Introduction to Linear Integrated Circuits

This Topic covers the Introduction to Linear Integrated Circuits and characterstics and OPamp

1. 1
20EC402
LINEAR INTEGRATED CIRCUITS
by
Mr.V.Bharathi M.E.,M.B.A.,(Ph.D)

2. UNIT-I
UNITIBASICSOFOPERATIONALAMPLIFIERS
BasicinformationaboutOp-amps-Symbol,PowerSupply
Connection,IdealOperationalAmplifier,InvertingAmplifier,
Non-InvertingAmplifier,VoltageFollower,DifferentialAmplifier,
Op-amp-BlockDiagram,DCcharacteristics,ACcharacteristics
-Frequencyresponse,FrequencyCompensation,Slewrate,open
andclosedloopconfigurations.
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3. INTEGRATED CIRCUITS
Anintegratedcircuit(IC)isaminiature,lowcost
electroniccircuitconsistingofactiveandpassive
componentsfabricatedtogetheronasinglecrystal
ofsilicon.
Theactivecomponentsaretransistorsanddiodes
Passivecomponentsareresistorsandcapacitors.
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4. ADVANTAGES OF IC OVER DISCRETE
COMPONENTS
Small size (around 20,000 components / square inch)
Improved performance (more complex circuits may be used)
Low cost
High reliability and ruggedness
Low power consumption
Less vulnerability to parameter variations
Easy troubleshooting (for replacement)
Simpler design of systems
Standard packaging
Increased operating speed (due to the absence of parasitic capacitance
effect)
Less weight and portable
Battery operated systems due to low power supply requirement
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5. DISADVANTAGES
AsICissmallinsize,itisunabletodissipatelargeamount
ofpower.Increaseincurrentmayproduceenoughheat
whichmaydestroythedevice.
Atpresentcoils,inductorsandtransformerscannotbe
producedinICform
OncetheICisdamageditcannotbeusedagain
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6. CLASSIFICATION OF ICs
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9. Current Mirror and Current Sources
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10. Current Mirror and Current Sources
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11. A current mirror is a circuit whose output current is a
replica of the current entering into the its input terminal
An ideal constant current source is an electric circuit that
supplies a constant current to the load that is independent of
voltage across the load.
In other words the current is maintained constant
irrespective of load conditions
The constant current source are widely used in analog
integrated circuits as biasing elements and load devices for
amplifier stages
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12. Operational Amplifier
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13. Why Operational Amplifier?
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Opamp is another kind of Differential Amplifier

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26. Ideal Operational Amplifier
Operationalamplifiersarelineardevicesthathaveall
thepropertiesrequiredfornearlyidealDC
amplificationandarethereforeusedextensivelyin
signalconditioning,filteringortoperform
mathematicaloperationssuchasadd,subtract,
integrationanddifferentiation
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27. AnOperationalAmplifierisbasicallyathree-terminal
devicewhichconsistsoftwohighimpedanceinputs.
OneoftheinputsiscalledtheInvertingInput,marked
withanegativeor“minus”sign,(–).Theotherinput
iscalledtheNon-invertingInput,markedwitha
positiveor“plus”sign(+).
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28. Athirdterminalrepresentstheoperationalamplifiersoutput
portwhichcanbothsinkandsourceeitheravoltageora
current.Inalinearoperationalamplifier,theoutputsignalis
theamplificationfactor,knownastheamplifiersgain(A)
multipliedbythevalueoftheinputsignalanddependingon
thenatureoftheseinputandoutputsignals,therecanbefour
differentclassificationsofoperationalamplifiergain
Voltage–Voltage “in” and Voltage “out” Vo/Vs
Current–Current “in” and Current “out” Io/Is
Transconductance–Voltage “in” and Current “out” Io/Vs
Transresistance–Current “in” and Voltage “out” Vo/Is
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29. Op-amp Parameter and Idealized Characteristic
Thecharacteristicsofanidealopampare:
1.InfiniteinputresistanceRi=∞
2.ZerooutputresistanceRo=0
3.InfiniteVoltagegainG=∞
4.InfiniteBandwidthBW=∞
5.InfiniteCommonmoderejectionratioCMRR=∞
6.InfiniteSlewrate SR=∞
7.ZeroOffset V1=V2;VO=0
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30. Equivalent Circuit of an Ideal
Operational Amplifier
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31. IC LM741
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34. Equivalent Circuit of an OPAMP
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35. An Inverting Op-Amplifier
InanIC741opamp,pin2andpin6aretheinputand
outputpins.Whenthevoltageisgiventothepin-2
thenwecangettheoutputfromthepin-6.Ifthe
polarityofthei/ppin-2is+Ve,thenthepolaritywhich
comesfromtheo/ppin6is-Ve.Sotheo/pisalways
oppositetothei/p
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37. Non Inverting Op-Amplifier
InanIC741opamppin3andpin6areinputandoutput
pins.Whenthevoltageisgiventothepin3thenwecanget
theoutputfromthepin-6.Ifthepolarityis+Veattheinput
pin-3,thenthepolaritywhichcomesfromtheo/ppin-6is
also+Ve.Sotheo/pisnotopposite
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38. IC 741 Op-Amp Characteristics
ThecharacteristicsoftheIC741operationalamplifier
includethefollowing
TheInputimpedanceoftheIC741opampisabove
100kilo-ohms.
Theo/pofthe741ICopampisbelow100ohms.
ThefrequencyrangeofamplifiersignalsforIC741op
ampisfrom0Hz-1MHz.
OffsetcurrentandoffsetvoltageoftheIC741opamp
islow
ThevoltagegainoftheIC741opampisabout
2,00,000.
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39. IC 741 Op-Amp Applications
TherearemanyelectroniccircuitsarebuiltwithIC741op
ampnamelyVoltagefollower,analogtodigitalconverter,
sampleandholdcircuit,voltagetocurrentandcurrentto
voltageconverting,summingamplifier,etc.The
applicationsoftheIC741operationalamplifierincludethe
following.
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40. IC 741 Op-Amp Applications
Variable audio frequency
oscillator using IC 741 Op
Amp
IC 741 Op Amp based
Adjustable Ripple RPS
Audio mixture for Four
channels using IC 741 Op
Amp
IC 741 Op Amp and LDR
based automatic light
operated switch
DC volt polarity meter
using IC 741 Op Amp
e-room thermometer using
IC 741 Op Amp
Listening of Bug using IC
741 Op Amp
Microphone Amplifier
using IC 741 Op Amp
IC 741 Op Amp Tester
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41. Operational Amplifier Characteristics
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57. Open Loop Opamp Configuration
The term open loop indicates that no feedback in any form is
fed to the input from the output
3 open loop configurations of opamp are
(i) Differential Amplifier
(ii)Inverting Amplifier
(iii)Non inverting Amplifier
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58. Open loop Differential Amplifier
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59. Open loop Differential Amplifier
In this configuration the inputs are applied to both the
inverting and Non inverting input terminals of the opamp
Input voltages are represented by Vi1and Vi2 .The source
resistance Ri1and Ri2
The output voltage is given by
V0=A(Vi1–Vi2)
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60. Inverting Amplifier
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61. Inverting Amplifier
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62. Non Inverting Amplifier
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63. Non Inverting Amplifier
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64. Closed Loop Configurations
The opamp can be effectively utilized in linear applications by
providing a feedback from the output to the input, either
directly or through another network.
1. Voltage Series
2. Voltage Shunt
3. Current Series
4. Current Shunt
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65. . Voltage Series
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66. Voltage Shunt
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67. Current Series
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68. . Current Shunt
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69. JFET OPERATIONAL AMPLIFIERS
TLO82
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72. Features
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