AB09
Rectifier Circuit
Learning Material
Ver.1.1
An ISO 9001:2008 company
Scientech Technologies Pvt. Ltd.
94, Electronic Complex, Pardesipura, Indore - 452 010 India,
+ 91-731 4211100, : info@scientech.bz , : www.ScientechWorld.com
AB09
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AB09
AB09
Rectifier Circuit
Table of Contents
1.
Introduction
4
2.
Theory
6
3.
Experiments
•
Experiment 1
To study Half wave Rectifier
11
•
Experiment 2
To study Center tap Full wave Rectifier
13
•
Experiment 3
To study Bridge Rectifier
15
4.
Data Sheet
17
5.
Warranty
18
6.
List of Accessories
18
RoHS Compliance
Scientech Products are RoHS Complied.
RoHS Directive concerns with the restrictive use of Hazardous substances (Pb,
Cd, Cr, Hg, Br compounds) in electric and electronic equipments.
Scientech products are “Lead Free” and “Environment Friendly”.
It is mandatory that service engineers use lead free solder wire and use the
soldering irons upto (25 W) that reach a temperature of 450°C at the tip as the
melting temperature of the unleaded solder is higher than the leaded solder.
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AB09
Introduction
AB09 is a compact, ready to use Rectifier Circuit experiment board. This board is
useful for students to understand half wave, Full wave Center tap and Full wave
Bridge Rectifier circuits and their working. It can be used as stand alone unit with
external DC power supply or can be used with Scientech Analog Lab ST2612 which
has built in DC power supply, AC power supply, function generator, modulation
generator, continuity tester, toggle switches and potentiometer.
List of Boards:
Model
Name
AB01
AB02
AB03
AB04
AB05
AB06
AB07
AB08
AB10
AB11
AB12
AB13
AB14
AB15
AB16
AB17
AB18
AB19
AB20
AB21
AB22
AB23
AB24
AB25
AB26
AB27
AB29
AB30
AB31
AB32
AB33
AB35
AB37
AB39
AB41
Diode characteristics (Si, Zener, LED)
Transistor characteristics (CB NPN)
Transistor characteristics (CB PNP)
Transistor characteristics (CE NPN)
Transistor characteristics (CE PNP)
Transistor characteristics (CC NPN)
Transistor characteristics (CC PNP)
FET characteristics
Wheatstone bridge
Maxwell’s Bridge
De Sauty’s Bridge
Schering Bridge
Darlington Pair
Common Emitter Amplifier
Common Collector Amplifier
Common Base Amplifier
RC-Coupled Amplifier
Cascode Amplifier
Direct Coupled Amplifier
Class A Amplifier
Class B Amplifier (push pull emitter follower)
Class C Tuned Amplifier
Transformer Coupled Amplifier
Phase Locked Loop (FM Demodulator & Frequency Divider /
Multiplier)
FET Amplifier
Voltage Controlled Oscillator
F-V and V-F Converter
V-I and I-V Converter
Zener Voltage Regulator
Transistor Series Voltage Regulator
Transistor Shunt Voltage Regulator
DC Ammeter
DC Ammeter (0-2mA)
Instrumentation Amplifier
Differential Amplifier (Transistorized)
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AB09
AB42
AB43
AB44
AB45
AB49
AB51
AB52
AB54
AB56
AB57
AB58
AB59
AB64
AB66
AB67
AB68
AB80
AB82
AB83
AB84
AB85
AB88
AB89
AB90
AB91
AB92
AB93
AB96
AB97
AB101
AB102
AB106
Operational Amplifier (Inverting / Non-inverting / Differentiator)
Operational Amplifier (Adder/Scalar)
Operational Amplifier (Integrator/ Differentiator)
Schmitt Trigger and Comparator
K Derived Filter
Active filters (Low Pass and High Pass)
Active Band Pass Filter
Tschebyscheff Filter
Fiber Optic Analog Link
Owen’s Bridge
Anderson’s Bridge
Maxwell’s Inductance Bridge
RC – Coupled Amplifier with Feedback
Wien Bridge Oscillators
Colpitt Oscillator
Hartley Oscillator
RLC Series and RLC Parallel Resonance
Thevenin’s and Maximum Power Transfer Theorem
Reciprocity and Superposition Theorem
Tellegen’s Theorem
Norton’s theorem
Diode Clipper
Diode Clampers
Two port network parameter
Optical Transducer (Photovoltaic cell)
Optical Transducer (Photoconductive cell/LDR)
Optical Transducer (Phototransistor)
Temperature Transducer (RTD & IC335)
Temperature Transducer (Thermocouple)
DSB Modulator and Demodulator
SSB Modulator and Demodulator
FM Modulator and Demodulator
and many more…………
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Theory
Rectifier is an electronic device that converts alternating current into direct current. A
rectifier changes AC into DC by eliminating the negative half-cycles of the alternating
voltage, so it provides a one way path for electric current i.e. conduction takes place
in one direction only. It is in this way that a rectifier converts an alternating current
into unidirectional current.
Rectifier can be classified into two categories:
1.
Half-wave rectifier
2.
Full-wave rectifier
Half wave rectifier conducts only on positive half cycles of input voltages i.e. it uses
one half cycles of AC input voltages to produce DC output .On the other hand, a fullwave rectifier conducts on both the half cycles of input AC voltage to produce DC
output. So a full wave rectifier circuit can supply more DC output more than the
equivalent half-wave rectifier.
Half wave Rectifier:
A half wave rectifier employs a single diode as shown in figure 1.
Figure 1
During the positive half cycle of the input voltage diode conducts, so a short circuit
equivalence of the ideal diode will result in an output signal which is an exact replica
of the input signal. For the negative half cycle of the applied signal diode is in the off
state with an open circuit equivalent, which results in the absence of a path for the
charge to flow, so a zero voltage appears for the negative half cycle of input voltage.
Vdc = .318 Vm
Limitation of Half wave Rectifier:
The AC power delivers only half the time, hence output is low.
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Full Wave Rectifier:
The DC level obtained from a sinusoidal input can be improved to 100%
process called full wave rectification.
using a
A full wave rectifier can be classified into two categories:
a.
Center-Tapped full wave rectifier
b.
Full-wave Bridge Network
Center-Tapped Full wave Rectifier:
Center-Tapped full wave rectifier requires two diodes and a center-tapped
transformer. The circuit diagram is shown in figure 2.
Figure 2
During the positive portion of input signal diode D1 conducts so there exists a short
circuit equivalent across D1 and open circuit equivalent across D2 and the output
voltage appears across load resistor RL. During the negative portion of input voltage
the roles of the diodes are reversed but maintaining the same polarity for the voltage
across the load resistor RL. The net effect is the same output as that appearing for full
wave rectifier with same d.c level.
Limitations of Center Tap Full wave Rectifier:
1.
It is difficult to locate center tap on the secondary winding.
2.
The DC output is small as each diode utilizes only one-half of the transformer
secondary winding.
3.
The diode must have high peak inverse voltage.
Full Wave Bridge Network:
Bridge network requires four diodes for its operation. The circuit diagram is shown in
figure 3.
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Figure 3
During the period 0 to t/2 diodes D2 and D3 are conducting while diodes D1 and D4
are in off state, so for the ideal diodes the load voltage Vo =Vi. For the negative
portion of the input voltage diodes D1 and D4 are conducting resulting in positive
pulse across load resistor RL.
Vdc=.636Vm
Advantages of Bridge Rectifier:
1.
The need for center tapped transformer is eliminated.
2.
The output is twice that of center-tap circuit for the same secondary voltage.
3.
The PIV is one half that of the center-tap circuit.
Disadvantages of Bridge Rectifier:
1.
It requires four diodes.
2.
As during each half cycle of ac input diodes that conduct are in series, therefore
the voltage drop in the internal resistance of the rectifying unit will be twice as
great as in the center circuit. This is objectionable when secondary voltage is
small.
Important parameters for rectifier circuits:
Peak inverse voltage :
The maximum reverse-bias potential that can be applied to a diode before entering the
Zener region is called peak inverse voltage or peak reverse voltage.
Half wave Rectifier PIV rating ≥ Vm
Center tap Full wave Rectifier PIV rating ≥ 2Vm
Full wave Bridge Rectifier PIV rating ≥ Vm
Rectification efficiency:
The ratio of DC output power to the AC power input in a rectifier is known as
rectification efficiency.
η = DC output power
AC input power
Efficiency of Half wave rectifier:
Pdc =I2dc× RL= {Im/ п} 2× RL
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Pac=I2rms (rf+ RL), Irms =Im/2
rf is diode resistance
η = Pdc / Pac =0.406/ (1+ rf / RL) …………..……. (1)
Efficiency of Full wave rectifier (Center tap and Bridge Rectifiers):
Idc=2Im/ п, Pdc =I2dc× RL= {2Im/ п} 2× RL
Irms =Im/√2, Pac=I2rms (rf+ RL)
η = Pdc / Pac = 0.812/ (1+ rf / RL) …………..……. (2)
Ripple factor:
The ratio of r.m.s. value of AC component to the DC component in the rectifier output
is known as ripple factor. The smaller the ripple factor, the lesser the effective AC
component and hence more effective is the rectifier.
Ripple factor = r.m.s. value of AC component
Value of DC component
Mathematical analysis
Ripple Factor= √ (Irms / Idc ) 2-1
………………………. .…….(3)
Half wave rectification:
Irms =Im/2
;
Idc=Im/ п
Putting values in eq.3 we get
Ripple Factor=1.21
Full wave rectification:
Irms =Im/√2
;
Idc=2Im/ п
Putting values in eq.3 we get
Ripple Factor=0.48
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Comparison of Rectifiers:
S. No.
Particulars
Half -wave
Center -tap
Bridge type
1.
No. of diodes
1
2
4
2.
Transformer
necessary
no
yes
no
3.
Max..efficiency
40.6%
81.2%
81.2%
4.
Ripple factor
1.21
0.48
0.48
5.
Output frequency
fin
2 fin
2 fin
6.
Peak inverse voltage
Vm
2Vm
Vm
Filter circuit:
The output of a rectifier has a pulsating character i.e. it contains AC and DC
components. However, in electronic circuits, we need a DC voltage that is constant
value .So a filter circuit is installed at the rectifier output .The filter circuit filters out
the AC components from the rectifier output and allows only the DC component to
reach the load .Thus a constant DC voltage appears across the load.
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Experiment 1
Objective:
To study Half wave Rectifier Circuit.
Equipment Needed:
1.
Analog board of AB09.
2.
AC power supplies of 0-9Vrms from external source or ST2612 Analog Lab.
3.
Oscilloscope.
4.
2 mm patch cords.
Circuit diagram:
Circuit used to study the Half wave Rectifier is shown in figure.4
Figure 4
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AB09
Procedure:
•
Connect 0-9Vrms from ST2612 Analog Lab or from Analog Digital Lab
Power Supply or from any external source (transformer o/p or function
generator) to sockets m and c of AB09 Board respectively using 2mm patch
cords.
1.
Connect 2mm patch cord between sockets e and j. This will connect load
resistance RL across the output of half wave rectifier.
2.
Connect Ch I of oscilloscope between sockets i and n and observe the half wave
rectified o/p waveform across the load resistor (keep AC/DC push button switch
of oscilloscope in AC position)
3.
Measure the output DC voltage by pressing the AC/DC push button switch of
the oscilloscope or by connecting a digital multimeter across sockets j and n i.e.
across load resistance and carry out following calculations.
4.
Now connect the 2mm patch cord between i and l socket. This will connect the
filter capacitor across the o/p of half wave rectifier.
5.
Observe the filtered output on oscilloscope.
Results:
1.
Output voltage Vo =…………………………………..
2.
Efficiency (using eq.1) = ………………………………
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AB09
Experiment 2
Objective:
To study Full wave Center- tapped Rectifier Circuit.
Equipment Needed:
1.
Analog board of AB09.
2.
AC power supplies of 9-0-9Vrms from external source or ST2612 Analog Lab.
3.
Oscilloscope.
4.
2 mm patch cords.
Circuit diagram:
Circuit used to study the Full wave Rectifier is shown figure 5
Figure 5
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AB09
Procedure:
•
Connect 9V-0-9Vrms from ST2612 Analog Lab or from Analog Digital Lab
Power Supply or from any external source (transformer o/p) to sockets c, m and
g of AB09 Board respectively using 2mm patch cords.
1.
Connect 2mm patch cord between sockets e and j. This will connect load
resistance RL across the output of Center tap Full wave rectifier.
2.
Connect Ch I of oscilloscope between sockets i and n and observe the Center tap
Full wave rectified o/p waveform across the load resistor (keep AC/DC push
button switch of oscilloscope in AC position)
3.
Measure the output DC voltage by pressing the AC/DC push button switch of
the oscilloscope or by connecting a digital multimeter across sockets j and n i.e.
across load resistance and carry out following calculations.
4.
Now connect the 2mm patch cord between i and l socket. This will connect the
filter capacitor across the o/p of center tap full wave rectifier.
5.
Observe the filtered output on oscilloscope.
Results:
1.
Output voltage Vo =…………………………………..
2.
Efficiency (using eq.2) = ………………………………
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Experiment 3
Objective:
To study Full wave Bridge Rectifier Circuit
Equipment Needed:
1.
Analog board of AB09.
2.
AC power supplies of 0-9Vrms from external source or ST2612 Analog Lab.
3.
Oscilloscope.
4.
2 mm. patch cords.
Circuit diagram:
Circuit used to study the Full wave bridge Rectifier is shown in figure 6
Figure 6
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AB09
Procedure:
•
Connect 0-9Vrms from ST2612 Analog Lab or from Analog Digital Lab
Power Supply or from any external source (transformer o/p) to sockets g and c
of AB09 Board respectively using 2mm patch cords.
1.
Connect sockets b with d and h with f using 2mm patch cords to complete the
bridge rectifier circuit and also connect a patch cord between socket a and m/n.
2.
Connect 2mm patch cord between sockets e and j. This will connect load
resistance RL across the output of Bridge rectifier (keep AC/DC push button
switch of oscilloscope in AC position)
3.
Output DC voltage can be measured by pressing the AC/DC push button switch
of the oscilloscope or connecting a digital multimeter across sockets j and n i.e.
across the load resistor and carry out following calculations.
4.
Now connect the 2mm patch cord between i and l socket. This will connect the
filter capacitor across the o/p of full wave bridge rectifier.
5.
Observe the filtered output on oscilloscope.
Results:
1.
Output voltage Vo =………………………………….
2.
Efficiency (using eq.2) = ………………………………
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AB09
Data Sheet
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AB09
Warranty
1.
We guarantee this product against all manufacturing defects for 24 months from
the date of sale by us or through our dealers. Consumables like dry cell etc. are
not covered under warranty.
2.
The guarantee will become void, if
a)
The product is not operated as per the instruction given in the Learning
Material
b)
The agreed payment terms and other conditions of sale are not followed.
c)
The customer resells the instrument to another party.
d)
Any attempt is made to service and modify the instrument.
3.
The non-working of the product is to be communicated to us immediately giving
full details of the complaints and defects noticed specifically mentioning the
type, serial number of the product and date of purchase etc.
4.
The repair work will be carried out, provided the product is dispatched securely
packed and insured. The transportation charges shall be borne by the customer.
List of Accessories
1.
2.
3.
4.
2mm Patch Cord (Red) 16” ................................................................ 2 Nos.
2mm Patch Cord (Black) 16”................................................................ 1 No.
2mm Patch Cord (Blue) 16” ............................................................... 5 Nos.
Learning Material (CD) ........................................................................ 1 No.
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