input of 10V peak to peak
3. Check and verify the output.
Department of Electronics & Communication Engg. – CMRIT 13
Vo
0.1u
D1BY127
VR
C
Vin
- +
Vo
0.1u
D1BY127C
Vin
+-
VR
Analog Electronics Laboratory Manual - 06ESL37
WAVEFORMS:
Vin
5V
0 t - 5V
V0
0.5 0 t
[A] - 4.5
- 9.5
V0
9.5
4.5
[B] 0 t - 0.5
V0
2.5 0
[C] t - 2.5
- 7.5
Department of Electronics & Communication Engg. – CMRIT 14
Analog Electronics Laboratory Manual - 06ESL37
V0
0 t
[D] - 1.5
- 6.5
- 11.5
V0
7.5
2.5
[E] 0 t
- 2.5
V0
11.5
6.5
[F]
1.5
0 t
RESULT:
Department of Electronics & Communication Engg. – CMRIT 15
Analog Electronics Laboratory Manual - 06ESL37
Ex.No:03 CLIPPING CIRCUITS
AIM:
Design a clipping circuit for the given values.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Diodes BY127 1 No
2. Resistors 10 K 1 No
THEORY:
The process by which the shape of a signal is changed by passing the
signal through a network consisting of linear elements is called linear wave
shaping. Most commonly used wave shaping circuit is clipper. Clipping circuits
are those, which cut off the unwanted portion of the waveform or signal without
distorting the remaining part of the signal. There are two types of clippers
namely parallel and series. A series clipper is one in which the diode is
connected in series with the load and a parallel clipper is one in which the diode
is connected in parallel with the load.
CIRCUIT DIAGRAM AND DESIGN:
Assume Vin = 10V (Peak to Peak)
(a) Consider the circuit in fig. 1
In the positive half cycle D is forward biased
V0 = Vin – 0.5 = 5 – 0.5 = 4.5 (0.5V is the diode drop)
In the negative half cycle D is reverse biased
V0 = 0V
(b) Consider the circuit in fig. 2
In the positive half cycle D is reverse biased
V0 = 0V
In the negative half cycle D is forward biased
Applying KVL to the loop
Vin + VD – V0 = 0
V0 = Vin + VD = -5 + 0.5 = - 4.5V
Department of Electronics & Communication Engg. – CMRIT 16
10k
D 1
BY1 2 7Vin Vo
(a)
10k
D 1
BY1 2 7Vin Vo
Analog Electronics Laboratory Manual - 06ESL37
(c) Consider the circuit in fig. 3
Given VR = 2.5V
In the positive half cycle
(i) When |Vin| > |VD + VR|, D is forward biased
Applying KVL, we get
Vin = VD + VR + V0
V0 = Vin – VD – VR
V0 = 5 – 0.5 – 2.5
V0 = 2V
(ii) When |Vin| < |VD + VR|, D is reverse biased
V0 = 0V
In the negative half cycle, D is reverse biased
V0 = 0V
(d) Consider the circuit in fig. 4
Assume VR = 3V
In the positive half cycle, D is reverse biased
V0 = 0V
In the negative half cycle
(i) When |Vin| > |VD + VR|, D is forward biased
Applying KVL, we get
Vin = - VD - VR + V0
V0 = Vin + VD + VR
V0 = -5 + 0.5 + 3
V0 = -1.5V
(ii) When |Vin < |VD + VR|, D is reverse biased
V0 = 0V
Department of Electronics & Communication Engg. – CMRIT 17
D 1
BY1 2 710k
V R
Vin Vo
V R
10k
D 1
BY1 2 7Vin Vo
Analog Electronics Laboratory Manual - 06ESL37
(e) Consider the circuit in fig. 5
Assume VR1 = 2.5V and VR2 = 3V
In the positive half cycle, D2 is reverse biased
(i) When |Vin| > |VD1 + VR1|, D1 is forward biased
Applying KVL, we get
Vin = VD1 + VR1 + V0
V0 = Vin - VD1 - VR1
V0 = 5 - 0.5 – 2.5
V0 = 2V
(ii) When |Vin < |VD1 + VR1|, D1 is reverse biased
V0 = 0V
In the negative half cycle
(i) When |Vin| > |VD2 + VR2|, D2 is forward biased
Applying KVL, we get
Vin = - VD - VR + V0
V0 = Vin + VD2 + VR2
V0 = -5 + 0.5 + 3
V0 = -1.5V
(ii) When |Vin < |VD2 + VR2|, D2 is reverse biased
V0 = 0V
(f) Consider the circuit in fig. 6
During the positive half cycle, D is forward biased
V0 = VD = 0.5V
During negative half cycle, D is reverse biased
V0 = Vin
Department of Electronics & Communication Engg. – CMRIT 18
BY1 2 7 V R2
10kBY1 2 7 V R1 VoD 1Vin
1
2
D 2
10k
D 1
BY1 2 7
VoVin
Analog Electronics Laboratory Manual - 06ESL37
(g) Consider the circuit in fig. 7
During positive half cycle,
D is reverse biased
V0 = Vin
During negative half cycle,
D is forward biased
V0 = -VD = -0.5V
(h) Consider the circuit in fig. 8
During positive half cycle
(i) When |Vin| > |VD + VR|,
D is forward biased
V0 = VD + VR = 0.5 + 2.5
V0 = 3V
(ii) When |Vin| < |VD + VR|, D is reverse biased
V0 = Vin
During negative half cycle, D is reverse biased
V0 = Vin
(i)Consider the circuit in fig. 9
Assume VR = 2.5V
During positive half cycle,
D is reverse biased
V0 = Vin
During negative half cycle
(i) When |Vin| > |VD + VR|,
D is forward biased
Applying KVL to the loop, we get
V0 = -VD - VR = - 0.5 - 2.5
V0 = -3V
(ii) When |Vin| < |VD + VR|,
D is reverse biased
V0 = Vin
During negative half cycle, D is reverse biased
V0 = Vin
Department of Electronics & Communication Engg. – CMRIT 19
10k
D 1BY1 2 7
V R
Vin Vo
10k
D 1BY1 2 7Vin Vo
10k
D 1BY1 2 7
V R
Vin Vo
+
-
Analog Electronics Laboratory Manual - 06ESL37
(j) Consider the circuit in fig. 10
Assume VR1 = VR2 = 2.5V
During positive half cycle, D2 is reverse biased.
(i) When |Vin| > |VD1 + VR1|, D1 is forward biased
V0 = VD1 + VR1 = 0.5 + 2.5
V0 = 3V
(ii) When |Vin| < |VD1 + VR1|,
D1 is reverse biased
V0 = Vin
During negative half cycle,
D1 is reverse biased
(i)When |Vin| > |VD2 + VR2|, D2 is forward biased
Applying KVL to the loop, we get
V0 = -VD2 - VR2 = -0.5 - 2.5
V0 = -3V
(ii) When |Vin| < |VD2 + VR2|, D2 is reverse biased
V0 = Vin
(k) Consider the circuit in fig. 11
Assume VR1 = 3.5V and VR2 = 2V
During positive half cycle
(i) When |Vin| > |VD1 + VR1|
D1 is forward biased and
D2 is reverse biased
V0 = VD1 + VR1 = 0.5 + 3.5 = 4 V
(ii) When |Vin| < |VR2 – VD2|
D1 is reverse biased and
D2 is forward biased
V0 = -VD2 + VR2 = - 0.5 + 2 1.5V
During negative half cycle,
D1 is reverse biased and D2 is forward biased
V0 = -VD2 + VR2 = - 0.5 + 2 V0 = 1.5VPROCEDURE:
1. Rig up the circuit as shown in the fig.2. Give a sinusoidal input of 10V peak to peak.3. Check the output at the output terminal.4. To plot the transfer characteristics, connect channel 1 of the CRO to
the output and channel 2 to the input and press the XY knob5. Adjust the grounds of both the channels to the centre.6. Measure the designed values.
Department of Electronics & Communication Engg. – CMRIT 20
D 1BY1 2 7
V R1 V R2
10k
BY1 2 7Vin
D 2
Vo
1
Vo
Vin
10k
D1
BY127
VR1
BY127
D2
VR2
Vo
Analog Electronics Laboratory Manual - 06ESL37
WAVEFORMS:
Series Clipper
Vin
5
3
0 t
- 3.5
- 5
Vo
4.5
(a) 0 t
Vo(b)
0 t
- 4.5
2.0(c)
0 t
(d) 0 t
-1.5
2
(e) 0 t
-1.5
Department of Electronics & Communication Engg. – CMRIT 21
Vin
Vo
Vin
Vo
Vin
Vo
3
Vin
Vo
-3.5
Vin
Vo
-3.5
3
Analog Electronics Laboratory Manual - 06ESL37
Shunt ClipperVin
+5
0 t
+5
(f) 0.5 t
0.5
-5
4.5
(g) 0 t 0.5
VO
3
(h) t
-5
+5
(i) 0 t
-3
+3
(j) 0 t
-3
+4
1.5
( k ) 0 t
RESULT:
Department of Electronics & Communication Engg. – CMRIT 22
Vin
Vo
Vin
Vo
Vin
Vo
-3.0
Vin
Vo
3.0
Vin
Vo
Vin
Vo
3.0
Analog Electronics Laboratory Manual - 06ESL37
Ex.No:04 RC COUPLED AMPLIFIER - BJT
AIM:
Design an RC coupled single stage BJT amplifier and determine its gain
and frequency response, input and output impedances.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Transistor SL100 1 No
2. Capacitors 0.1 f , 47µf Each 1 No
3. Resistors 22K, 4.7K, 1.2K, 330 Each 1 No
DC Supply, Signal Generator, CRO with Probe
CIRCUIT DIAGRAM:
To Find Input Impedance
To Find the Output Impedance
DESIGN:
Given VCC = 12V, IC = 4mA, = 100.
Department of Electronics & Communication Engg. – CMRIT 23
DRB
RCCOUPLED
AMPLIFIERI/P VOUT
DRB
RCCOUPLED
AMPLIFIERI/P VOUT
00
R2
SL100
CB
CcR1
Vcc = 12 v
CE
RE
~Vs
B
Vo
Rc
22K
4.7K
1.2 K
330
47 f
0.1 f
0.1 f
Analog Electronics Laboratory Manual - 06ESL37
RE: W.K.T. VRE = VCC / 10 = 12 / 10 = 1.2V ------for biasing
IE IC = 4 mA
From the fig. We see that,
IERE = VRE
RE = 1.2 / (4 x 10-3 ) = 300
Therefore RE 330
RC: VCE = VCC / 2 = 6V ----- for Q point to be in active region.
Applying KVL to output loop
VCC –ICRC-VCE -VRE = 0
12 – 4 x 10-3 RC – 6 -1.2 = 0
Therefore RC = 1.2k
R1 & R2: From biasing circuit
VB = VBE+ VRE
= 0.7 + 1.2
VB = 1.9V
Assume 10 IB flows through R1 and 9 IB flows through R2.
W.K.T. IC = IB
4 x 10-3 = 100 IB
Therefore IB = 40 A
From the fig. we see that,
R1 = VCC – VB / 10 IB = 12 – 1.9 / (10 x 40 x 10-6 ) = 25.25k
Therefore R1 22k
R2 = VB / 9IB = 1.9 / ( 9 x 40 x 10-6 ) = 5.28k
Therefore R2 4.7k
CE, CC, CB : Let CB = CC = 0.1F
XCE = RE/10
Therefore f = 10 / (2 CE RE)
Let f = 100Hz and W.K.T RE = 330
Therefore CE = 10 / 2 f.RE = 48F
Therefore CE 47F.
Department of Electronics & Communication Engg. – CMRIT 24
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PROCEDURE:
1) To find Q point:
Connect the circuit without Vs and capacitors. Set Vcc= 12V. Measure dc
voltages at the base VB, collector Vc and VE with respect to ground
Determine VCE = VC – VE = --------- V
IC = (VCC-VC)/RC = -------- mA
Q point is Q(VCE,IC)
To check biasing conditions:
With VCC=12V; VCE should be VCC/2 = 6V
VRE should be VCC/10 = 1.2V
VBE = 0.6V
2) Connect the circuit of Fig(1)
3) Feed a sine wave of peak to peak amplitude about 40Mv from signal
generator.
4) Vary the input sine wave frequency from 10Hz to 1MHz in steps and
measure the output voltage VO of the amplifier. Input voltage Vi should
remain constant throughout the frequency range.
5) Tabulate the results.
6) Plot the graph of frequency f versus Gain in dB and determine the GBW
product
Procedure to measure input impedance Zi:
1) Connect the circuit of Fig(2).
2) Set the following:
DRB to zero.
Input sine wave amplitude of 40Mv
Input sine wave frequency to any mid band frequency.
3) Measure Vop-p.
4) Increase DRB till VO = Vop-p/2. The corresponding DRB value gives the
input impedance Zi.
Procedure to measure output impedance:
1) Connect as in Fig(3).
2) Set the following:
DRB to maximum value.
Input sine wave amplitude to 40mv.
Input sine wave frequency to any mid band frequency
3) Measure Vop-p.
4) Decrease DRB till Vo = Vop-p/2. The corresponding DRB value gives the
output impedance Zo.
Department of Electronics & Communication Engg. – CMRIT 25
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WAVEFORM:
Vin
0 t
V0
0 t
OBSERVATION
Vi = ---------------- mV
Freq.
(Hz)
Output
VoltageAV = V0 / Vi AV (dB) = 20log AV
100
.
.
.
1 M
FREQUENCY RESPONSE CURVE ( in Semilog )
Department of Electronics & Communication Engg. – CMRIT 26
Analog Electronics Laboratory Manual - 06ESL37
AV (db)
3db
f1 f2 f
Bandwidth = f2 – f1
RESULT:
Department of Electronics & Communication Engg. – CMRIT 27
Analog Electronics Laboratory Manual - 06ESL37
Ex.No:04 RC COUPLED AMPLIFIER – FET
AIM:
Design an RC coupled single stage FET amplifier and determine its gain
and frequency response, input and output impedances.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. FET BFW10 1 No
2. Capacitors 0.37 f 2 Nos.
100 µf 1 No
3. Resistors 2.2 M, 1 K, 330, 10 K Each 1 No
DC Supply, Signal Generator, CRO with Probe
CIRCUIT DIAGRAM:
To Determine Input Impedance:
47k
Vin Vout
To Determine Output Impedance:
Vin Vout
DESIGN:
Given VDD = 12V, IDss = 10 mA, VGS = - 2V, VP = -6 V
Department of Electronics & Communication Engg. – CMRIT 28
VOLTAGE SERIES FEEDBACK AMPLIFIER WITH / WITHOUT FEEDBACK
~
VOLTAGE SERIES FEEDBACK AMPLIFIER WITH / WITHOUT FEEDBACK
~DRB
0
C1=0.37µf
RD =1 K
BFW10D
GS
RS
330
C2=0.3µf
CS
100µfVINi
RL
10 K
VDD = 12V
RG
2.2M
Vo
Analog Electronics Laboratory Manual - 06ESL37
For proper biasing: VDD=12 V; VDS = 6 V;
VRS = VDD/10 = 1.2V
VGS = - 0.7 to -2V
To find RD :
Applying KVL to the output loop of the circuit
VDD = VDS + IDRD + VRS
12 = RD (5 x 10-3 ) + 6 + 1.2
RD = 960 1 k
ID = IDSS (1-VGS/ VP)2
= 10x10-3 (1- 2/6)2
= 4.4 mA 5mA
To find RS :
VRS = ISRS
RS = VRS/IS = 1.2 / 5x10 -3 240 270
Assume RS = 2 M
To find CS :
XS = 0.1 Rs = 27
XS = 1/2fCS
Let f = 50 Hz Therefore CS = 100µf
Let C1 = C2 = C
XD = 10 RD = 10K
XD = 1/2fC therefore C = 0.318µf
TABULAR COLUMN:
Vin = mV
Frequency (Hz)
V0 (V) AV AV (dB)
10
20
.
.
.
.
.
1M
FREQUENCY RESPONSE CURVE ( in Semilog )
AV (db)
Department of Electronics & Communication Engg. – CMRIT 29
Analog Electronics Laboratory Manual - 06ESL37
3db
f1 f2 f
Bandwidth = f2 – f1
WAVEFORM:
Vin
0 t
V0
0 t
RESULT:
Department of Electronics & Communication Engg. – CMRIT 30
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Ex.No:05 HARTLEY OSCILLATOR / COLPITT’S OSCILLATOR
AIM:
Design of Hartley/Colpitts oscillator for a given Radio frequency of f0
=100 KHz using BJT.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Transistor BC109 1 No
2. Capacitors0.1 f, 1000 pf 2 No
47µf, 0.0023 µf Each 1 No
3. Resistors 18K, 1.8K, 3.9K, 47001 K Pot
Each 1 No
4. Inductors 100 µH, 1mH, 5mH Each 1 No
DC Supply, CRO with Probe
THEORY :
Oscillators are devices, which generate oscillations. The frequency of
oscillations depends on the feedback network. Feedback may be of two types
namely positive and negative. In positive feedback, the feedback signal is
applied in phase with the input signal thus increasing it. In negative feedback,
the feedback signal is applied out of phase with the input thus reducing it. The
feedback used in oscillators is positive feedback. The oscillators work on the
principle of Barkhausen criteria. This states that for sustained oscillations
i) Loop gain Av must be equal to 1.
ii) The phase shift around the loop must be 0 deg of 360 deg.
Here Av is the gain of the amplifier and is the attenuation of the feedback
network. Consider the feedback network shown in the fig (1) below. Assume an
amplifier with input signal Vin. The output signal VO will be 180 deg out of phase
with Vin. So to get an in phase output, the feedback network provides 180-deg
phase shift. Therefore the output Vf from the feedback network can be made in
phase and equal in amplitude to Vin and Vin can be removed. Even then the
oscillations continue. Practical oscillations do not need any input signal to start
oscillations. They are self-starting due to thermally produced noise in resistors
and other components. Only one frequency (fo) of noise satisfies, Barkhausen
criteria and the circuit oscillates with that frequency. The magnitude of fo keeps
on increasing each time it goes around the loop. The amplification of fo is limited
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by circuit’s own non-linearities. Therefore to start oscillations Av > 1 and to
sustain it, the loop gain Av = 1.
Fig 1.
The feedback network used here consists of L and C. Consider the circuit
shown below fig 2. This circuit consists of L and C in parallel. The capacitor stores
energy in its electric field whenever there is voltage across it and the inductor
stores energy in its magnetic field whenever there is current through it. Initially
let us assume that the capacitor has charged to V volts. When S is closed c= 0.
When S is closed at t = t0 , capacitor starts charging through the inductor. Thus a
voltage gets built up across the inductor due to the change in current through it.
If the capacitor was changed with the polarity as shown in the fig 2 the current
starts flowing from the positive plate of the capacitor to the negativ4 plate of the
capacitor. As shown the voltage across the capacitor reduces during the
discharge time v reduces and I increases. At time t1 v will be 0 and I will be
maximum as c is fully discharged, the capacitor charges like sinusoidal
oscillations. Thus the circuit oscillates with the frequency
fo = 1/ 2LC
The Hartley oscillator consists of two inductors and a capacitor and Colpitts oscillator consists of two capacitors and an inductor.
The resonant frequency fo for Hartley oscillator is
fo =1/ 2 LeqC ------where Leq = L1 + L2.
Department of Electronics & Communication Engg. – CMRIT 32
L C
i
+-
S t = to
v
B
AvVin
Vf
Vo
Amplifier
Fig.2
Analog Electronics Laboratory Manual - 06ESL37
The resonant frequency fo for Colpitts oscillator is
fo = 1/ 2LCeq ------where Ceq = C1C2/(C1 + C2)
CIRCUIT DIAGRAM:
HARTLEY OSCILLATOR:
COLPITTS OSCILLATOR:
Department of Electronics & Communication Engg. – CMRIT 33
47 f
C = 0.0023 µf
GND
L1 = 100 µH L2 = 1mH
R2 CERE
3.9K470
BC109CB
CcR1
Vcc = 9 v
Rc
18K
1.8 K
0.1 f
0.1 f
VO
Variable1 K Pot
47 f
R2 CERE
3.9K470
BC109CB
CcR1
Vcc = 9 v
Rc
18K
1.8 K
0.1 f
0.1 f
VO
Variable1 K Pot
L = 5mH
GND
C2 = 1000pf C1 = 1000pf
Analog Electronics Laboratory Manual - 06ESL37
DESIGN:
Given VCC = 9V, IC = 2mA, = 50
RE: W.K.T. VRE = VCC / 10 = 9 / 10 = 0.9V ------for biasing
IE IC = 2 mA
From the fig. We see that,
IERE = VRE
RE = 0.9 / (2 x 10-3 ) = 450
Therefore RE 470
RC: VCE = VCC / 2 = 4.5V ----- for Q point to be in active region.
Applying KVL to output loop
VCC –ICRC-VCE -VRE = 0
9 – 2 x 10-3 RC – 4.5 -0.9 = 0
Therefore RC = 1.8k
R1 & R2: From biasing circuit
VB = VBE+ VRE
= 0.7 + 0.9
VB = 1.6V
Assume 10 IB flows through R1 and 9 IB flows through R2.
W.K.T. IC = IB
2 x 10-3 = 50 IB
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Therefore IB = 40 A
From the fig. we see that,
R1 = VCC – VB / 10 IB = 9 – 1.6 / (10 x 40 x 10-6 ) = 18.5k
Therefore R1 18k
R2 = VB / 9IB = 1.6 / ( 9 x 40 x 10-6 ) = 4.44k
Therefore R2 3.9k
CE, CC, CB : Let CB = CC = 0.1F
XCE = RE/10
Therefore f = 10 / (2 CE RE)
Let f = 100Hz and W.K.T RE = 470
Therefore CE = 10 / 2 f.RE = 34F
Therefore CE 47F.
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HARTLEY OSCILLATOR:
Attenuation = Vf/Vo = IXL1/IX L2 = XL1 / X L2 = 2 foL1/2foL2 = L1/L2
For sustained oscillations Av = 1 -------- Av = 1/ = L2/L1
For oscillations to start Av > 1 -----------Av > L2/L1
COLPITTS OSCILLATOR:
Attenuation = Vf / Vo = IXC1/IXC2 = XC1/ XC2 = (1/ 2foC1)/(1/2foC2) = C1/C2
For sustained oscillations Av = 1 ---------- Av = C1/C2
For oscillations to start Av > 1----------Av > C1/C2
DESIGN OF TANK CIRCUIT
Assume = fo = 100 KHz
HARTLEY OSCILLATOR
fo = 1/ (2 LeqC) ------where Leq = L1 + L2.
Assume L1 = 100 µH, L2 =1mH LEQ = fO =1/ (2 2*10-3 C) C = 0.0023 µf (Decade capacitance box)
COLPITTS OSCILLATOR
fO = 1/ (2LCeq ) ------where Ceq = (C1C2)/(C1 + C2)
Assume C1 = C2 = 1000 pF
Ceq =
fO = 1/ 2L * .05*10 - 6
L = 5 mH (Use decade inductance box)
Department of Electronics & Communication Engg. – CMRIT 36
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PROCEDURE:
1. Rig up the circuit as shown in the circuit diagram.
2. Before connecting the feedback network, check the circuit for biasing conditions i.e. check VCE, and VRE.
3. After connecting the feedback network. Check the output.
4. Check for the sinusoidal waveform at output. Note down the frequency of the output waveform and check for any deviation from the designed value of the frequency.
5. To get a sinusoidal waveform adjust 1K potentiometer.
6. DCB/DIB can be varied to vary the frequency of the output waveform.
TABULAR COLUMN
HARTLEY OSCILLATOR COLPITTS OSCILLATOR
SL NO C fo SL NO L fo
WAVEFORM:
Vo
0
t
T
frequency fo = 1/T
RESULT:
Department of Electronics & Communication Engg. – CMRIT 37
Analog Electronics Laboratory Manual - 06ESL37
Ex.No:06 CRYSTAL OSCILLATOR
AIM:
To design a crystal oscillator to oscillate at the specified crystal frequency.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Transistor BC109 1 No
2. Capacitors0.1 f 2 No
47µf 1 No
3. Resistors 18K, 1.8K, 3.9K, 4701 K Pot
Each 1 No
4. Crystal 2 MHz or 1.8 MHz 1 No
DC Supply, CRO with Probe
CIRCUIT DIAGRAM:
Department of Electronics & Communication Engg. – CMRIT 38
2 MHz
1.8 MHz
47 f
R2 CERE
3.9K470
BC109CB
CcR1
Vcc = 9 v
Rc
18K
1.8 K
0.1 f
0.1 f
VO
Variable1 K Pot
Analog Electronics Laboratory Manual - 06ESL37
DESIGN:Given VCC = 9V, IC = 2mA, = 50
RE: W.K.T. VRE = VCC / 10 = 9 / 10 = 0.9V ------for biasing
IE IC = 2 mA
From the fig. We see that,
IERE = VRE
RE = 0.9 / (2 x 10-3 ) = 450
Therefore RE 470
RC: VCE = VCC / 2 = 4.5V ----- for Q point to be in active region.
Applying KVL to output loop
VCC –ICRC-VCE -VRE = 0
9 – 2 x 10-3 RC – 4.5 -0.9 = 0
Therefore RC = 1.8k
R1 & R2: From biasing circuit
VB = VBE+ VRE
= 0.7 + 0.9
VB = 1.6V
Assume 10 IB flows through R1 and 9 IB flows through R2.
W.K.T. IC = IB
2 x 10-3 = 50 IB
Therefore IB = 40 A
From the fig. we see that,
R1 = VCC – VB / 10 IB = 9 – 1.6 / (10 x 40 x 10-6 ) = 18.5k
Therefore R1 18k
R2 = VB / 9IB = 1.6 / ( 9 x 40 x 10-6 ) = 4.44k
Therefore R2 3.9k
CE, CC, CB : Let CB = CC = 0.1F
XCE = RE/10
Therefore f = 10 / (2 CE RE)
Let f = 100Hz and W.K.T RE = 470
Therefore CE = 10 / 2 f.RE = 34F
Therefore CE 47F.
Department of Electronics & Communication Engg. – CMRIT 39
Analog Electronics Laboratory Manual - 06ESL37
PROCEDURE:1. Rig up the circuit as shown in the circuit diagram.
2. Before connecting the feedback network, check the circuit for biasing conditions i.e. check VCE, and VRE.
3. After connecting the feedback network. Check the output.
4. Check for the sinusoidal waveform at output. Note down the frequency of the output waveform and check for any deviation from the designed value of the frequency.
5. To get a sinusoidal waveform adjust 1K potentiometer.
WAVEFORM:
Vo
0
t
T
frequency fo = 1/T
RESULT:
Department of Electronics & Communication Engg. – CMRIT 40
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Ex.No:07 RC PHASE SHIFT OSCILLATOR
AIM:
Design a circuit, which generates repetitive waveform (Sinusoidal signal)
of frequency 7 KHz.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Transistor SL100 1 No
2. Capacitors 0.02 f 3 NoS.
0.1 f 2 Nos.
47µf 1 No
3. Resistors 22K, 4.7K, 1.2K, 3301 K Pot
Each 1 No
470 3 Nos.
DC Supply, CRO with Probe
THEORY:
RC Phase shift oscillator consists of a single transistor amplifier and a
RCphase shift network. The Phase shift network consists of three RC sections.
Here a fraction of the output of the amplifier is passed through a phase shift
network before feeding back to the input. The phase shift in each section is 600
so that the total phase shift is 1800.Another 1800 phase shift is provided by the
transistor amplifier and therefore the total phase shift of the oscillator is 360 0
.The frequency of oscillations is given by
fo = 1 / [26(RC)]
Let us consider a RC circuit..
Let I be the current flowing through both R and C. Then using I as the
reference vector,Vo is in phase with I while Vc ,the voltage across the capacitor
is 900 behind as shown in the figure.
Vi is the sum of Vo and Vc.Hence Vc is degrees ahead of Vi and represents a
phase shift of degrees
Vo = IR, Vc =IXc
Tan =Vc/Vo =Ixc/IR = Xc/R = 1/(2fCR)
Therefore f = 1/(2fCR Tan )
If there are 3 sections each must give approximately 600
i.e. = 600 Tan =3 =1.73
f= 1/(2CR3)
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The above phase discussion ignored the additional current I that flows
through C for other sections, so that Vc is actually larger than the value
indicated,which means f is smaller.
More accurately f = 1/26(RC)
CIRCUIT DIAGRAM:
DESIGN:
Given VCC = 12V, IC = 4mA, = 100.
RE: W.K.T. VRE = VCC / 10 = 12 / 10 = 1.2V ------for biasing
IE IC = 4 mA
From the fig. We see that,
IERE = VRE
RE = 1.2 / (4 x 10-3 ) = 300
Therefore RE 330
RC: VCE = VCC / 2 = 6V ----- for Q point to be in active region.
Applying KVL to output loop
VCC –ICRC-VCE -VRE = 0
12 – 4 x 10-3 RC – 6 -1.2 = 0
Therefore RC = 1.2k
R1 & R2: From biasing circuit
VB = VBE+ VRE
= 0.7 + 1.2
Department of Electronics & Communication Engg. – CMRIT 42
Q11
23
R 4700.1u
1k
VCC(12V)
A B C
R1=22K
R2=4.7 K
RC=1.2K
RE=330 CE=47µf
Cc
CC=0.1µf
SL100 0.02µf
C
0.02µf
C
0.02µf
C
R 470 R 470
D
Analog Electronics Laboratory Manual - 06ESL37
VB = 1.9V
Assume 10 IB flows through R1 and 9 IB flows through R2.
W.K.T. IC = IB
4 x 10-3 = 100 IB
Therefore IB = 40 A
From the fig. we see that,
R1 = VCC – VB / 10 IB = 12 – 1.9 / (10 x 40 x 10-6 ) = 25.25k
Therefore R1 22k
R2 = VB / 9IB = 1.9 / ( 9 x 40 x 10-6 ) = 5.28k
Therefore R2 4.7k
CE, CC, CB : Let CB = CC = 0.1F
XCE = RE/10
Therefore f = 10 / (2 CE RE)
Let f = 100Hz and W.K.T RE = 330
Therefore CE = 10 / 2 f.RE = 48F
Therefore CE 47F.
DESIGN OF TANK CIRCUIT:
We know that f=1/(2 RC6)
Given fO = 7 KHz
Assume C = 0.02 F
R = 1/(2 x 0.02 x 10-6 x 7 x 10+3 x 6) =527 470
PROCEDURE:
1. Make the connections as shown in the circuit diagram.
2. Check the circuit for biasing.
3. Adjust the 1k potentiometer to get sinusoidal waveform at the output.
4. To measure the phase shift
Method 1:
Connect the channel 1 of the CRO to point D and channel 2 to point A.
We will get two sine waves with a phase difference
Measure the difference by converting the time into angle.
Method 2:
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a] Connect channel 1 to point D and channel 2 to point A.
Press the XY knob and measure the phase shift.
=Sin-1 (a/b) (approx.=600)
b] Connect channel 2 to point B the graph is as shown
= Sin-1(a/b)
Phase angle =1800- (approx. = 1200)
C] Connect channel 2 to point C
The transfer function will be almost a straight line and =00 and
therefore phase angle =1800 - 00 = 1800
WAVEFORM:
0 t
f = 1 / T
RESULT:
Department of Electronics & Communication Engg. – CMRIT 44
b
a
b
a
Analog Electronics Laboratory Manual - 06ESL37
Ex.No:08 VOLTAGE SERIES FEEDBACK AMPLIFIER USING BJT
AIM:
To design and test a two stage voltage series feedback amplifier using BJT
and to determine gain, frequency response, input and output impedance with
and without feedback.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Transistor SL100 2 Nos.
2. Capacitors 0.47 f 3 Nos
10µf 2 Nos
3. Resistors 12K, 2.7K, 2.2K, 560 Each 2 No
4.7 K, 100 Each 1 No
4. Variable Resistor 1K Pot 1 No.
DC Supply, Signal Generator, CRO with Probe
THEORY:
The high gain amplifier is widely used in analog circuit design and will
serve as the step to the next higher level of complex analog systems. The
philosophy behind the high gain amplifier is based on the concept of feedback. In
analog circuits we must be able to precisely define transfer function. A familiar
representation of this concept is illustrated in the block diagram below:
xs + xi A x0
_
xf
Here x voltage or current
A High Gain Amplifier
Feedback Network
xs Input signal (source)
xi Input signal to amplifier
xf Feedback signal
The overall gain of the amplifier with feedback is given by
Af = x0 / xs = A / (1 + A)
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The high gain amplifier is defined by
A = x0 / xi
The gains defined above may be current gain or voltage gain.
In the circuit shown below, the feedback signal is the voltage V f across R1
and the sampled signal is the output voltage V0 across R. It is called voltage
series feedback amplifier because a part of the output voltage is fed back in
series with the input.
CIRCUIT DIAGRAM:
WITHOUT FEEDBACK
WITH FEEDBACK
Department of Electronics & Communication Engg. – CMRIT 46
10 K
10 fR2
SL100
CcR1
CE
RE
B
Vo
Rc12K
2.7K
2.2 K
560
0.47 f
R2
SL100
CcR1
CB
Vcc = 12 v
CE
RE
Rc12K
2.7K
2.2 K
560
0.47 f0.47 f
Vcc = 12 v
10 f
~Vs
10 fR2
SL100
CcR1
CE
RE
B
Vo
Rc12K
2.7K
2.2 K
560
0.47 f
R2
SL100
CB
CcR1
CERE
Rc
12K
2.7K
2.2 K
560
0.47 f
0.47 f
100 RF
R
~Vs
Analog Electronics Laboratory Manual - 06ESL37
To Determine Input Impedance
47k
Vin Vout
To Determine Output Impedance
Vin Vout
DESIGN:
Given VCC = 12V, IC = 2mA, = 25.
RE: W.K.T. VRE = VCC / 10 = 12 / 10 = 1.2V ------for biasing
IE IC = 2 mA
From the fig. We see that,
IERE = VRE
RE = 1.2 / (2 x 10-3 )
RE 560
RC: VCE = VCC / 2 = 6V ----- for Q point to be in active region.
Applying KVL to output loop
VCC –ICRC-VCE -VRE = 0
12 – 2 x 10-3 RC – 6 -1.2 = 0
Therefore RC = 2.2k
R1 & R2: From biasing circuit
VB = VBE+ VRE
= 0.7 + 1.2
VB = 1.9V
Assume 10 IB flows through R1 and 9 IB flows through R2.
W.K.T. IC = IB
2 x 10-3 = 100 IB
Therefore IB = 20 A
From the fig. we see that,
R1 = VCC – VB / 10 IB = 12 – 1.9 / (10 x 20 x 10-6 )
Therefore R1 12k
Department of Electronics & Communication Engg. – CMRIT 47
VOLTAGE SERIES FEEDBACK AMPLIFIER WITH / WITHOUT FEEDBACK
~
VOLTAGE SERIES FEEDBACK AMPLIFIER WITH / WITHOUT FEEDBACK
~DRB
Analog Electronics Laboratory Manual - 06ESL37
R2 = VB / 9IB = 1.9 / ( 9 x 20 x 10-6 )
R2 2.7k
CE, CC, CB : Let CB = CC = 0.1F
XCE = RE/10
Therefore f = 10 / (2 CE RE)
Let f = 100Hz and W.K.T RE = 560
Therefore CE = 10 / 2 f.RE = 10f
Therefore CE 10f.
DESIGN FEED BACK CIRCUIT
Let β = 0.02
β = Rf/ Rf + R
Rf = β R / 1 – β
Let R = 4.7 K
Therefore Rf = 100
PROCEDURE:
1. Rig the circuit as shown in the fig.
2. Check the circuit for biasing i.e. check VDD, VDS and VRS.
3. Give a sinusoidal input of 10kHz from signal generator. Adjust the
amplitude of this sine wave such that the output doesn’t get clipped.
4. Observe the output waveform on the CRO.
5. Measure the output voltage using AC milli voltmeter.
6. Measure the output voltage for different frequencies of the input and
tabulate the readings as shown in the tabular column.
7. Plot the graph of gain vs frequency on a semilog graph sheet as shown
in the fig.
8. To measure input impedance connect a resistor of 47k in series with
the signal generator.
9. Measure the voltage at the input point (VS) and at the point after the
resistor (Vin).
10.Current through the resistor is given by the expression
I = ( VS – Vin ) / 47k
11.Input impedance is given by Zin = Vin / 47k
12.To measure output impedance connect a DRB in parallel with the
output.
13.Adjust all the knobs of the DRB to maximum.
14.Start reducing the resistance in the DRB from a large value until the
output reduces to half.
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15.The resistance in the DRB is the output impedance.
TABULAR COLUMN:
Without FeedbackVin = constant
Frequency (Hz)
V0 (V) AV AV (dB)
10
20
.
.
.
.
.
1M
With FeedbackVin = constant
Frequency (Hz)
V0 (V) AV AV (dB)
10
20
.
.
.
.
.
.
1M
EXPECTED GRAPH:
AV
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Analog Electronics Laboratory Manual - 06ESL37
Without feedback
With feedback
0 f
WAVEFORM:
Vin
0 t
V0
0 t
RESULT:
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Ex.No:09THEVININ’S THEOREM AND
MAXIMUM POWER TRANSFER THEOREM
AIM: To State and verify the thevenin’s theorem for the given circuit. COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Resistors 1 K 4 Nos.
DC Supply, Multimeter, Ammeter (0-10)mA
THEORY:
Any Linear, bilateral network containing energy sources and impedances
can be replaced with equivalent circuit consisting of a voltage source in series
with an impedance.
The Value of voltage source is open circuit voltage between terminals of a
network and value of impedance is the impedance measured between the two
terminal of a network with all energy sources eliminated.
Circuit diagram:
RL
+
R31 k
R11k R2
-
B
1k
FIG 1
A
5v 1k
R1
Vo
1k R2
A
A
0-10mA
IL
FIG 2
1k
B
+
1 k
1k
-5v
-
R3 + RL
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Vo-
+
-
FIG 3
+
-
0-10mA
I
-
A
+
B
R11k R2
5v
A+
1k
1k
R3
Analog Electronics Laboratory Manual - 06ESL37
Procedure:
1. Connection are made as shown in the fig(2).
2. Supply voltage is adjusted to 5v and the ammeter reading IL is noted down.
3. Open circuit the terminal A & B , Voltmeter reading Vo is measure which is the thevenin’s voltage. Vo=VTH= ___________Volts .
4. To find the Thevenin’s impedance, connections are made as shown in the fig (3)
5. The reading of voltmeter V and ammeter I are noted . the thevenin’s Impedance
ZTH=V/I W
ZTH=_____________ W
6. Thevenin’s equivalent circuit connection are made as shown in the fig (4)
7. The supply voltage is set to Vth as measured above.
8. The ammeter reading Ith is noted.
If Ith=IL, Thevenin’s theorem is verified.
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0-10mA
RL
1kVTH
ZTHA
+
Ith
_
Analog Electronics Laboratory Manual - 06ESL37
(2) MAXIMUM POWER TRANSFER THEOREM:
Aim: (i) To state and verify maximum power transfer theorem.
(ii) To determine maximum power and the value of RL for Maximum power
transfer.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Resistors 1 K 1 No.
DC Supply, DRB, Multimeter, Ammeter (0-10)mA
Circuit diagram:
I10v
Rs0-10mA
-A
_
-+
1k
VR l
1 0 k p o t
+
Circuit for measuring source resistance:
Rs
A
1k
-0-10mA
Is
+
_-
Vs+
+
10v
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Procedure:1. Connection are made as shown in the fig(i).
2. Supply voltage V is set to 10V, the potentiometer RL is kept at maximum.
3. The readings of voltmeter (V) and ammeter (I) are noted down in the table.
4. RL is decreased in steps and at each steps readings of V and I are tabulated in the table.
5. A graph of RL versus power is plotted, the maximum power Pmax and value of RL for maximum power transfer are noted from graph PMAX
=_______W, RL = .
6. To measure source resistance the connection are made as shown in the fig (2)
7. Supply is set to 10V, the ammeter reading I and voltmeter reading are noted down.
The source resistance RS=V/I =__________
If RS = RL, MPT Theorem is verified
V (volts) I mAmps P = VI in W RL= V/I
RESULT :
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RL, RL, for PMAX
PMAX
Power , Watts
Analog Electronics Laboratory Manual - 06ESL37
Ex.No: 10 SERIES AND PARALLEL RESONANCE SERIES RESONANCE CIRCUIT
Aim : To obtain the frequency response of an RLC series circuit and hence to determine
a) Resonance frequency fob) Band width ,Upper and Lower half power frequency c) Q-factor.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Resistors 100 1 No.
2. Capacitor 0.22µf 1 No.
3. Inductor 1 mH 1 No.
Signal generator, Multimeter
Circuit diagram:
DESIGN:
fo = 1/2LC Let L = 1mHC = 1/42Lfo2
C = 0.22μfR = 100Find fo
Procedure:1. Connections are made as shown in the circuit diagram.2. AC Supply is switched on. oscillator output voltage is adjusted to about
maximum i.e 10V P-P3. The frequency is gradually varied from zero hertz and for different value
of “ f”, voltage is noted down. The results are tabulated in the tabular column.
4. Frequency response i.e a graph of frequency versus voltage is drawn.
5. From the graph , resonant frequency “fo” is noted down at which voltage is maximum(Vo).
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L
C
R VO
Analog Electronics Laboratory Manual - 06ESL37
6. Lower half power frequency “f1” and upper half power frequency “f2” are noted corresponding to a voltage of Vo/ 2
Band width=f2-f1=_____________ hertz
7. The Q-factor =fo/f2-f1
Tabular column
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f in hz V in VOLTS
Analog Electronics Laboratory Manual - 06ESL37
FREQUENCY RESPONSE CURVE ( in Semilog )
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0
BW
f1 f0 f2 f, Hz
VO
VOmax
VOmax/2
Analog Electronics Laboratory Manual - 06ESL37
PARALLEL RESONANCE CIRCUIT:
Aim : To obtain the frequency response of an RLC series circuit and hence to determine
a) Resonance frequency fob) Band width ,upper and lower half power frequencyc) Q-factor.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Resistors 100 1 No.
2. Capacitor 0.22µf 1 No.
3. Inductor 1 mH 1 No.
Signal generator, Multimeter
Circuit diagram:
Frequency response
Vo
Vomin x 2
Vomin
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f1 fO f2 fin Hz
BW
0
L C
R VO
Analog Electronics Laboratory Manual - 06ESL37
Procedure:1. Connections are made as shown in the circuit diagram.2. AC Supply is switched on. oscillator output voltage is adjusted to about
maximum i.e 10V P-P3. The frequency is gradually varied from zero hertz and for different value
of “ f”, voltage is noted down. The results are tabulated in the tabular column.
4. Frequency response i.e a graph of frequency versus voltage is drawn.5. From the graph , resonant frequency “fo” is noted down at which voltage
is minimum (Vo).6. Lower half power frequency “f1” and upper half power frequency “f2” are
noted corresponding to a voltage of VOmin x 2.a. Band width = f2 - f1=_____________ Hz
7. The Q-factor =fo/f2-f1
RESULT:
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Ex.No: 11 DARLINGTON EMITTER FOLLOWER
AIM:
To design and test a Darlington emitter follower circuit with and without
boot strapping and determine the gain, input and output impedance for both the
circuits.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. Transistor SL100 2 Nos.
2. Capacitors10 f 1 No
0.47µf 2 Nos.
3. Resistors 1 M, 2.2 M, 1.5 K, 10 K, 47K Each 1 No
DC Supply, CRO with Probe, Signal generator, AC millivoltmeter
THEORY:
Normally transistors are used as amplifiers. But there are some
applications in which, matching of impedance is required between two circuits
without any gain or attenuation. In such applications emitter followers are used.
Emitter followers have large input impedance and small output impedance.
Darlington emitter follower has two transistors connected in cascade such that
the emitter of first transistor is connected to the base of second transistor. The
voltage gain of the darlington emitter follower is close to unity. The major
drawback of this circuit is that the second transistor amplifies leakage current of
the first transistor and overall leakage current becomes high. The output is
observed at the emitter terminal of the second transistor. Hence it is called an
emitter follower.
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CIRCUIT DIAGRAM:
Darlington emitter follower without bootstrapping
Darlington emitter follower with bootstrapping
DESIGN:
Given IC = 4mA, VCC = 12V, VBE = 0.6V, 1 = 2 = 100
To find RE:
Applying KVL to the output loop of the second transistor, we get
VCC = VCE + VRE
Therefore VRE = VCC – VCE = 12 – 6
Therefore VRE = 6V
W.K.T RE = VRE / IE2
Here IE2 = IC2
Therefore RE = 6 / 4 x 10-3
RE = 1.5k
To find R1 & R2:
From the circuit we have
Department of Electronics & Communication Engg. – CMRIT 61
QSL100
RE
SL100
Vin
Vcc = 12V
Q1
Vo
R1
Cb = 0.47µf
1 M
R2
2.2 M
1.5 K
CE = 0.47µf
CE = 0.47µf
R3
Analog Electronics Laboratory Manual - 06ESL37
VA = VBE1 + VBE2 + VRE
= 0.6 + 0.6 + 6 = 7.2V
W.K.T. IC = IB
Therefore IB = (4 x 10-3)/ 100 = 40 A
Let 10IB be the current through R1 and 9IB be the current through R2.
From the fig. we see that
R1 = (VCC – VA) / 10IB
Therefore R1 = 12K
From the fig. R2 = VA / 9IB
Therefore R2 = 20 K 22K
W.K.T. CC = 10 / XRE = 10 / ( 2..f.RE)
Assume f = 50Hz
Therefore CC = 21.2F 47 F
W.K.T. Cb = 10 / XRB = 10 / ( 2..f.RB ) where RB = R1 || R2 = 7.5k
Therefore Cb = 4.2F 4.7F
Chose R3 = 10 K, CB = 10µf for bootstrapping
PROCEDURE:
1. Rig up the circuit as shown in the fig.
2. Check the circuit for biasing, i.e. check VCE, VCC and VRE.
3. Give a sinusoidal input signal of 1KHz from a signal generator.
4. Set the input signal to a value such that the output doesn’t get clipped.
5. For different frequencies of the input signal, read the output on the voltmeter and verify that the gain is 1.
6. To measure input impedance, connect a resistor of 47k in series with the signal generator.
7. Measure the voltage at the input point (VS) and at the point after the resistor (VIN).
8. Current through the resistor is given by the expression I = (VS - VIN) / 47K.
9. Input impedance is given by ZIN = VIN / 47 K
10.To measure output impedance, connect a DRB in parallel with the output.
11.Adjust all the knobs of the DRB to maximum.
12.Start reducing the resistance in the DRB from a large value until the output reduces to half.
13.The resistance in the DRB is the output impedance.TABULAR COLUMN:
VIN = __________ constant
Frequency(Hz)
V0 (V) AV AV (dB)
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WAVEFORM:
Vin
Vin 0 t
V0
0 t Vin
RESULT:
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Ex.No: 12 TRANSFORMERLESS CLASS-B PUSH PULL POWER AMPLIFIER
Aim: Testing of a transformer less class-B push pull power amplifier and determination of its conversion efficiency.
COMPONENTS REQUIRED:
Sl. No. Components Details Specification Qty
1. TransistorSL100 1 No.
SK100 1 No.
2. Diode BY127 2 Nos.
3. Capacitors47 f 2 Nos.
470 µf 1 No.
4. Resistors220 2 No
DRB 1 No
DC Supply, CRO with Probe, Signal generator, AC millivoltmeter
Theory: In class B operation, to obtain output for the full cycle of signal, it is necessary to use two transistors and have each conduct on opposite half cycle, the combined operation providing a full cycle of output signal. Since one part of the circuit pushes the signal high during one half cycle and the other part pulls the signal low during the other half cycle, the circuit is referred to as a push pull circuit.
Circuit diagram:
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DESIGN:
Given Vcc =2.5V; RL= 10 Ω; IDC = 3mA
To Find R1 & R2:Applying KVL at the input circuit; We get ; Vcc = 2VR1 + 1.4Therefore; VR1 = 0.55V; VR1 =IDCR1 = 0.55V; R1 = 183Ω.Choose; R1 = R2 = 220Ω.
To Find Ci :Input coupling capacitor is given by, Xci >Zieff/10 >1.1K/10Xci > 1/2πfCi ;Ci >28μF; Choose Ci = 47μF
To Find CO:Output coupling capacitor is given by, Xco = 10Xco > 1/2πfCoCo > 318μF; Choose; Co = 470μFPoac=Vo2/8RL Pidc=VccIdc
Calculate circuit efficiency, η = Po (ac)/Pi(dc) = (π/4)Vo/Vcc = ?
Procedure:1. Connect the circuit as per the circuit diagram.2. Set VI = 3V, using the signal generator.3. Keeping the input voltage constant, vary the load resistor and note down
the readings of the ammeter and peak to peak output voltage.4. Calculate PDC, PAC and % efficiency η.5. Draw the plot of resistance versus output power.
Tabulation
Vi = ----------------
RL () VO (v) IDC(mA) PAC PDC %
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Resistance(Ω)
Po (watts)
Analog Electronics Laboratory Manual - 06ESL37
Result:
BIBLIOGRAPHY
1. “Electronic devices and circuit theory”, Robert L.Boylestad and
Louis Nashelsky.
2. “Integrated electronics”, Jacob Millman and Christos C Halkias.
3. “Electronic devices and circuits”, David A. Bell.
4. “Electronic devices and circuits”, G.K.Mittal.
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VIVA-VOCE QUESTIONS
1. What are conductors, insulators, and semi-conductors? Give egs.2. Name different types of semiconductors.3. What are intrinsic semiconductors and extrinsic semiconductors?4. How do you get P-wpe and N-type semiconductors?5. What is doping? Name different levels of doping.6. Name different types of Dopants. .7. What do you understand by Donor and acceptor atoms?8. What is the other name for p-type and N-type semiconductors?9. What are majority carriers and minority carriers?
10. What is the effect of temperature on semiconductors?11. What is drift current? .12. What is depletion region or space charge region?13. What is junction potential or potential barrier in PN junctioI).?14. What is a diode? Name different types of diodes and name its applications 15. What is biasing? Name different types w.r.t. Diode biasing16. How does a diode behave in its forward and reverse biased conditions?17. What is static and dyriantic resistance of diode?18. Why the current in the fo~ard biased diode takes exponential path?19. What do you understand 1?y AvaJanche breakdown and zener breakdown?20. Why diode is called unidirectional device.21. What is PIV of a diode22. What is knee voltage or cut-in voltage?23. What do you mean by transition capacitance or space charge capacitor?24. What do you mean by diffusion capacitance or storage capacitance?25. What is a transistor? Why is it called so? .26. Name different types, of transistors?27. Name different configurations in which the transistor is operated28. Mention the applications of transistor. Explain how transistor is used as switch 29. What is transistor biasing? Why is it necessary?30. What are the three different regions in which the transistor works?31. Why trmisistor is called current controlled device?32. What is FET? Why it is called so?33. What are the parameters ofFET?34. What are the characteristics of FET?35. Why FET is known as voltage controlled device?36. What are the differences between BJT and FET?37. Mention applications ofFET. What is pinch offvQltage, VGS(ofJ) and lDss38. What is an amplifier? What is the need for an amplifier circuit?39. How do you classify amplifiers? ,40. What is faithful amplification? How do you achieve this?41. What is coupling? Name different type.s of coupling42. What is operating point or quiescent point?43. What do you mean by frequency response of an amplifier?44. What are gain, Bandwidth, lower cutoff frequency and upper cutoff frequency?45. What is the figure of merit of an amplifier circuit?46. What are the advantages of RC coupled amplifier?47. Why a 3db point is taken to calculate Bandwidth?48. What is semi-log graph sheet? Why it is used to plot frequency response?49. How do you test a diode, transistor, FET?50. How do you identify the tenninals of Diode, Transistor& FET? Mention the type
number of the devices used in your lab.
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51. Describe the operation ofNPN transistor. Define reverse saturation current.52. Explain Doping w.r.t. Three regions of transistor53. Explain the terms hie/hib, hoelhob, hre/hrb, hre/hfb.54. Explain thermal run-.taway. How it can'be prevented.55. Define FET parameters and write the relation between them.56. What are Drain Characteristics and transfer characteristics?57. Explain the construction and working of FET58. What is feedback? Name different types.59. What is the effect of negative feedback on the characteristics of an amplifier?60. Why common collector amplifier is known as emitter follower circuit?61. What is the application of emitter follower ckt?62. What is cascading and cascoding? Why do you cascade the amplifier ckts.?63. How do you determine the value of capacitor?64. Write down the diode current equation.65. Write symbols of various passive and active components66. How do you determine th~value of resistor by colour code method?67. What is tolerance and power rating of resistor?68. Name different types of resistors.69. How do you c1assify resistors?70. Name different types of capacitors..71. What are clipping circuits? Classify them.72. Mention the application of clipping circuits.73. What are clamping circuits? Classify them74. What is the other name of clamping circuits?75. Mention the applications of clamping circuits.76. 'What is Darlington emitter follower circuit?77. Can we increase the number of transistors in Darlington emitter follower circuit?
Justify your answer.78. What is the different between Darlington emitter follower circuit & Voltage
follower circuit using Op-Amp. Which is better.79. Name different types of Emitter follower circuits.80. What is an Oscillator? Classify them.81. What ar~ The Blocks, which fonns an Oscillator circuits?82. What are damped & Un-damped Oscillations?83. What are Barkhausen's criteria?84. What type of oscillator has got frequency stability?85. What is the disadvantage of Hartley & Colpiit's Oscillator?86. Why RC tank Circuit Oscillator is used for AF range?87. Why LC tank Circuit Oscillator is used for RF range?88. What type of feedback is used in Oscillator circuit?89. In a Transistor type No. SL 100 and in Diode BY 127, what does SL and BY stands
for90. Classify Amplifiers based on: operating point selection.91. What is the efficiency of Class B push pull amplifier?92. What is the drawback of Class B Push pull Amplifier? How it is eliminated.93. What is the advantage of having complimentary symmetry push pull amplifier?94. What is Bootstrapping? What is the advantage of bootstrapping?95. State Thevenin's Theorem and Max.power transfer theorem.96. What is the figure of merit of resonance circuit?97. What is the application of resonant circuit?98. What is a rectifier? Classify.99. What is the efficiency of half wave and full wave rectifier?
100. What is the advantage of Bridge rectifier of Centre tapped type FWR
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101. What is the disadvantage of Bridge rectifier?102. What is a filter?103. Name different types of filter ckts.104. Which type of filter is used in day to day application and why?105. What is ripple and ripple factor? .106. What is the theoretical value of ripple for Half Wave and .Full wave rectifier?107. What is need for rectifier ckts.108. Why a step down transformer is used at the input of Rectifier ckt.109. What is TUF? .110. What is regulation w.r.t rectifier? And how it is calculated?111. What is figure of merit of Rectifier ckt.
Department of Electronics & Communication Engg. – CMRIT 69