Table Of Content41 Projects
using
741 OP Amp
Publishers
‘Business Promotion Bureau
376, Lajpat Rai Market, Dethi-1101N6
41 Projects
using
741 OP Amp
MC. Sharma, M.Sc.
Publishers
Business Promotion Bureau
376, Lajpat Rai Market, Delhi-110006
©BUSINESS PROMOTION BUREAU
‘0, at Ram Rea, Days Gon) EW DELETE,
0, Stet, oa Hon, MADBAS 02
{6 ie Law, Bo Sa, YDERABAD SDL
yt same outbor:
Practical Transtar Novelies
‘Simple Audio Frojees
Practical SCR/Trize Projects
[Easy to Build Electronic Alarms
Using Field Effect Transistors
1555 Timer-Use and Apptcations
‘Build Your Owa Test festeuents
‘Understanding and Using Mullimeters
Digital Integrated Cieuis-Lenraing by Experiavents
Using Semi-conductor Diodes
Power Supplies for All Gmasions
Care and Repair of Electronic Pash Guns
CMOS Integrated Ciewits-Learning by Experiments
‘Using Funetioin Generaiors and Phase Lock loops
FIRST EDITION 182,
‘bie Gla orbs mtn ren
‘316, Ljpat Ral Mate, BEL He.
Photogpethy NX. ENTERPRISES Dargush Now Dei 2002
Pred at Stack Pinte, 16% 52-Geh Rd, Bw D885
PREFACE
‘The Gpetationsl Amplifier 1C741 i perhaps one ofthe mest
‘inexpensive IC availabe nthe market. Yer is comparable to the
best of such ICs in respect of versailty and eaperb peformunce It
is, therefore, natural that there is hal any electron magazine in
{he world wien does not contain a project using this 1C
‘This book whichis noW in your anes contains 4 projcesemp-
loying his IC. You wil find the eletrisal detail of his ICin the book
itself which make them so verse
These projects will provide the hobbyist, the expecimenter and
{even the professional, practical experience in making thes rot
Tm this connection, we Would Hke to emphasise two aspect: Rt,
soodsolderingan the aseofTCSockes. Iti not proposed to gainto
‘he details food soldering, but, lease aearinmind badly-soldered
Jos il invariably dsappeint you in the performance of the peo-
Jeet, no matter now well the ei is designed or how gud ure the
{ndltidual components.
Secondly itisalvays 2 good practice tuse an IC socket, wire it
‘up and then insert the IC inthe socket inthe CORRECT wa.
AC thls stage, itil be appropriate to indicate tat tis IC741
capable of driving a loudspeaker ugectly. fs output is usualy
‘enmmected to an ouput amplifier rage, Al times, tome, this IC
gy be designed 19 aeuate a par of earphones.
‘he wuthor Mr. M.C; Sharmais not new 1 our reers, Sugaee-
‘ious for improvement wil be gratefully recetved by him as wel es
‘osislves
Publishers
Sa ty
coNsENTS
1 INTRODUCTION
2, PRACTICAL PROJECTS.
3. POWFR SUPPLIES
Inventing DO Amplifier
Non-laverting DC Amplifier
Inverting AC Amplifier
Nop-Tavertng AC Amtifer
DC Votage Follower
| AC Voltage Follower
‘iat Peknp Preamplifier
Magnetic Pickin Preamplifier
“Magnetic Mike Preamplifier
Guitar Presence
“Telephone Pekup Preamplifier
Mier Amplifier
Tone Canto
Signal Tracer
3W Ampliier
Intercom
1W Amplifier
19 Motat Control
‘AC Motor Control
Schmit Tigeer
Square Wave Generator
Puke Generator
Maltitone Bell
EketronicSiren
‘Monostable Muivibmator
Bistable Mulibator
“Trgger Pulse Generator
lather
Timer
Light Opernted Relay
PoworFallure Indicator
“Tous Contoller
EM Tuning Indiestor
Positive Reference Voltage
Nepitine Reference Voltage
Repiated Power Supply
DC Voltmeter
AC Milivottmeter
Micoampers Motor
Engine RPM Counter
‘Analog to Digital Converter
INTRODUCTION
‘An operational amplifier, offen refered to a6 an Op Amp, 3
veryhigh sain high performance ampliietdesignedto amplify cand
Ge signal yollages, Moder integrated cat tchnolony and lag
‘Scale production techniques have brought doven the prices of such
Smplifirs within each ofall amateurs, experimenters hobby.
‘The Op Amp is pow wed as a basie gai clement, Ike an cept
transistor, in electronical
“ig, Shmtolforan Opeitom! Ample
‘A symbol used to represent an operational amplifier ia schemat-
ics is shown in Fiz 1. The operational amplifiers two fnpatsand
fonly one output One iapit i called the inverting input and is
denoted by 9 tinassign, A signal applied to thisinputappesrsas an
mplifed bat phase verted signal at the output. The s-condinpatis
Called 9 noninverting inp and denoted by a plus sin. A senal
Sprlied to thi input appears at the culgut 3s an amplified signal
‘which has the same phase a at ofthe fnpa ral
‘The availabilty of eo input terminals simplifies feedback
Litclly an aes the operational empliier a higly versa de
‘ee. Ts feedtaes js applied fom the output to the investing input
he result isa negative feedback whch gives sable ap
lier with precisely controlled On the other
hand, if the fede iil 0 theres
is poctive edb ors
dial effets ace obs ofl yp of ecdacks
Fi 2.Pia Conipiraton for 7410p Arp
(Of the different types of operational amplifiers produced, type
“at has achieved «very wile populriy. Iisavaiabiein 1-pan dual+
in-ine, pn duabincne orb TO-sile packages, Pin conbigsrations
forall these packages are shown in Fle.
Fig 3. Fia Conbguation, for ype 77 Dust Op Arp
3
Integrated Great type 747 seconunodates two tp 744 oper
‘tional amplifiers ina singlo package, Pin configuretion for diferent
packages sec showa a Fig.
“The operational amplifier ncads «dual syaumetecal power 2rphy
swith is conte tap founded as ahowa la Fig. 1. This enables the
Dperationsl amplifer to orplity designate of bt polarity, posive
Srinezatve, with respect to pround, Tho circuits designe that
bth inputs sre connected 10 ground, the de oatpt voltage i 20,
However, booause of small internal unbalance, small de voltage
‘nay appcae a tke eutpat. t= toosmal tobeobjenionablaia normal
Spplictines, For crite applications, the ostputvelago ean beset
[poly to zero by connecting a 10k potentometee botveen tenn
‘nals marked “ofist mill” as shewa in gure and S.
1Wispoasbleto operet the 74 om sing ealeapply ako Tiki,
usually done by rating the standing de input voltage to the #08:
[nvertineinpat trmnioal co approsinatelybeitheropply elaasbya
‘elluge dividsenatvon, an done in figures 1 12 te The output
{olloge in such eaten stands athe the mopply-wllape. But this
hot attr Docauee the de can be ely blocked by a capadior
“owing only the ae signa tobe pened on wo tho sox stag
‘Operational amplifier pe 71 has many feautes that bave male
‘so popular, Tha a bul cixeuitey that provides ful prvesion
‘iainst output overloads or even shorts to ground for any length ct
time, The 741 does not need ny external enmponent Zor phase
‘compensation or adiosing its freapieney responte. This simplifies
rit design and minimises the ruber af components used Hs
frequenay response ha smooth olloff atthe highend which keeps
the cireuic folly stable jn all feedback nafiguetions. Important
technial parameters of ype Te are gion helo:
Parameter Min, Typ. Max. Unies
Supply Vattage +s 4
SopplyCarrent 1728 mA
Tepe Bias Curent 2 0 A
Trt Resistance 03 20 Ma
Tepat feet Voltage 20 60 om
Offs Voliage Adjustment
Range +5 mv
i .
‘i Parameter Min, Typ. Max. Unter
Voltage Gain 29,000 200,000
i Output Resistance 1% a
i ‘Output Short Chews
Current it aA
Gain Bandwih Product 1 Mit:
Slew Rate 0s View
Power Consumption 0 8 AW
‘The net chapter shows fore-one pratcal projsts using 744.
‘Two of mare ofthese can be combined to meet individual requie=
W ments, Chapter 3 gives practical power supply arrangements f0 op-
erste 741 fom aiterenteypes of primury power sources avaiable,
|The experizater eau ose the comet one foc his projet.
Ff
t
