ed lab manual manual

8/10/2019 Ed Lab Manual Manual

1/93

BE 2/4-I sem ED Lab, ECE Dept, MVSREC

M.V.S.R Engineering College

Nadergul, Hyderabad

Department of

Electronics & Communication Engineering

Manual and bser!ation "oo#

Electronic De!ices $ab%Code EC '()*

1


2/93


".E %ECE* ++ ear, + Semester

2


3/93


3


4/93


MVSR Engineering CollegeNadergul, Hyderabad

Department oEle!troni!s " Comm#ni!ation Engineering

Ele!troni! De$i!es Lab%Code EC '()*

Name of t-e student

Class

Roll No

Semester

/cad ear

4


5/93


%


6/93


$+S0 1 E23ER+MEN0S

1& V-I !'ara!teristi!s o Sili!on an( )ermani#m (io(es an( meas#rement o stati! an( (*nami!

resistan!es

2& +ener (io(e !'ara!teristi!s an( its appli!ations as $oltage reg#lator

3& Design, realiation an( perorman!e e$al#ation o 'al a$e an( #ll a$e re!tiiers it'o#t ilters

4& Design, realiation an( perorman!e e$al#ation o 'al a$e an( #ll a$e re!tiiers it' C, L,

LC, . ilters

%& 0lotting t'e !'ara!teristi!s o B in Common Base !onig#ration an( meas#rement o '-

parameters

& 0lotting t'e !'ara!teristi!s o B in Common Base !onig#ration an( meas#rement o '-parameters

& 0lotting t'e !'ara!teristi!s o E in Common So#r!e !onig#ration an( meas#rement o

rans!on(#!tan!e an( Drain resistan!e

5& B Biasing Cir!#its

6& E Biasing Cir!#its

17& Common Emitter B 8mpliier an( meas#rement o )ain, ban(i(t', inp#t an( o#tp#t

impe(an!es

11& Common So#r!e E 8mpliier meas#rement o )ain, ban(i(t', inp#t an( o#tp#t impe(an!es

12& Emitter olloer/So#r!e olloer !ir!#ts an( meas#rements o )ain, ban(i(t', inp#t an( o#tp#t

impe(an!es

13& C'ara!teristi!s o Spe!ial (e$i!es 9 : an( SCR

14& C'ara!teristi!s o #nnel (io(e an( p'oto (io(e

/ppendi4

Meas#rement o '-parameters

C'ara!teristi!s o p'oto transistor


7/93



8/93


Department of

Electronics & Communication Engineering

Ele!troni! De$i!es Lab

;ame o t'e st#(ent or orar( Biase( Con(ition


14/93


14


15/93


@b> or Re$erse Biase( Con(ition< -

Vs@V> V(@V> I(@8>

1%


16/93


>. "SERV/0+NS or Si& Dio(e

@a> or orar( Biase( Con(ition V( @V> I(@m8>

1


17/93


@b> or Re$erse Biase( Con(ition< -

Vs@V> V(@V> I(@n8>

?. E23EC0ED 6R/3H

I @m8>

)e Si

V- F VI @8>

1


18/93


@. RES7$05

);. V+V/ A7ES0+NS

1& G'at (o *o# #n(erstan( b* a ?#n!tion (io(eP

2& Is t'e 0-; ?#n!tion (io(e a passi$e element or an a!ti$e elementP

3& G'at is t'e importan!e o t'e t*pe n#mber gi$en to t'e $ario#s (io(esP

4& G'at is meant b* potential barrier a!ross a 0-; ?#n!tionP

%& G'at is t'e signii!an!e o a (io(e as a (e$i!eP& G'at is !#t in $oltageP G'at is t'e $al#e o !#tin $oltage or )e

an( Si (io(es& G'at is t'e reason or t'e (ieren!e in !#tinPVoltage o )e an( Si&

& Eplain p'*si!all* 'o a 0-; ?#n!tion #n!tions as a re!tiier&

5& G'at is t'e epression or t'e total !#rrent in a 0-; ?#n!tionP No(oes it $ar* it' t'e applie( $oltageP

6& G'at (o *o# #n(erstan( b* a re$erse sat#ration !#rrentP G'at are t'e t*pi!al $al#esP

17& G'* is t'e magnit#(e o t'e !#rrent in t'e orar( biase( (io(e greater t'an t'at in t'e re$erse biase( (io(eP

11& No (oes t'e re$erse sat#ration !#rrent $ar* it' temperat#re or )e an( Si (io(esP Is it o signii!an!e 'ile t'e !ir!#it

(esigner !'ooses a parti!#lar (e$i!e in (esignP

12& G'at (o *o# #n(erstan( b* (*nami! an( stati! resistan!eP No

are t'ese $al#es obtaine( grap'i!all*P13& Deine t'e terms orar( an( re$erse resistan!e o a 0-;

#n!tion (io(e&

14& Eplain t'e !apa!iti$e ee!ts in a ?#n!tion&

1%& G'at are t'e $ario#s appli!ations o a 0-; ?#n!tion (io(eP

15


19/93


E23ER+MEN0 N'

Bener diode c-aracteristics and its applications as !oltage regulator

). /+M a> o obtain t'e $olt-ampere !'ara!teristi!s o +ener (io(e b> o obtain t'e reg#lation !'ara!teristi!s namel* 1> S#ppl* $oltage reg#lation !'ara!teristi!san( 2> Loa( reg#lation !'ara!teristi!s&

'. /33/R/07S

S&;o& Item Range/Spe!ii!ation At*1 +ener (io(e ES+ %&2 12 DC 8mmeter 7-%7 m8 1

3 DC Voltmeter 7-27 V 24 Resistor 2&2 QNal Gatt 1% Reg#late( 0oer S#ppl* 7-37 V 1 De!a(e Resistan!e Bo 1- 17 M 1 0at!' !or(s / Conne!ting ires

(. 0HER

Be!a#se o t'e eisten!e o an ele!tri! iel( a!ross a re$erse biase( ?#n!tion, it is possible to r#pt#re!o$alent bon(s& 'is !an be (one b* eerting a strong or!e on t'e bo#n( ele!trons so t'at t'e* are Jtornaa*K rom t'e bon(s& 'is pro!ess lea(s to a((itional ele!tron-'ole pairs& G'en a((itional ele!tron-'ole

pairs are generate(, t'e re$erse !#rrent in!reases& 'is me!'anism is !alle( +ener BreaQ(on, an( t'e$oltage at t'is point is !alle( ener $oltage, 'i!' remains irrespe!ti$e o t'e $ariations re$erses !#rrent,s#ppl* $oltage an( loa( resistan!e&

8$alan!'e BreaQ(on or 8$alan!'e M#ltipli!ation is a pro!ess 'erein, a !arrier a!#ires eno#g'energ* rom t'e applie( potential, to !olli(e it' a !r*stal ion an( (isr#pt a !o$alent bon(&G'en a bon( is (isr#pte( in t'is as'ion, a ne ele!tron-'ole pair is generate(& ;o, t'ese !arriers !analso gain energ* rom t'e applie( potential an( go on to (isr#pt ot'er !o$alent bon(s& 'is pro!essbe!omes !#m#lati$e lea(ing to large re$erse !#rrents&

'e strong iel( re#ire( or +ener BreaQ(on is rea!'e( in t'e range o 47V in 'ig'l* (ope(

(io(es& 'e 'ig' (oping !on!entration is re#ire( to 'a$e a s#i!ientl* t'in (epletion region& I t'e (epletion region is t'in, t'en a strong iel( is pro(#!e( t'at !an r#pt#re !o$alent bon(s& )enerall*t'e (oping !on!entration is aro#n( one imp#rit* atom per 17% sili!on atoms& 'e ele!tri! iel( at t'e?#n!tion is o t'e or(er o 17V/!m&In t'e re$erse !'ara!teristi! o a +ener (io(e, t'e Qnee $oltage is !alle( t'e breaQ(on Voltage V&

)enerall*, in lig'tl* (ope( (io(es, t'e (epletion region is relati$el* t'i!Q 8$alan!'e BreaQ(onis pre(ominant an( o!!#rs at 'ig'er $oltages& @8bo$e 5V>&

16


20/93


a* 0o obtain t-e !olt5ampere c-aracteristics of Bener diode

8. C+RC7+0 D+/6R/MS

or Re$erse Bias an( t'e !#rrent @as in(i!ate( b* t'eammeter>&

3> ab#late all rea(ings an( plot i $ers#s V&

or orar( Bias

1> Conne!t t'e !ir!#it as per t'e !ir!#it (iagram& Ens#re poer-s#ppl* $oltage Qnobs are in t'eminim#m position an( sit!' it on&

2> Var* t'e s#ppl* $oltage in small !on$enient steps& ;ote (on t'e !orrespon(ing $ales o orar($oltage @as in(i!ate( b* t'e $oltmeter> an( t'e !#rrent @as in(i!ate( b* t'e ammeter>&

27


21/93


3> ab#late all rea(ings& 0lot i $ers#s V&

. E23EC0ED 6R/3H

>. 0/"7$/R C$7MNS

orar( C'ara!teristi!s I+@m8>


22/93


Re$erse C'ara!teristi!s I+@m8>

22


23/93


b* Bener diode regulator c-aracteristicsVoltage reg#lator s'o#l( pro$i(e !onstant $oltage at an* (esire( $al#e irrespe!ti$e o $ariations in t'es#ppl* $oltage an( $ariations in t'e loa(& rom t'e re$erse !'ara!teristi!s o t'e +ener (io(e, at +enerBreaQ(on, $oltage a!ross (io(e remains !onstant irrespe!ti$e o t'e $ariations in re$erses !#rrent an(s#ppl* $oltage& Sin!e t'e !'ara!teristi!s o +ener (io(e satisies t'e orQing o a reg#lator, a $oltage

reg#lator #sing +ener (io(e is (esigne(& Reg#lation !'ara!teristi!s are (i$i(e( into line or $oltagereg#lation an( loa( reg#lation&

C+RC7+0 D+/6R/M 1 / BENER D+DE RE67$/0R

3RCED7RE

S#ppl* $oltage reg#lation @Line reg#lation> !'ara!teristi!s& Repeat t'e abo$e steps or $ario#s $al#es o Vin&

>& 0lot iL$ers#s V7&

23

F

-

17 -1M


24/93


E23EC0ED 6R/3HS

0/"7$/R C$7MNS

Voltage Reg#lation C'ara!teristi!s

IL 7&% m8 IL 1 m8Vin @Volts> Vo@Volts> Vin@Volts> Vo@Volts>

24

Voltage/Line Reg#lation Loa( Reg#lation


25/93


Loa( Reg#lation C'ara!teristi!s

Vin 12 Volts Vin 15 Volts

IL@m8> Vo@Volts> IL@m8> Vo@Volts>

2%


26/93


RES7$0

V+V/ VCE

1> G'at are t'e t*pi!al appli!ations o a +ener (io(eP

2> G'* a +ener (io(e is generall* not !onne!te( in orar( biasP

3> G'at is meant b* reg#lationP G'* is it re#ire(P

4> Deine t'e $ario#s t*pes o breaQ(on possible in (io(es&

%> )i$e t'e t*pi!al appli!ation o an a$alan!'e breaQ(on (io(e&

> G'at are t'e t*pi!al appli!ations o a +ener (io(eP

> ;ame t'e $ario#s t*pes o (io(es a$ailable

5> G'at is meant b* breaQ(on o (io(esP

6> No (o e test a (io(e #sing a m#ltimeterP

2


27/93


2


28/93


E23ER+MEN0 N(

REC0+1+ERS +0H70 1+$0ERS

/+Mo obtain ripple a!tor an( reg#lation o a 'al a$e an( #ll a$e re!tiier it'o#t ilters&

/33/R/07S< -S&;o& ;ame o t'e (e$i!e Range/;o A#antit*

1& Dio(es 1; 477 2 ;o& 2& Milli ammeter 7 - 2%m 8mp& 1 ;o&3& CR 27 M' 1 ;o&4& Center tape( ransormer -7- V 1 ;o&%& 0at!' !or(s

& Voltmeter 7-27 V 1 ;o&& De!a(e Resistan!e Bo 1T 9 17 M T 1 ;o&

0HER

Re!tiiers perorm t'e tasQ o !on$erting 8&C& to D&C& Commonl* #se( re!tiiers are Nal-Ga$eRe!tiier an( #ll-a$e Re!tiier&

Half a!e rectifier

'e basi! re!ti*ing element is a (io(e& 'is (e$i!e 'as essentiall* an ininite resistan!e@'en it is re$erse

biase(> to !#rrent lo in one (ire!tion an( a $er* small resistan!e @'en it is orar( biase(> or t'e!#rrent lo in t'e opposite (ire!tion&G'en t'e (io(e is orar( biase(, !#rrent los t'ro#g' t'e loa( resistan!e, lea(ing to t'e (e$elopmento a #ni (ire!tional o#tp#t a!ross it& G'en it is re$erse biase(, !#rrent is approimatel* ero, t'ereore$oltage (e$elope( a!ross t'e loa( is ero&

1ull5a!e Rectifier8s s'on in t'e ig#re in a #ll-a$e re!tiier t'e transormer se!on(ar* 'as a !enter-tap an( ea!' 'algi$e a peaQ $oltage o Vm& In ea!' 'al t'ere is one (io(e D1an( D2& 'e loa( resistan!e RLis !ommon tobot' 'al$es& Nen!e a #ll-a$e !ir!#it !omprises o to 'al-a$e !ir!#its& n t'e positi$e 'al !*!le'en t'e point 8 is F$e &r&t B, t'e (io(e D1!on(#!ts an( !#rrent i1 los t'ro#g' RL& D#ring t'e

negati$e 'al !*!le t'e point C is F$e &r&t to B an( 'en!e t'e (io(e D 2 !on(#!ts an( !#rrent i2 lost'ro#g' RL&

C+RC7+0 D+/6R/M

25


29/93


ig Nal a$ere!tiier

ig< #ll Ga$e Re!tiier

3RCED7RE for 17$$ /VE and H/$1 /VE REC0+1+ER

). Conne!t t'e !ir!#it as per t'e !ir!#it (iagram&'. C'oose an appropriate $al#e or t'e loa( resistor, sa*, 17 Q T&

(. bser$e t'e inp#t an( o#tp#t a$eorms on t'e CR an( $eri* 'et'er t'e* are as !an be epe!te(&8. Meas#re t'e peaQ $oltage Vmon t'e CR s!reen& :sing t'is $al#e o Vm, t'e $al#es o Irmsan( I(!!anbe !al!#late(&

=. Meas#re t'e DC !#rrent an( t'e DC $oltage in t'e ammeter an( t'e $oltmeter respe!ti$el*&. Meas#re t'e peaQ $oltage Vm@or t'e (! $oltage V(!, #sing t'e $oltmeter> at t'e no loa( !on(ition&>. MaQe !al!#lations a!!or(ing to orm#lae&

1RM7$/E

N8L G8VE RECIIER

I(! Im/2 , Irms Im/U

W@I(!/Irms>29 1X1/2

Reg#lation @Vno loa(9 V#ll loa(>/V#ll loa(

26


30/93


:LL G8VE RECIIER

I(! Im/1&414, Irms 2Im/URipple a!tor W@I(!/Irms>29 1X1/2

"SERV/0+NS

Re!tiier IDC@m8> VDC@V> I8C@m8> V8C@V> Ripplea!tor

Nala$e

re!tiier#lla$ere!tiier

RES7$0

V+V/ VCE

1> G'at is t'e a($antage o #sing a #ll a$e re!tiier o$er a 'al a$e re!tiierP

2> G'at is a bri(ge re!tiierP G'at is t'e a($antage o #sing it o$er a #ll a$e re!tiierP

3> G'at is t'e 0eaQ In$erse Voltage in t'e !ase o #ll a$e an( 'al a$e re!tiiersP

4> Deine reg#lation an( ripple a!tor& G'at are t'e i(eal $al#es or t'ese #antitiesP G'at are t'e

pra!ti!al $al#esP%> No (o e remo$e ripple rom a re!tiier o#tp#tP

> G'at is a ilterP G'at is its #seP

> G'at is a reg#latorP G'* is it re#ire(P

37


31/93

BE 2/4 9 I sem ED Lab, ECE Dept&, MVSREC

31


32/93


E23ER+MEN0 N8

REC0+1+ERS +0H 1+$0ERS

/+Mo obtain ripple a!tor o a #ll a$e re!tiier it' ilters&

/33/R/07S

S&;o& ;ame o t'e(e$i!e

Range/ ;o At*

1 Si (io(e I;477 22 D M M 23 8&C poer

s#ppl*237V,%7N 1

4 Conne!tingires

% Resistor 1 1 C R 1

0HER8 #ll a$e re!tiier !on$erts a ero a$erage $al#e signal into a signal 'i!' is #ni(ire!tional it' somea$erage $al#e& 'e to (io(es in t'e !ir!#it are !onne!te( in s#!' a a* t'at t'e !on(#!tion or one 'al!*!le @F$e> taQes pla!e t'ro#g' one (io(e @sa* D> an( t'e (io(e D2is not !on(#!ting& In t'e net 'al

32


33/93


!*!le (io(e D1is not !on(#!ting an( D2is !on(#!ting& 'e !#rrent loing t'ro#g' t'e loa( is ala*s int'e (ire!tion& 'e !#rrent loing t'ro#g' t'e loa( is t'e s#m o t'e loa( !#rrents&

REC0+1+ER +0H70 1+$0ER

Regulation

I(! 2Im/

Irms Im/ Y2

Im Vm/ @RF RL>

Ripple a!tor rms $al#e o alternating !omponents o a$e / a$erage $al#e o a$e

Ripple a!tor @> Y W@Irms/ I(!>291X

Irms/ I(! @Im/ 2> / @2Im/ > 1&11

Y@1&112 9 1> 7&452

Regulation

V(! @2Vm/ > 9 @I(!R>

Vno loa( 2Vm/ @be!a#se I(! 78>

V#ll loa( 2 Vm/ - I(!R

Reg#lation @Vnoloa(9 V#ll loa(> / V#ll loa(

17$$ /VE REC0+1+ER +0H +ND7C0R 1+$0ER

'e impe(an!e o in(#!tor in!reases it' re#en!* 'en!e better iltering a!tion o!!#rs or 'ig'er 9

'armoni! terms& 'e a$eorm in t'e o#tp#t is epe!te( to be prin!ipall* o se!on( 'armoni!&

Ripple 1actor

W2 / @3 Y2> XW1 / Y@1 F 4Z2L2/ RL2>X

I 4Z2L2/ RL2 1

33


34/93


RL/W3Y2& ZLX

Regulation

V(! ;o Loa( 2Vm/

V(! #ll Loa( 2Vm/ - I(!R - @3>

R 9 is t'e total resistan!e o t'e !ir!#it e!l#si$e o t'e loa(i&e& RRFRCFRS 'ere Ris t'e orar( resistan!e o (io(e, RCis t'e !'oQe resistan!e an( RSis t'eresistan!e o t'e se!on(ar* in(ing&

C/3/C+0R 1+$0ER

V(! no loa( Vm

V(! #ll loa( Vm9 @Vr/ 2> G'ere Vris t'e total !apa!itor (is!'arge $oltage or t'e ripple $oltatge&

Ripple 1actor

Vrms/ V(! 1 / @4 Y3 CRL>

@Vr/2>/@Vm 9Vr/2>

L 9 SECI; ILER

$5section filter

Ripple 1actor

r Vrms/ V(! 2 ! / 3 L

@Y2> / @12Z2LC>

5 SEC0+N 1+$0ER

Regulation

V(! no loa( Vm

34


35/93


V(! #ll loa( Vm9 Vr/ 2

Ripple 1actor

R& 1/@4Y2 Z3C2L >

C+RC7+0 D+/6R/MS

GIN I;D:CR ILER Cal!#late t'e reg#lation an( ripple a!tor #sing t'e appropriate relations&> Veri* t'e res#lts #sing t'eoreti!al !al!#lations&

3/R0 F "@:sing a !apa!itor ilter>

1> Conne!t a !apa!itor ilter to t'e #ll a$e re!tiier !ir!#it&2> bser$e t'e inp#t an( t'e o#tp#t a$eorms on t'e os!illos!ope&

3


37/93


3> Meas#re t'e DC !#rrent t'ro#g' t'e loa(&4> Meas#re t'e ripple $oltage an( t'e peaQ $oltage o t'e o#tp#t a$eorm rom t'e os!illos!ope&%> Cal!#late t'e ripple an( reg#lation #sing t'e appropriate relations> Veri* t'e res#lts #sing t'eoreti!al !al!#lations&

3/R0 F C@:sing L 9 Se!tion ilter>1> MaQe t'e !onne!tions as per t'e !ir!#it (iagram&2> Conne!t an L-Se!tion ilter as s'on&3> bser$e t'e inp#t an( t'e o#tp#t a$eorms on t'e s!illos!ope4> Meas#re t'e (! !#rrent loing t'e !ir!#it #sing t'e DC 8mmeter&%> Meas#re t'e peaQ $oltage an( t'e ripple $oltage o t'e o#tp#t a$eorm&> Meas#re t'e series resistan!e o t'e !'oQe, @R!> resistan!e o t'e

transormer in(ing @Rs> an( t'e (io(e orar( resistan!e @R>> Cal!#late reg#lation an( ripple a!tor #sing appropriate relations5> Veri* t'e res#lts #sing t'eoreti!al !al!#lations&

3/R0 F D @:sing a - Se!tion ilter>

1> MaQe t'e !onne!tions b* !onne!ting all t'e !apa!itors an(in(#!tors in t'e !ir!#it&

2> bser$e t'e o#tp#t a$e orm on t'e s!illos!ope&3> Meas#re t'e (! !#rrent @I(!> loing t'ro#g' t'e !ir!#it&4> Meas#re t'e peaQ $oltage an( t'e ripple $oltage on t'e os!illos!ope&%> E$al#ate t'e ripple a!tor an( reg#lation #sing t'e appropriate relations&> E$al#ate t'e res#lts t'eoreti!all* an( $eri*&

E$al#ate t'e ripple a!tor an( reg#lation #sing t'e relations gi$en belo&

Ripple a!tor @ r > 2 [C/ RL [C1/ [L1 2 1 / 2GC 9 1 / RL9 1 / 2GC1 2GL1

Reg#lation< V(! no loa(9 V(! #ll loa(/ V(! #ll loa( Vno loa( Vm V(! #ll loa( Vm9 I(! 1 / 4! 9 I(!-R

G'ere I(! V(!/ RL, R Resistan!e o t'e transormerin(ing F !'oQe F (io(e

E23EC0ED /VE1RMS

3

8&C inp#t a$eorm to t'e#lla$e re!tiier

! %$olts*

t %se!*


38/93


35

! %$olts*

t %se!*

$ma $

min#tp#t a$eorm o t'e #lla$ere!tiier it' Capa!itor ilter

! %$olts*

t %se!*

#tp#t a$eorm o t'e #lla$eRe!tiier it'o#t ilter

! %$olts*

t %se!*

$ma $

min#tp#t a$eorm o t'e #lla$ere!tiier it' In(#!tor ilter


39/93


"SERV/0+NS

ilter se!tion IDC@m8> VDC@V> I8C@m8> V8C@V>

'eoriti!al

Ripplea!tor

0ra!ti!al

Ripplea!tor

In(#!tor ilter

Capa!itorilter

L-Se!tionilter

0i se!tionilter

RES7$0

36

! %$olts*

t %se!*

#tp#t a$eorm o t'e#lla$e re!tiier it' .-se!tion ilter

! %$olts*

t %se!*

$min

$ma #tp#t a$eorm o t'e #lla$e

re!tiier it' L-se!tion ilter


40/93


V+V/ 5 VCE

1& G'* is t'e ripple re#en!* (o#ble t'e $al#e o t'e s#ppl* re#en!* in t'e !ase o a #ll a$ere!tiier&

2& Eplain t'e importan!e o ripple an( reg#lation in t'e !ase o a re!tiier&

3& 8 !apa!itor ilter pro$i(es nearl* Vm$olts at lig't loa(, b#t t'e $oltage reg#lation is poor&

4& Eplain t'e reason or a poor reg#lation in t'e !ase o a GR it' !apa!itor ilter&

%& Eplain '* onl* t'e in(#!tor or t'e !apa!itor alone are not #se( as ilters to a GR !ir!#it& In ot'eror(s (is!#ss t'e (isa($antages o onl* C or onl* L ilter&

& G'i!' ilter !ir!#it (o *o# preer in !on$erting t'e re!tiie( o#tp#t $oltage to a p#re (! $oltage& )i$ereasons& Consi(er t'e !ases o a lig't loa( an( large loa(s&

47


41/93

BE 2/4 I- sem ED Lab, ECE Dept&, MVSREC

E23ER+MEN0 N =

CMMN "/SE 0R/NS+S0R CH/R/C0ER+S0+CS

/+M o obtain inp#t an( o#tp#t !'ara!teristi!s o a !ommon-base transistor&

/33/R/07S

Sl&;o&;ame o t'e (e$i!e

Range /;o At*&

1& 8mmeters 7 917 m8 72

2& Resistor 2&2 71

3& ransistor BC 17 71

4& M#lti meter/Voltmeter ----- 71

C+RC7+0 D+/6R/M

0HER

'e !ir!#it s'on in t'e ig#re abo$e, is reerre( to as Common Base or CB !onig#ration, sin!e t'e baseis !ommon to bot' inp#t an( o#tp#t !ir!#its& or an ;0; ransistor, t'e largest !#rrent !omponents are(#e to t'e ele!trons& 'e emitter-base ?#n!tion is ala*s orar( biase( @t'e $oltage being VEB>an( t'e!olle!tor-base ?#n!tion is re$erse biase( @t'e $oltage being VCB>& 'e $ario#s !#rrents are relate( b* t'e e#ation

IEIBFIC

rom t'e e#ation, e see t'at o#tp#t !#rrent ICis !ompletel* (etermine( b* inp#t !#rrent IEan( t'eo#tp#t $oltage VCBVC& 'e o#tp#t relation ma* be ritten in impli!it orm as

41


42/93


IC@VCB,IE>

Similarl*, in impli!it orm, t'e inp#t !'ara!teristi! is gi$en b*VEB@VCB,IE>

'e o#tp#t !'ara!teristi! is a plot o IC$ers#s VCBit' emitter !#rrent IEas a parameter&'e inp#t !'ara!teristi! is a plot o IE$ers#s VEBit' VCBas a parameter&

E4planation of c-aracteristics

In !ommon-base !onig#ration, t'e emitter-base ?#n!tion a!ts liQe a orar( biase( ?#n!tion& 'ereore,t'e inp#t !'ara!teristi!s are not'ing b#t t'e $olt-ampere !'ara!teristi!s o t'is ?#n!tion (io(e& 8s in asemi!on(#!tor (io(e, t'ese !'ara!teristi!s also 'a$e a !#tin $oltage& 8n in!rease in t'e magnit#(e o VCB!a#ses t'e magnit#(e o IEto in!rease it' VEB'el( !onstant& 'is in!rease is attrib#te( to a p'enomenon!alle( base-i(t'-mo(#lation or Earl* Ee!t& 'ereore, t'e !#r$es s'it letar(s it' in!reasing VCB&In, t'e o#tp#t !'ara!teristi!s, e !an i(enti* t'ree regions& 'e* are 8!ti$e Region, Sat#ration Region

an( C#to Region&In t'e a!ti$e region, t'e !olle!tor ?#n!tion is re$erse biase( an( t'e emitter ?#n!tion is orar( biase(& Int'e sat#ration region, bot' emitter an( !olle!tor ?#n!tions are orar( biase(& 8n( in t'e !#to region,bot' emitter an( !olle!tor ?#n!tions are re$erse biase(&'e !'ara!teristi!s are s'on in t'e epe!te( grap's&

3RCED7RE

+nput C-aracteristics< -1& MaQe t'e !onne!tions as per t'e !ir!#it (iagram&2& C'oose a $al#e or VCB, sa*, 7V&3& B* maintaining VCBat t'e !'osen $al#e, $ar* t'e s#ppl* $oltage VEEin small !on$enient

steps& Ea!' time, note t'e $al#e o VEBan( t'e !orrespon(ing $al#e o IE&4&ab#late all rea(ings&%& C'oose anot'er $al#e o VCBan( repeat t'e abo$e pro!e(#re&

& 0lot IE$ers#s VEB&

utput C-aracteristics< -1& Conne!t t'e !ir!#it as per t'e !ir!#it (iagram&2& C'oose a $al#e or IE, sa*, 1 m8& Var* t'e poer s#ppl* VEEtill t'e ammeter rea(s t'is $al#e o IE&3& ;o, $ar* t'e poer-s#ppl* VCC in small steps& Ea!' time, note (on t'e $al#e o VCB an( t'e

!orrespon(ing $al#e o IC&4& ab#late all obser$ations&%& C'oose anot'er $al#e or IEan( repeat t'e abo$e steps&& 0lot IC$ers#s VCB&

42


43/93


"SERV/0+NS IE@m8> VEB@V> IE@m8>

43


44/93


:0: CN8R8CERISICSIE

m8

IE 4m8

IE 2m8

VCB@Volts>

I;0:CN8R8CERISICS

VCB 4V

44

IE 2m8 IE 4m8

VCB@V> IC@m8> VCB@V> IC@m8>


45/93


IE@m8> VCB 2 VCBV

VEB@Volts>

RES7$0

V+V/ VCE

1> G'at (o *o# #n(erstan( b* t'e term Bipolar #n!tion ransistorP

2> G'at are t'e $ario#s t*pes o ransistors a$ailable& 8re t'ere an* preerre( t*pes i so '*P

3> G'at (o *o# #n(erstan( b* inp#t an( o#tp#t !'ara!teristi!sP

4> Disting#is' beteen a!ti$e, sat#ration, !#to regions an( internal operations o a BP

%> Dis!#ss t'e $ario#s (oping le$els in t'e emitter, base an( !olle!tor regionsP

> Eplain t'e p'*si!al str#!t#re o a BP

> Dis!#ss t'e !#rrent !omponents in a B in CB !onig#rationP

5> Eplain '* t'e base i(t' is Qept etremel* smallP

6> 8 0;0 ransistor operating in t'e a!ti$e region, etremel* small no& o 'oles in?e!te( into t'e base

re!ombine it' ele!trons in t'e narro base region b#t t'e 'ole (ensit* at ! be!omes ero& Eplain

'oP17> Eplain Earl* Ee!tP

11> G'* (oes t'e emitter !#rrent in!rease it' in!rease in re$erse bias at

t'e !olle!tor ?#n!tionP

12> G'at is meant b* !olle!tor re$erse sat#ration !#rrentP

4%


46/93


13> Grite t'e !olle!tor !#rrent epression or B in CB !onig#ration in

1& C#to region 2& 8!ti$e region 3&sat#rationP

14> Dis!#ss t'e s'apes o CB stati! inp#t an( o#t p#t !'ara!teristi!sP

1%> Eplain '* stati! o/p !'ara!teristi!s o a CB ransistor 'a$e slig't

#par( slopeP

1> G'at is bottoming ee!tP

1> G'at are t'e $al#es o VBE !#to VBE sat, VBE a!ti$e, VCB o,

VCB a!ti$e ,VCB satP

15> Eplain t'e perorman!e o t'e transistor as an ele!troni! sit!'P

16> Is t'e B ransistor a !#rrent !ontrolle( (e$i!e or a $oltage-

!ontrolle( (e$i!eP

27> 8 B in CB !onig#ration is a goo( -------------------------8mpliier be!a#se -----------------------

4


47/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC

4


48/93


45


49/93


E23ER+MEN0 N

CMMN EM+00ER CN1+67R/0+N

/+Mo obtain t'e inp#t " o#tp#t !'ara!teristi!s o B in !ommon emitter !onig#ration&

/33/R/07S

S&;o& ;ame Range/Spe!ii!ation At*1 ;0; B BC17 12 Resistor 1&5 QT 13 Resistor 5 QT 14 Voltmeter 7-17 V 1% Mi!roammeter 7-277 \8 1 Milliammeter 7-17 m8 1 D#al C'annel

Reg#late(0oer S#ppl*

7-37V 1

46


50/93


C+RC7+0 D+/6R/M

VCE

&

0HER

'ere are to sets o !'ara!teristi!s t'at !an be (ran or a B in !ommon emitter !onig#ration& 'e*are t'e inp#t an( t'e o#tp#t !'ara!teristi!s& 'e inp#t !'ara!teristi!s are obtaine( rom t'eolloing relation&

VBE@VCE,IB> G'ere VBEis t'e base to emitter $oltage, VCE is !olle!tor to emitter $oltage an( IBstan(s or abase!#rrent&'e o#tp#t !'ara!teristi!s are obtaine( rom t'e olloing relation 'ere IC is t'e !olle!tor !#rrent

+nput c-aracteristics !#t o region @iii> sat#ration region&

%7


51/93


/cti!e region In t'e a!ti$e region t'e emitter base ?#n!tion @E> is orar( biase( an( !olle!tor base?#n!tion@C> is re$erse biase(& In t'e a!ti$e region !olle!tor !#rrent respon(s more rea(il* to an* inp#tsignal& 'e operation o t'e !ommon emitter stage is #se( as an ampli*ing stage onl*& D#e to JEarl*Ee!tK, t'e !#rrent gain in!reases it' in!rease in VCE& 'e large slope o t'e !'ara!teristi! !#r$e o t'eCE transistor signiies t'at t'e in!remental o#tp#t impe(an!e o t'e B in CE is loer t'at t'at in CB

!onig#rationCutoff region 'e transistor is sai( to be in !#t o 'en emitter !#rrent is ero& or a!'ie$ing t'is!on(ition, it is not eno#g' to 'a$e t'e base !#rrent IB 7, be!a#se e$en it' IB7, t'e !olle!tor !#rrentIC@1F]>IC7& So, in or(er to a!'ie$e !#to !on(ition, it is ne!essar* to slig'tl* re$erse-bias t'e emitterbase ?#n!tion, 'i!' !an be a!'ie$e( b* appl*ing 7&1 $olt or )ermani#m an( 7V or sili!on& 'is illens#re t'e re#ire( !on(itions or !#to i&e&IE 7, IC IC7, IB -IC -IC7

Saturation regionIn sat#ration region bot' t'e ?#n!tions E an( C are orar( biase( b* at least t'e !#tin $oltage& 'e $oltage VBE @VBC> a!ross orar( biase( emitter @!olle!tor> ?#n!tion 'as magnit#(e o

?#st a e tent's o a $olt& Nen!e t'e sat#ration region lies etremel* !lose to +ero $oltage ais& 'is ist'e region 'ere all !#r$es merge an( (e!line rapi(l* toar(s t'e origin& It ma* be obser$e( t'at t'esat#ration region begins at t'e JneeK o t'e !'ara!teristi! !#r$es&

3RCED7RE

+nput c-aracteristics5

1& MaQe t'e !onne!tions as per t'e !ir!#it (iagram&2& Ens#re t'e $oltage Qnobs o t'e poer s#pplies are in t'e minim#m position beore sit!'ing t'em

on&3& C'oose a $al#e or VCE& i t'e poer s#ppl* Qno VCCto get t'e (esire( $al#e o VCE&4& Var* t'e $oltage VBB in small steps& Ea!' time, note (on t'e $al#e o VBEan( t'e !orrespon(ing

$al#e o IB&%& C'oose anot'er $al#e or VCEan( repeat t'e abo$e steps&& ab#late all rea(ings an( plot IB$ers#s VBE&

utput C-aracteristics5

1& :se t'e same !ir!#it as abo$e or obtaining t'e o#tp#t !'ara!teristi!s&2& ;o maintain IB at some !onstant $al#e& Var* VCC an( obser$e t'e !'anges in IC (#e to t'e

!'anges in VCE&3& Initiall* Qeep IB7 \8& Var* VCCrom ero $olts an( note (on t'e rea(ings o IC" VCE&4& Repeat t'e abo$e pro!e(#re or a e ot'er $al#es o IBs#!' as 177 \8& ab#late all t'e rea(ings

as per t'e tab#lar orm&

0/"7$/R C$7MNS

+nput C-aracteristics Dra t'e s*mboli! representations o ;0; an( 0;0 transistors&3> Eplain p'*si!all* 'o amplii!ation is a!'ie$e( in a transistor& Is it $oltage amplii!ation or

!#rrent amplii!ationP )i$e an eample o a (e$i!e !apable o gi$ing an* ot'er t*pe@$oltage/!#rrent> o amplii!ation& G'at is t'e origin o t'e name HtransistorP

%4


55/93


4> )i$e t'e p'*si!al arrangements o a 0;0 ?#n!tion transistor an( (is!#ss 'o it pro$i(es !#rrentamplii!ation&

%> SQet!' t'e !'ara!teristi!s o a B in Common-Emitter Conig#ration& G'* is it !alle( Common-Emitter !onig#rationP

> or amplii!ation, '* is t'e CE mo(e o B preerre( o$er ot'er mo(es o operationP

> Is CE Conig#ration o B a !#rrent ampliier or a $oltage ampliierP Does an impe(an!etransormation also taQe pla!eP5> G'* (o e obser$e a p'ase-s'it o t'e o#tp#t it' respe!t to t'e inp#t in a !ommon emitter

stageP6> G'at is a Jloa(-lineKP G'at is its signii!an!eP Dierentiate beteen a&!& loa( line an( (&!& loa(

line&17> Eplain t'e o#tp#t !'ara!teristi!s o B in Common Emitter Conig#ration it' respe!t to (!

loa( line&11> G'at are '-parametersP G'at are t'e* #se( orP G'* are t'ese '-parameters preerre( o$er ot'er

parametersP12> Grite t'e t*pi!al $al#es o '-parameters at IE 1&3m8&

13> )rap'i!all* obtain t'e '-parameters or BC-17 B at IC %m8 an( VCE 2V&14> )i$e t'e $al#es o VCE Sat, VCE C#toan( VCE 8!ti$eor t'e transistor BC17&1%> G'at are t'e ot'er appli!ations o t'e !ommon emitter !onig#ration @ot'er t'an as an ampliier>P

%%


56/93


E23ER+MEN0 N >

1E0 CH/R/C0ER+S0+CS

/+M o obtain t'e stati! !'ara!teristi!s @(rain an( transer !'ara!teristi!s> o a #n!tion iel( Ee!transistor in t'e Common So#r!e Conig#ration&

/33/R/07S

S&;o& Item Range/Spe!ii!ation At*1 n-!'annel E BG17 12 DC 8mmeter 7-17 m8 13 DC Voltmeter 7-27 V 24 Resistor 4& QNal Gatt 1% D#al C'annel Reg#late( 0oer

S#ppl*7-37 V 1

3/R0 / DR/+N CH/R/C0ER+S0+CS R 70370 CH/R/C0ER+S0+CS

C+RC7+0 D+/6R/M

0HER

'e !ommon so#r!e (rain !'ara!teristi!s or a t*pi!al n-!'annel E are obtaine( b* plotting t'e(rain !#rrent against VDS@t'e (rain to so#r!e $oltage> it' V)S@t'e gate to so#r!e $oltage> as a parameter&'e gate orms a 0; ?#n!tion it' t'e !'annel& G'en a re$erse bias is applie( to t'is ?#n!tion, a spa!e-!'arge region is orme(& Sin!e t'e gate is relati$el* 'ea$il* (ope(, t'e spa!e-!'arge region eten(s moreinto t'e !'annel t'an into t'e gate& Nen!e t'e !'annel i(t' is re(#!e( as t'e re$erse bias $oltage V)Sin!reases& 'ereore, t'e $al#e o t'e (rain !#rrent (e!reases&

irstl* let #s !onsi(er t'e !on(ition or V)S 7V& ;o it' V)S7$ t'ere is no re$erse bias at t'e gate an('en!e t'e !'annel beteen t'e gate ?#n!tion is !ompletel* open& :n(er t'is !on(ition 'en VDS7V t'ereis no ele!tri! iel( applie( a!ross t'e (rain an( so#r!e& 'ereore ma?orit* !arriers @i&e& ele!trons in t'e!ase o an n-!'annel E> (o not !on(#!t an( t'e (rain !#rrent ID7 it' t'e appli!ation o a small$oltage VDSat (rain& 'e n-t*pe semi!on(#!tor be'a$es liQe a single resistor olloing 'ms la an((einite (rain !#rrent los& 'is (rain !#rrent ID$aries linearl* it' VDS& 'ereore, o'mi! $oltage (roptaQes pla!e a!ross t'e bar& 'is $oltage (rop @'i!' is non-#niorml* (istrib#te( it'in t'e lengt' o t'e

bar> re$erse biases t'e gate ?#n!tion res#lting in narroing o t'e !'annel& 'e (epletion region is not#niorml* (istrib#te(& It is more toar(s t'e (rain en( rat'er t'an at t'e so#r!e en(& 8s t'e magnit#(e o

%


57/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSRECt'e (rain $oltage VDSis in!rease( progressi$el*, a !riti!al $al#e o VDSis rea!'e( at 'i!' t'e !'annelgets almost !onstri!te( i&e&, more or less blo!Qe(& G'en VDS is #rt'er in!rease( t'e (rain !#rrent IDbe!omes !onstant& 'e $al#e o VDSor 'i!' t'e (rain !#rrent rea!'es almost a !onstant $al#e is !alle(t'e pin!' o $oltage Vp, 'e region o t'e !'ara!teristi! !#r$e or 'i!' VDSVpis !alle( t'e !onstant!#rrent region or t'e pin!'-o region& G'en a reg#lati$e $oltage is applie( at t'e gate, t'e re$erse bias att'e p-n ?#n!tion is greater an( pin!' o o!!#rs or smaller $al#es o VDS& 8lso t'e maim#m (rain!#rrent I(sis loer 'en !ompare( to t'e $al#e o t'e sat#ration (rain !#rrent I(ssat V)S7V&

3RCED7RE

DR8I; CN8R8CERISICS Conne!t t'e !ir!#it as per t'e !ir!#it (iagram&2> Initiall*, !'oose V)S7& MaQe V))7 so t'at V)Sbe!omes 7&3> Var* t'e (rain s#ppl* VDD starting rom 7V& ;ote t'e $oltage VDSan( t'e !orrespon(ing (rain

!#rrent I(&4> ab#late all rea(ings&%> Repeat steps 3 an( 4 b* taQing (ierent $ales o V)S@sa* V)S-1V, -3V et!>&

> 0lot I( $ers#s VDSin ea!' !ase&

R8;SER CN8R8CERISICS

1> Conne!t t'e !ir!#it as per t'e !ir!#it (iagram&2> C'oose a $al#e or VDS, sa*, 4V&3> Var* t'e (rain poer s#ppl* VDDto get VDas t'e !'osen $oltage& 'is is Qept #naltere( t'ro#g' t'e

rest o t'e steps&4> ;o, $ar* V)Srom 7V onar(s in small !on$enient steps& ;ote t'e !orrespon(ing $al#e o ID&%> bser$e t'at IDis maim#m 'en V)S7 an( IDbe!omes ero or some $al#e o V)S&> ab#late all rea(ings&

> C'ose anot'er $al#e o VDSan( repeat t'e abo$e pro!e(#re&5> 0lot ID$ers#s V)Sin ea!' !ase&

E4pected 6rap-

DR/+N CH/R/C0ER+S0+CS

%


58/93


0/"7$/R C$7MNS

DR8I; CN8R8CERISICS ID@m8> VDS@V> ID@m8>

%5


59/93


R8;SER CN8R8CERISICS ID @m8> V)S@V> ID@m8>

RES7$0

%6


60/93


61/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSRECE23ER+MEN0 N ?

"0 F "+/S+N6

/+M o (esign a sel-bias !ir!#it or a Bipolar #n!tion ransistor an( to $eri* its orQing&

/33/R/07S

S&;o& Item Range/Spe!ii!ation At*

1 ;pn transistor BC17 1

2 Resistors 4& Q, 3&2Q, 17" 1Q 1 ea!'

3 D&C& 8mmeter or m#ltimeter 7 to 27m8 1

4 D&C& Voltmeter or m#ltimeter 7 to 27V 1

% D#al C'annel Reg#late( poer s#ppl* 7-37V 1

0HER

Biasing is #se( to obtain a stable operating point against (e$i!e $ariation& 'e operating point(epen(s #pon transistor parameters an( t'e* in t#rn (epen( on temperat#re&'e transistor parameters liQe!'ange rom one transistor to anot'er, alt'o#g' t'e* are o similar t*pe& i&e& t'e $al#e o t'e parametersmig't be (ierent or (ierent (e$i!es belonging to t'e same t*pe.

E$en it' t'e state o t'e art in Semi!on(#!tor De$i!e e!'nolog*, transistors o a parti!#lar t*pe still!ome it' a i(e sprea( $ariation in t'e $al#es o some parameters&'ermal instabilit* !a#ses great!'anges in re$erse !#rrent IC7& It (o#bles or e$er* 17C rise in temperat#re& It in t#rn !a#ses t'e

!olle!tor ?#n!tion temperat#re to rise, 'i!' in t#rn in!reases t'e $al#e o IC7 #rt'er& 8s a res#lt, t'e$al#e o IC7in!reases an( t'ere o!!#rs a s'it in t'e A-point o t'e transistor&

'e Emitter biase( or t'e Sel-biase( !ir!#it orQs in t'e olloing manner& I t'ere is an in!reasein t'e !olle!tor !#rrent IC, t'en, t'e $oltage (rop a!ross t'e resistor Rein!reases& Be!a#se o t'is in!rease,t'e base !#rrent a!t#all* (e!reases& Be!a#se o t'is, t'e ee!t o t'e in!rease in t'e !olle!tor !#rrent is(e!rease(& Noe$er, t'ere is bo#n( to be loss o 8C signal gain (#e to t'e same reason&o a$oi( t'e losso 8C signal gain be!a#se o t'is, a !apa!itor is #se( to b*pass t'e emitter resistor Re&

1


62/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSRECC+RC7+0 D+/6R/M

3RCED7RE

1& Design t'e re#ire( !ir!#it as per t'e re#irements&2& 8ter !onne!ting t'e !ir!#it as per t'e (esign, meas#re VCE, VBE, Ve, IC, IB an( VC #sing

m#ltimeters& Cal!#late t'e stabilit* a!tor an( t'e operation point& Veri* t'eoreti!all*&

"SERV/0+NS /ND C/$C7$/0+NS

VCC

VC VE RC VB VCE IC

S 9

VCC ICRCF VCE 'i!' implies

IC @VCC- VCE>/RC

RB/RE @1F>@S-1>/ 1F9 S

V IBRBF VEF VBEG'ere V is t'e $oltage o t'e 'e$enins e#i$alent $oltage so#r!e&

V @IC/>RBF VEF VBE

2


63/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC'en,

R1 RB@VCC/V>

R2 R1V /@VCC-V>

rom t'e !ir!#it, t'e !#rrent t'ro#g' R1is gi$en b*

'ereore, t'e Voltage V2 (e$elope( a!ross R2is gi$en b* Voltage Di$ision^

V2VCCR2/@R1F R2>

B* appl*ing VL to t'e base !ir!#it

V2 VBE F VE VBE F IERE&

IE @V29 VBE> / RE&

;o, appl*ing VL to t'e !olle!tor si(e !ir!#it, e get

VCC ICRCF VCE F IE RE

IC@RCF RE> F VCE @sin!e IE IC>

VCE VCC - IC @RCF RE>

RES7$0

3


64/93


V+V/ VCE

1> G'i!' transistor parameters $ar* it' temperat#reP

2> G'at is meant b* Hloa( lineP3> G'at is meant b* t'e Joperating pointK o a transistorP

4> G'* is a !apa!itor #se( to s'#nt t'e emitter resistor o sel-biase( transistorP

%> G'at is meant b* t'ermal r#naa*P

> G'at are t'e ot'er biasing arrangements possible @ot'er t'an sel-bias>P

> G'* is t'e sel-bias !ir!#it preerre( o$er ot'er possible biasing !ir!#itsP

5> Deine Stabilit* a!tor an( eplain its signii!an!e&

6> G'at is t'e stabilit* a!tor o a Common-base transistor !ir!#itP

4


65/93


E23ER+MEN0 N @

1E0 "+/S+N6

/+M o (esign a so#r!e sel-bias !ir!#it an( $eri* its operation&

/33/R/07S

S&;o& Item Spe!ii!ation / range ;o& 1 n-E BG17 1

2 Resistors 4&Q, 22Q, 47 1

3 D&C& ammeter @7-177 ma> 1

4 D&C& $oltmeter @7-27 V> 1

% Conne!ting ires

0HER

8s in all ampliiers !onsi(eration m#st be gi$en to biasing t'e E to pla!e its operating point it'in t'elinear portion o its a!ti$e region& 'e a!tors go$erning sele!tion o operating point or a E aresimilar to t'at or B&:nliQe a B a re$erse bias $oltage is to be applie( a!ross t'e gate to so#r!e?#n!tion in a E& or a spe!iie( (rain !#rrent, t'e !orrespon(ing Vgs!an be obtaine(& Sin!e t'e gate!#rrent is negligible, t'e re#ire( so#r!e resistan!e !an be (etermine( as ratio o Vgsto I(&

8 !apa!itor Cs'a$ing $er* large $al#e is #se( to b*pass t'e resistor RSso as to a$oi( t'e (egenerati$eee(ba!Q or a&!& signals& 'e problem o biasing #rt'er is simpliie( b* t'e a!t t'at t'ere eists a $al#eVgsor 'i!' t'e (rain !#rrent (oes not !'ange it' temperat#re& Nen!e it is possible to bias a E orero (rain !#rrent (rit&

3RCED7RE

1> MaQe t'e !onne!tions as per t'e !ir!#it (iagram&

2> 8ppl* a $oltage o sa* 1%V to t'e !ir!#it&

3> Meas#re (rain !#rrent, V(s, Vgs&

4> Determine t'e operating point&

%> Design t'e $al#es o biasing resistors&

> Veri* t'e operation o !ir!#it&

%


66/93


C+RC7+0 D+/6R/M

RES7$0

V+V/ VCE

1> G'at is t'e a($antage o a E biasing !ir!#it abo$e B biasingP

2> G'at is t'e nee( or t'e !apa!itor CSP

3> G'* are t'e !o#pling !apa!itors re#ire(P

4> G'at is meant b* t'ermal stabiliationP

%> )i$e eamples o stabiliation !ir!#its


67/93


E23ER+MEN0 N );

CMMN EM+00ER "0 /M3$+1+ER

/+Mo (etermine t'e re#en!* response o a Common-Emitter B ampliier&

/33/R/07S

S&;o& ;ame Range/Spe!ii!ation At*1 ;0; B BC17 12 Resistors %2,1%,4&,177 NM 1 ea!'3 Capa!itors 7&71\,7&771\ 4 Reg#late( 0oer

S#ppl*7-37V 1

% Cat'o(e Ra*s!illos!ope

D#al ra!e @7-27 MN> 1

8 Signal)enerator 7-1777 QN 1

Conne!tingires/probes

0HER

In a single stage CE ampliier, t'e eaQ time-$ar*ing signal is applie( to t'e base o t'e transistor& D#e tot'is, a small base !#rrent @'i!' itsel is time $ar*ing> starts loing& D#e to t'e a!tion o t'e transistor, am#!' larger !#rrent los t'ro#g' t'e !olle!tor loa(& 'is !#rrent is a!t#all* abo#t ] times t'e base!#rrent& 'ereore, a eaQ signal applie( at t'e base appears in an ampliie( orm at t'e o#tp#t o t'etransistor !ir!#it& It is in t'is as'ion t'at t'e Common Emitter ampliier a!ts as an ampliier&

Noe$er, or t'e transistor to a!t as a goo( ampliier, t'ere are !ertain re#irements t'at m#st be met&0arti!#larl*, e nee( to st#(* t'e !ir!#itr* t'at is asso!iate( it' a pra!ti!al ampliier& 'e olloing aret'e $ario#s !ir!#it elements t'at are re#ire(&i> 'e biasing !ir!#it< 'e resistors R 1, R2an( Re orm t'e biasing !ir!#it or t'e transistor& 'isarrangement is ne!essar* to establis' a proper operating point& I t'e transistor is not properl* biase(, itma* go into sat#ration or t'e positi$e 'al !*!le or it ma* go into !#to in t'e negati$e 'al !*!le&

ii> Inp#t Capa!itor Cin< 8ll pra!ti!al signal so#r!es 'a$e some o#tp#t resistan!e& I ne!essar* stepsare not taQen, t'is resistan!e !omes in parallel it' R2o t'e biasing !ir!#it, (ist#rbing t'e operatingpoint& I a !apa!itor Cinis #se( in series it' t'e so#r!e as s'on, it allos onl* t'e a! !omponent to passt'ro#g' b#t isolates t'e signal so#r!e rom R2& )enerall*, an ele!trol*ti! !apa!itor or appropriate !apa!it*

is #se( as Cin&iii> Emitter B*pass Capa!itor Ce< 'e presen!e o t'e emitter resistor Rein t'e biasing !ir!#it 'as t'eee!t o re(#!ing t'e gain o t'e ampliier& 'is 'appens be!a#se t'e !#rrent loing t'ro#g' t'e Re!a#ses t'e emitter $oltage to rise& o impro$e t'e gain o t'e ampliier, t'e resistor Reis b*passe( b* a!apa!itor Ce& 'is !apa!itor pro$i(es a lo-impe(an!e pat' or t'e a! !omponent, t'ereb* impro$inggain&


68/93


i$> Co#pling Capa!itor C!< 'e !o#pling !apa!itor is !onne!te( beteen t'e o#tp#t o one stageto t'e inp#t o t'e se!on(& In its absen!e, t'e R!o t'e irst stage !omes in parallel to R1o t'e se!on(stage, (ist#rbing t'e operating point o t'e se!on( stage& 8lso, t'e !apa!itor ser$es to isolate t'e (!beteen t'e to stages&

6ain 'e ratio o t'e o#tp#t ele!tri!al #antit* to t'e inp#t o t'e ampliier is !alle( its gain& I t'e

o#tp#t an( t'e inp#t #antities are $oltages, t'e gain is !alle( t'e Voltage )ain o t'e ampliier&1reIuency Response 'e $oltage gain o an ampliier $aries it' signal re#en!*& 'is 'appensbe!a#se t'e rea!tan!e o t'e !apa!itors in t'e !ir!#it !'anges it' signal re#en!*& 8 plot beteen t'e$oltage gain an( t'e signal re#en!* o an ampliier is !alle( t'e re#en!* response o t'e ampliier&"andidt- 'e range o re#en!* o$er 'i!' t'e gain is e#al to or greater t'an abo#t 7&O @1/Y2times> o t'e maim#m gain, is Qnon as t'e ban(i(t' o t'e ampliier&Decibel 6ain 'e $oltage gain o an ampliier in (e!ibel notation is gi$en b* 27 log 17 8$'ere 8$is t'e$oltage gain&

(db "andidt- G'en t'e $oltage gain attains a $al#e o 1/Y2 times t'e maim#m gain, t'e De!ibel$oltage gain attains a $al#e t'at is 3(b less t'an t'e maim#m (e!ibel gain& 'ereore, t'e ban(i(t' o

an ampliier !an also be (eine( as t'e range o re#en!* o$er 'i!' t'e (e!ibel gain is not less t'an t'emaim#m (e!ibel gain min#s 3(B&

C+RC7+0 D+/6R/M

3RCED7RE

1> Conne!t t'e !ir!#it as per t'e !ir!#it (iagram& eep t'e signal generator in t'e sin#soi(al mo(e&2> C'oose a $al#e or t'e amplit#(e o t'e inp#t signal, sa*, %7 mV 0eaQ-to-0eaQ&3> 8ppl* a signal o re#en!* 27 N to t'e !ir!#it& bser$e t'e o#tp#t a$eorm on t'e CR& ;ote

t'e amplit#(e o t'e o#tp#t sin#soi(&

5


69/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC4> In!rement t'e re#en!* o t'e applie( signal in small !on$enient steps& Ea!' time, a(?#st t'e

inp#t amplit#(e to t'e !'osen $al#e @%7mV>& ;ote t'e o#tp#t amplit#(e& Repeat t'is step till are#en!* o 277 QN&

%> ab#late all rea(ings& 8t ea!' inp#t re#en!*, !al!#late t'e gain as 8$ Vo / Vi& 8lso in( t'e$al#e o t'e gain in (e!ibel as 27 log 8$&

> 0lot a grap' beteen t'e inp#t re#en!* @> an( t'e gain@in (e!ibel> on a semi-log grap' paper&> n t'e grap', i(enti* t'e 3(B points& 'e re#en!* range beteen t'e 3(B points is not'ing b#t

t'e ban(i(t' o t'e gi$en ampliier&

0/"7$/R C$7MN

Inp#t Voltage @Vin %7mV>

S&;o& Inp#tre#en!*

#tp#t Voltage@Vo#t>

Voltage )ain8$ Vo#t/Vin>

Voltage )ain in(b 27log@8$>

6


70/93


E23EC0ED 6R/3H

RES7$0

V+V/ VCE

1> G'at is t'e signii!an!e o t'e emitter-b*pass !apa!itor an( t'e !o#pling !apa!itor in t'e CEampliier !ir!#itP

2> Eplain '* re$ersal o p'ase o!!#rs in a B CE 8mpliier&

3> G'at is t'e signii!an!e o t'e operating point in t'e orQing o an ampliierP

4> G'at 'appens i an ampliier is biase( at !#to or at sat#rationP

%> G'at is a loa( lineP No is t'e a! loa( line (ierent rom t'e (! loa( lineP

> G'at is t'e signii!an!e o t'e ban(i(t' o an ampliierP

> G'at is meant b* )ain-Ban(i(t' 0ro(#!tP G'at is its signii!an!eP

7


71/93


E23ER+MEN0 N ))

CMMN S7RCE 1E0 /M3$+1+ER

). /+Mo st#(* an( obtain t'e re#en!* response o a !ommon-so#r!e E 8mpliier&

'. /33/R/07S

1


72/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSRECS&;o& ;ame Range/Spe!ii!ation At*1 n-!'annel E BG17 12 Resistors 6, %, 4&, 2&2 1 ea!'3 Capa!itors 7&71 \ 34 Reg#late( 0oer

S#ppl*

7-37V 1

% Cat'o(e Ra*

s!illos!ope

D#al ra!e @7-27 MN> 1

8 Signal )enerator 7-1777 QN 1 Conne!ting

ires/probes

(. 0HER

'e eaQ signal is applie( beteen t'e gate an( t'e so#r!e o t'e E& 'e o#tp#t is obtaine( beteen t'e

(rain an( t'e so#r!e terminals& or proper operation, t'e gate m#st be negati$e it' respe!t to t'e so#r!e, ie&, t'e

inp#t !ir!#it s'o#l( ala*s be re$erse biase(& 'is is a!'ie$e( b* t'e biasing arrangement&

8 small !'ange in t'e re$erse bias on t'e gate pro(#!es a large !'ange in (rain !#rrent& 'is a!t maQes

E!apable o raising t'e strengt' o a eaQ signal& D#ring t'e positi$e 'al o t'e signal, t'e re$erse bias on t'e

gate (e!reases& 'is in!reases t'e !'annel i(t' an( 'en!e t'e (rain !#rrent& D#ring t'e negati$e 'al-!*!le o t'e

signal, t'e re$erse $oltage on t'e gate in!reases& Conse#entl*, t'e (rain !#rrent (e!reases& 'e res#lt is t'e small

!'ange in $oltage at t'e gate pro(#!es a large !'ange in (rain !#rrent& 'ese large $ariations in (rain !#rrent

pro(#!e large o#tp#t a!ross t'e loa( RL& 'ereore, a E a!ts as an ampliier&

)ain< 'e ratio o t'e o#tp#t ele!tri!al #antit* to t'e inp#t o t'e ampliier is !alle( its gain& I t'e o#tp#t an(

t'e inp#t #antities are $oltages, t'e gain is !alle( t'e Voltage )ain o t'e ampliier&

re#en!* Response< 'e $oltage gain o an ampliier $aries it' signal re#en!*& 'is 'appens be!a#se t'e

rea!tan!e o t'e !apa!itors in t'e !ir!#it !'anges it' signal re#en!*& 8 plot beteen t'e $oltage gain an( t'e

signal re#en!* o an ampliier is !alle( t'e re#en!* response o t'e ampliier&

Ban(i(t'< 'e range o re#en!* o$er 'i!' t'e gain is e#al to or greater t'an abo#t 7&O @1/Y2 times> o

t'e maim#m gain, is Qnon as t'e ban(i(t' o t'e ampliier&

De!ibel )ain< 'e $oltage gain o an ampliier in (e!ibel notation is gi$en b* 27 log17 8$'ere 8$is t'e $oltage

gain&

3(b Ban(i(t'


73/93


8. C+RC7+0 D+/6R/M

=. 3RCED7RE

1> Conne!t t'e !ir!#it as per t'e !ir!#it (iagram& eep t'e signal generator in t'e sin#soi(al mo(e&2> C'oose a $al#e or t'e amplit#(e o t'e inp#t signal, sa*, %7 mV 0eaQ-to-0eaQ&3> 8ppl* a signal o re#en!* 27 N to t'e !ir!#it& bser$e t'e o#tp#t a$eorm on t'e CR& ;ote t'e

amplit#(e o t'e o#tp#t sin#soi(&4> In!rement t'e re#en!* o t'e applie( signal in small !on$enient steps& Ea!' time, a(?#st t'e inp#t

amplit#(e to t'e !'osen $al#e @%7mV>& ;ote t'e o#tp#t amplit#(e& Repeat t'is step till a re#en!* o1MN&

%> ab#late all rea(ings& 8t ea!' inp#t re#en!*, !al!#late t'e gain as 8$ Vo / Vi& 8lso in( t'e $al#e o t'egain in (e!ibel as 27 log 8$&

> 0lot a grap' beteen t'e inp#t re#en!* @> an( t'e gain@in (e!ibel> on a semi-log grap' paper&> n t'e grap', i(enti* t'e 3(B points& 'e re#en!* range beteen t'e 3(B points is not'ing b#t t'e

ban(i(t' o t'e gi$en ampliier&

. 0/"7$/R C$7MN

Inp#t $oltage %7m$re#en!* #tp#t Voltage

@Vo#t>Voltage )ain

@Vo#t/Vin>Voltage )ain

@(B>

3

6 Q

% Q

4& Q

2&2 Q


74/93


E23EC0ED 6R/3H

4


75/93


>. RES7$0

?. V+V/ VCE

)* Compare t-e operation and freIuency response of a Common Source 1E0 amplifier it- t-ose of a

Common Emitter "0 amplifier.

2> G'at are t'e a($antages o #sing a E instea( o a BP

3> G'at is t'e t*pi!al range o ban(i(t' or t'e E Common So#r!e ampliierP

4> G'* is a so#r!e b*pass !apa!itor #se( in a E Common So#r!e ampliierP

%> Can e inter!'ange t'e so#r!e an( (rain terminals in a E !ir!#itP Can e (o t'e same it' t'e emitteran( !olle!tor terminals o a B !ir!#itP

> G'at is a MSEP No is it (ierent rom a EP G'at are its t*pi!al appli!ationsP

E23ER+MEN0 N )'

EM+00ER 1$$ER

1& /+M o (etermine t'e re#en!* response, inp#t impe(an!e an( o#tp#t impe(an!e o a Common-Colle!tor B ampliier @Emitter olloer>&

'. /33/R/07S

%


76/93


77/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC8. C+RC7+0 D+/6R/M

=. 3RCED7RE

1> Conne!t t'e !ir!#it as per t'e !ir!#it (iagram& eep t'e signal generator in t'e sin#soi(al mo(e&2> C'oose a $al#e or t'e amplit#(e o t'e inp#t signal, sa*, %7 mV 0eaQ-to-0eaQ&3> 8ppl* a signal o re#en!* 27 N to t'e !ir!#it& bser$e t'e o#tp#t a$eorm on t'e CR& ;ote t'e

amplit#(e o t'e o#tp#t sin#soi(&

4> In!rement t'e re#en!* o t'e applie( signal in small !on$enient steps& Ea!' time, a(?#st t'e inp#t amplit#(eto t'e !'osen $al#e @%7mV>& ;ote t'e o#tp#t amplit#(e& Repeat t'is step till a re#en!* o 277 QN&%> ;oti!e t'at t'ere is no p'ase (ieren!e beteen t'e inp#t an( t'e o#tp#t signal o t'e 8mpliier&> ab#late all rea(ings& 8t ea!' inp#t re#en!*, !al!#late t'e gain as 8$ Vo / V i& 8lso in( t'e $al#e o t'e

gain in (e!ibel as 27 log 8$&> 0lot a grap' beteen t'e inp#t re#en!* @> an( t'e gain@in (e!ibel> on a semi-log grap' paper&5> n t'e grap', i(enti* t'e 3(B points& 'e re#en!* range beteen t'e 3(B points is not'ing b#t t'e

ban(i(t' o t'e gi$en ampliier&6> Cal!#lation o Inp#t impe(an!e< 1 resistor is present beteen Vs an( Vi& 'e !#rrent loing t'ro#g' t'is resistor is t'e !#rrent loing t'ro#g' t'e

netorQ& Ii @Vs-Vi> / 1 inp#t resistan!e Ri Vi/Ii&

17> 8mpliier& Cal!#lation o #tp#t impe(an!e< 8ppl* 1 N, %7mV signal at t'e inp#t no(e& Conne!t a DRBit' all sit!'es at min position& 8!ross t'e o#tp#t terminals an( in!rease t'e resistan!e s#!' t'at Vo Vi/2&

'e $al#e o resistan!e in t'e DRB is e#al to t'e o#tp#t resistan!e o t'e ampliier&

. 0/"7$/R C$7MN

Inp#t Voltage @Vin %7mV>


78/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSRECS&;o& Inp#t re#en!* #tp#t Voltage

@Vo#t>Voltage )ain8$ Vo#t/Vin>

Voltage )ain in(b 27log@8$>

>. E23EC0ED 6R/3H

?. RES7$0

5


79/93


V+V/ VCE

1> G'at is t'e signii!an!e o t'e !o#pling !apa!itor in t'e CC ampliier !ir!#itP

2> Eplain '* re$ersal o p'ase (oes not o!!#r in a B CC 8mpliier&

3> G'at is t'e signii!an!e o t'e operating point in t'e orQing o an ampliierP

4> G'at 'appens i an ampliier is biase( at !#to or at sat#rationP

%> G'at is a loa( lineP No is t'e a! loa( line (ierent rom t'e (! loa( lineP

> G'at is t'e signii!an!e o t'e ban(i(t' o an ampliierP

> G'at is meant b* )ain-Ban(i(t' 0ro(#!tP G'at is its signii!an!eP

5> G'* is t'e Common Colle!tor 8mpliier !alle( as Emitter olloerP

E23ER+MEN0 N )(

CH/R/C0ER+S0+CS 1 70 /ND SCR

/+M o obtain t'e a> $olt-ampere !'ara!teristi!s o :b> $olt-ampere !'ara!teristi!s o SCR

/33/R/07S

1& : eperimental trainer Qit it' #ser man#al an( 0at!' !'or(s&2& 7 - 1%V DC $oltmeter&3& 7 - 17m8 DC ammeter&4& Cat'o(e Ra* s!illos!ope

%a*Volt ampere c-aracteristics of 70

0HER

'e :ni #n!tion ransistor is a t'ree terminal semi!on(#!tor (e$i!e it' negati$e resistan!e!'ara!teristi!s& It !onsists o a bar o n-t*pe sili!on it' a small p-t*pe insert @emitter> near to one o t'een(s& 'e to o'mi! !onta!ts at t'e en(s o t'e n-t*pe bar !onstit#te to terminals Base-1 an( Base-2&'e re!ti*ing !onta!t is !alle( t'e Emitter& 'e (e$i!e s'os negati$e resistan!e !'ara!teristi!s beteenits Emitter an( Base -1 terminals&

6


80/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC8 ie( interbase potential VBB is applie( beteen Base-1 an( Base-2&'e most important !'ara!teristi! o : is t'at o t'e inp#t (io(e beteen E an( Base 1&I base-2 is open!ir!#ite(, t'en, IB27,inp#t V-I !'ar is same as t'at o t'e normal p-n ?#n!tion (io(e&or t'e ie( $al#e o VBB, a negati$e resistan!e !'ar is obtaine(&

'e prin!iple appli!ation o : is t'at o a sit!' 'i!' allos rapi( (is!'arge o a !apa!itor !onne!te(beteen emitter an( Base-1& t'is is t'e prin!iple o operation o a Relaation s!illator #sing :&

C+RC7+0 D+/6R/MS

3RCED7RE

1& Conne!t t'e !ir!#it (iagram as s'on in t'e ig#re&2& MaQe s#re t'at t'e potentiometer is in its minim#m position @anti !lo!Q ise (ire!tion> &&3& 8(?#st t'e potentiometer in !lo!Q ise (ire!tion an( note( (on t'e $al#es o t'e $oltmeter

an( milli ammeter&4& ab#late t'ese $al#es an( (ra grap' beteen emitter $oltage VEan( !#rrent IE&

0/"7$/R C$7MN

VBB V VBB5V

EmitterVoltage@V>

Emitter!#rrent@m8>

EmitterVoltage@V>

Emitter!#rrent@m8>

57


81/93


E23EC0ED 6R/3H

%b* V$0 /M3ERE CH/R/C0ER+S0+CS 1 SCR

). /33/R/07S

4& SCR eperimental trainer Qit it' #ser man#al an( 0at!' !'or(s&

51


82/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC%& 7 - 2%V DC $oltmeter&

& 7 - 177m8 DC ammeter&

& Digital m#ltimeter

'. 0HER

'e Sili!on Controlle( Re!tiier @SCR> is a semi !on(#!tor (e$i!e t'at is a member o a amil* o !ontrol (e$i!es!alle( t'e t'*ristors&

'e t'ree terminals 'a$e been name( as 8no(e@8>, Cat'o(e @> an( )ate @)>&

G'en )ate is open 'en SCR ires an( is in(i!ate( b* t'e loing o ano(e !#rrent& Voltage a!ross ano(e to !at'o(e alls&(> ;o, open t'e gate terminal an( obser$e 'et'er t'e SCR is ; or &e> I t'e SCR is in t'e ; state, t'en t'e ano(e !#rrent is eno#g' to Qeep t'e SCR in t'e ; position& I SCR

is , t'e in!rease t'e DC $oltage to some more $al#e an( repeat t'e abo$e pro!e(#re&> in( o#t t'e approimate $al#e o t'e 'ol(ing !#rrent&

)ate C'ara!teristi!s o SCR Conne!t t'e !ir!#it as s'on in t'e ig&b> Conne!t t'e ammeter an( t'e $oltmeter in t'e !ir!#it&!> 8(?#st t'e 8no(e to !at'o(e $oltage o SCR to its #ll $al#e&(> MaQe s#re t'at t'e )ate $oltage is in its min position& Voltmeter a!ross SCR #ll $oltage applie( an(

!#rrent meter s'os no rea(ing& 'is means t'at t'e SCR is in t'e state&e> ;o, $ar* t'e gate !#rrent o t'e SCR it' $oltage a(?#stment pot an( !#rrent a(?#stment pot #ntil t'e

SCR ires, 'i!' is in(i!ate( b* t'e alling o t'e $oltage a!ross SCR an( !#rrent loing t'ro#g' t'e

SCR&

=. 0/"7$/R C$7MN

Ig &%m8

V8@Volts> I8@m8>

53


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2V4VV

. E23EC0ED 6R/3H

54


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86/93


3H0 D+DE CH/R/C0ER+S0+CS

/+M a> Meas#re t'e Emitter C#rrent @IE> o t'e 0'oto Dio(e or (ierent lig'tintensities&

b> o (emonstrate sit!'ing ;- o an eternall* operate( 237V 8C (e$i!e @or eample atable an, 'air (rier et!>, 'en lig't intensit* e!ee(s be*on( a parti!#lar intensit*&

/33/R/07S&

0'oto (io(e trainer Qit, (igital m#ltimeter

0R/+NER J+0

0HER,&

G'en lig't is alloe( to all on a re$erse biase( p-n ?#n!tion (io(e a((itional 'ole-ele!tron pairs are!reate( in bot' p 9 an( n 9 regions& 'is pro(#!es a $er* small !'ange in ma?orit* !arrier!on!entration an( a $er* large !'ange in minorit* !arrier !on!entration& 'ese a((itional minorit*!arriers en'an!e t'e re$erse !#rrent sin!e t'e* all (on t'e barrier potential& It is o#n( t'at t'e!#rrent t'ro#g' t'e (io(e $aries almost linearl* it' t'e lig't l#& 'e (io(es (esigne( to operateon t'is prin!iple are !alle( p'oto (io(es& S#!' (io(es are #se( in lig't (ete!tion, intr#sion alarms, inlig't operate( sit!'es an( in rea(ing o !omp#ter p#n!'e( !ar(s et!&

3RCED7RE&

E4periment to measure Emitter Current K+EK

1& 0la!e t'e sit!' in IEposition

2& 0la!e a DMM at terminals inten(e( or meas#rement o C:RRE; in m8& MaQe s#re t'at t'e

terminals are pla!e( in proper so!Qets o DMM an( sit!'e( to DC C:RRE; position&

3& :se lig't intensit* !ontrol Qnob an( sit!' t'e lamp&

4& Meas#re emitter !#rrent IE &

%& :se lig't intensit* !ontrol Qnob an( meas#re emitter !#rrent or t'ree (ierent Qnob positions,

namel* LG, MID an( M8[ intensities&

& or no lig't in!i(en!e, t'e p'oto (io(e ill e'ibit lo !#rrent @a e _l8>& or 'ig' brig't

!on(ition t'e emitter !#rrent ill be more @a e tens o _>&

5


87/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSRECMaQe t'e obser$ation as ollos&

"SERV/0+N

Intensit* position IEin \8

; lig't

LG lig't

MID lig't

or M8[ lig't

;o (ra a grap' beteen Intensit* 0osition Vs Emitter C#rrent IE

b> o (emonstrate sit!'ing ;-// o an eternall* operate( 237V 8C (e$i!e 'en

lig't intensit* e!ee(s be*on( a parti!#lar intensit*` 'is is a simple eperiment& 'e aim o t'is

eperiment is to (emonstrate t'at a p'oto (io(e !an be #se( to (ete!t t'e presen!e or absen!e o lig't&

8s a res#lt o t'is a (e$i!e !an be operate(& 'ere is a 2-pin so!Qet in t'e rear si(e o t'is instr#ment&=o# !an pl#g a 237V 8C operate( !alling bell to t'is so!Qet& G'en t'e lig't impinging on t'e 0'oto

(io(e e!ee(s t'res'ol( point !on(#!tion taQes pla!e& 'ereore a rela* ill be sit!'e( ;& =ello

lamp ill be ; i t'e obstr#!tion beteen t'e 47Gatt lamp an( t'e trans(#!er is remo$e(& It ill be

// 'en t'e obstr#!tion is intro(#!e(& 0la!e t'e sit!' in to ampliier position &:se lig't

intensit* !ontrol Qnob an( sit!' t'e lamp&

Rotate lig't intensit* !ontrol Qnob #ntil lig't intensit* in!rease gra(#all*, till t'e rela* is sit!'e( ;&

G'en t'ere is no lig't alling on t'e trans(#!er, t'e =ello lamp is & I t'e lig't alls on t'etrans(#!er t'e =ello lamp ill be ;&

RES7$0

/ppendi4

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88/93


3H0 0R/NS+S0R CH/R/C0ER+S0+CS

/+M 1& Meas#re t'e Colle!tor C#rrent @IC> o t'e 0'otoransistor or (ierent lig't intensities&

2& Meas#re o#tp#t $oltage o t'e ampliier (e$elope( b* 0'otoransistor as a #n!tion o(ierent lig't intensities&

/33/R/07S& /or 'ig' brig't !on(ition t'e emitter !#rrent ill be more @a e '#n(re(s o _>&

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89/93

BE 2/4-I sem ED Lab, ECE Dept&, MVSREC"SERV/0+N

Intensit* 0osition Colle!tor C#rrent in \8

;o lig't !on(ition

LG Lig't

MED Lig't

/or Maim#m Lig't

;o (ra a )rap' beteen Intensit* 0osition Vs Colle!tor C#rrent&

b> E4periment to measure utput Voltage

1&0la!e t'e sit!' in ampliier position

2&0la!e a DMM at o#tp#t terminals inten(e( or meas#rement o $oltage

3&:se lig't intensit* !ontrol Qnob an( sit!' t'e lamp&

4&Meas#re t'e o#tp#t $oltage

%&:se lig't intensit* !ontrol Qnob an( meas#re o#tp#t $oltage or t'ree (ierent Qnob positions,namel* LG, MED an( NI)N intensities&

&or no lig't in!i(en!e, t'e 0'otoransistor ill e'ibit $er* lo $oltage or almost ero& or 'ig'brig't !on(ition t'e o#tp#t $oltage ill be maim#m, as per gain potentiometer settings& 'is illnot e!ee( more t'an %V DC&MaQe t'e obser$ation as ollos

Lig't intensit* #tp#t $oltage;o lig't !on(itionLo lig'tMe( lig'tMa lig't !on(ition

Dra a )rap' #tp#t Voltage Vs in!i(en!e lig't intensit* on t'e trans(#!er

RES7$0

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BE 2/4-I sem ED Lab, ECE Dept&, MVSREC/ppendi4

Measurement of -53arameters

/+M o (etermine t'e '90arameters o a bipolar ?#n!tion transistor in t'e !ommon emitter!onig#ration&

/33/R/07S

S& ;o& Item Range L Number At*&1 ;0; ransistor BC17B 1

2 D&C& 0oer S#ppl*@D#al C'annel>

7-37V 1

3 Resistors o'ms 4

4 M#ltimeters 3

% 0at!' !or(s / probes

0HER

Let V1,V2be t'e inp#t an( t'e o#tp#t $oltage o a to-port netorQ respe!ti$el*& Let I1an( I2bet'e inp#t an( t'e o#tp#t !#rrent respe!ti$el*& 'en, t'e o#r '-parameters are (eine( as ollos'22'o@pen-Cir!#it #tp#t Impe(an!e>

G'ile st#(*ing transistor !ir!#its, it is !ommonpla!e to #se a se!on( s#bs!ript it' t'is notation& 'ese!on( s#bs!ript generall* (enotes t'e t*pe o !onig#ration ie& Common emitter, !ommon base

et!&'ereore 'ib, 'rb, 'b, 'ob(enote t'e o#r '-parameters or t'e !ommon base !onig#ration& Similarl*,'ie, 're, 'e, 'oeare t'e '-parameters or t'e !ommon emitter !onig#ration&

'e e#i$alent !ir!#it o a !ommon-emitter transistor in terms o t'e '-parameters is as ollos 0lot t'e inp#t an( t'e o#tp#t !'ara!teristi!s o t'e gi$en transistor& ollo t'e re#ire( pro!e(#reto a!!omplis' t'e same&

2> 'en, rom t'e inp#t !'ara!teristi!s,Ge 'a$e'ieVbe / ib,V!ebeing !onstant'reVbe / V!e, Ibbeing !onstant

3> rom t'e o#tp#t !'ara!teristi!s, (etermine t'e olloing'eI!/ Ib , V!ebeing !onstant&'oeI!/ V!e, Ibbeing !onstant&

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BE 2/4-I sem ED Lab, ECE Dept&, MVSRECRES7$0

V+V/ VCE

1> G'* are '-parameters preerre( o$er ot'er parameters to anal*e B !ir!#itsP

2> G'* are '-parameters Qnon as '*bri(-parametersP

3> Eplain t'e approimate '*bri( mo(el o t'e B& No are t'e approimations (oneP

4> :n(er 'at !on(itions !an t'e approimate '*bri( mo(el o t'e transistor be #se(P

%> )i$e t'e !on$ersion orm#lae or !on$erting '-parameters in !ommon-emitter !onig#ration to t'ose

in !ommon-base an( !ommon-!olle!tor !onig#rations&

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ed lab manual manual

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